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Consciousness and Cognition 9, S64–S102 (2000) doi:10.1006/ccog.2000.0458, available online at http://www.idealibrary.com on

POSTERS ABSTRACTS Poster Session 1—June 30, 2000

P1-01. Covert Effects of Colour without Colour Consciousness. R. W. Kentridge, C. A. Heywood, & A. Cowey, Department of Psychology, University of Durham, Durham DH1 3LE, United Kingdom. E-mail: [email protected]. Experiments with normal subjects and with neurological patients suggest that we can use the wavelength of light entering our eyes to perceive form (segregate objects from their backgrounds on the basis of colour), to infer the wavelength of illuminant light and to infer the spectral reflectance properties of an objects surface (to see what colour it is). These functions are most obviously dissociated in cortical colourblindness or cerebral achromatopsia where some patients report that they have no subjective experience of colour, yet they successfully use wavelength alone to consciously perceive shapes defined by the border between objects and backgrounds of equal luminance. We now report a series of experiments in which we sought to identify whether surface colour had indirect effects on the perception of an achromatopsic. We used a variety of tasks in which we examined the interaction of colour and luminance and conclude that although surface colour is not consciously perceived it still interacts with the perception of luminance to produce a change in conscious percepts of an achromatopsic patient. P1-02. Temporal Dynamic of Early Visual Extrastriate Activity in a Blindsight Patient. Gilles Pourtois, Be´atrice de Gelder, Bruno Rossion, & Lawrence Weiskrantz, Tilburg University, Department of Psychology, Warandelaan 2, P.O. Box 90153, 5000 Le Tilburg, The Netherlands. E-mail: [email protected]. In previous event related brain potentials (ERPs) experiments, we have demonstrated early visual extrastriate activities (P1 component) elicited in response to visual presentations in the blind hemifield (right, RVF) of a well-known hemianopic patient (GY). This early visual positive deflection was delayed in time and reduced in amplitude compared to the P1 elicited in response to good visual hemifield presentations. In the present ERPs study, we tracked the temporal dynamic of this early visual extrastriate activity and assessed whether or not an early interhemispheric competition could be evidenced in GY despite his cortical blindness. GY was instructed to judge the orientation of faces presented either unilaterally or bilaterally. Results suggest an early interhemispheric competition since the presentation of a face in the RVF significantly decreased the amplitude of the P1 component generated in response to simultaneous presentation in the good visual hemifield. The existence of an alternative visual pathway and the possibility of an early interhemispheric transfer are proposed to account for our results. S64 1053-8100/ 00 $35.00

Copyright  2000 by Academic Press All rights of reproduction in any form reserved.

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P1-03. Controlled and Automatic Memory Processes in Alzheimer’s Disease. S. Adam, M. Van der Linden, & E. Salmon, Neuropsychology Unit, Faculte´ de Psychologie et des Sciences de l’Education, University of Lie`ge, Boulevard du Rectorat (B33) Sart-Tilman, 4000 Lie`ge, Belgium. E-mail: [email protected]. Recent studies suggest that cognitive deficits in early Alzheimer’s disease (AD) depend on a general impairment of controlled processes, while automatic processes are relatively preserved (Fabrigoule et al., 1998). This hypothesis was tested using the «process dissociation procedure» (Jacoby, 1991) that was designed to separate automatic and consciously controlled memory processes. Sixteen AD patients (MMS ⫽ 22 * 3.09) and 16 controls underwent the procedure. Subjects had to keep words (six letters) in memory. Subsequently, stems consisting of three letters were shown. In an inclusion condition, subjects had to complete each stem to recall a memorized word, or they had to complete stems with the first word that came to mind. Conversely, in an exclusion condition, subjects had to avoid completing stems with memorized words, but had to give another word. Interval between item encoding and stem presentation varied from 0 to 12 intermediate items. Measures of controlled and automatic processing were derived from subject’s scores. ANOVA showed that contribution of controlled processes in the memory task was significantly lower in AD patients than in controls. Moreover, the greater the interval between word encoding and stem completion, the greater the deficit in consciously controlled processes for AD patients. On the contrary, automatic processing did not differ between AD patients and controls. REFERENCES Fabrigoule, C., Rouch, I., Taberly, A., Letenneur, L., Commenges, D., Mazaux, J. M., Orgogozo, J. M., & Dartigues J. F. (1998). Cognitive process in preclinical phase of dementia. Brain, 121, 135–141. Jacoby, L. L. (1991). A process dissociation framework: Separating automatic from intentional uses of memory. Journal of Memory and Language, 30, 513–541.

P1-04. Assessing the Duration of Memory for Information Perceived without Awareness. Stephen D. Smith & Philip M. Merikle, Department of Psychology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada. E-mail: [email protected]. To assess memory for information perceived without awareness, participants were shown visual displays containing a cross in one quadrant and a word at the center. The displays were presented for 150 ms, and participants were instructed to first judge which arm of the cross was longer and then to attempt to read the word. Following each display, the participants indicated whether they saw an entire word (aware), or only part of a word or no word at all (unaware). Memory for the words (e.g., bench) was assessed by asking the participants to complete word stems (e.g., ben _ _) with words other than the words in the displays (i.e., exclusion instructions). Success in following these instructions was assumed to reflect conscious memory, whereas failure to follow these instructions was assumed to reflect unconscious mem-

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ory. When memory was tested either immediately following presentation or following delays averaging 32 min, participants failed to follow the exclusion instructions and used words that had appeared in the displays to complete the word stems. These findings indicate that words perceived without awareness not only influence performance immediately following presentation but also lead to durable unconscious memories that can influence performance for a considerable period of time. P1-05. The Time Course of Visual Awareness. V. Goffaux, S. Desmet, B. Rossion, & M. Crommelinck, PSP/EXPE/NECO, Place du Cardinal Mercier, 10, 1348 Louvainla-Neuve, Belgium. E-mail: [email protected]. Neuroimaging studies and electrophysiological recordings in monkeys have emphasized the contribution of infero-temporal cortex in visual awareness. Here we aimed at clarifying the temporal course of visual awareness in the normal human brain by means of event-related potentials (ERPs). Forty degraded stimuli depicting animals in natural scenes were learned (associated with their grayscale, meaningful version) during a training stage. Following training, we recorded ERPs during the presentation of learned and unlearned degraded images. Subjects were engaged in a visual recognition task. Comparison of the electrophysiological activity for the 2 sets of images leads to a higher N170 occipito-temporal potential during the presentation of meaningful (learned and recognized) stimuli. These preliminary results indicate that visual awareness in humans occurs quite early following visual presentation, at the level of occipito-temporal areas. As such, they are in line with neuroimaging studies and the time course of neurons’ responses as recorded in monkeys. They show that in humans visual awareness could occur earlier than previously thought from EEG studies. P1-06. Stronger Suboptimal Than Optimal Affective Priming. Mark Rotteveel & R. Hans Phaf, Department of Psychonomics, University of Amsterdam, Roetersstraat 15, 1018 WB Amsterdam, The Netherlands. E-mail: pn [email protected]. uva.nl. Behavioral consequences of less-conscious information processing are often diluted relative to the effects of fully conscious information processing. Studies with the affective priming paradigm (Murphy & Zajonc, 1993, JPSP, 64, 723–739), however, seem to provide a notable exception to this pattern of results. Affective evaluation of unfamiliar Chinese ideographs was only (congruently) influenced in the absence of conscious processing of the preceding affective stimuli. The affective priming results may thus form an argument in favor of the existence of nonconscious information processing. Attempts to replicate the Murphy & Zajonc (1993) findings have, however, not always been successful. It seems that variations in stimulus presentation (computer screen vs tachistoscope) are important. In comparison with tachistoscopic presentations brief presentation on a computer screen has the disadvantage of partial and ineffective stimulus presentation (see also Bridgeman, 1998, Psy. Sci., 9, 232– 233). Also the timing and nature of the response may play a role in the affective priming paradigm. With a fast and/or more direct dependent measure (e.g., facial EMG) a reliably stronger suboptimal than optimal affective priming was obtained.

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Our results support the notion that stronger less-conscious than conscious affective priming is a reliable phenomenon that reveals nonconscious affective processing. P1-07. How Do We Know There Is a Binding Problem? Fredrik Sundqvist, Dahlstrmsgatan 46, S-414 65 Go¨teborg, Sweden. E-mail: [email protected]. There seems do be an obvious answer to the question. We just have to notice one of the most characteristic feature of phenomenal experience consciousness as a unified field. This field consists of several subparts, but so closely knit together that they are more or less inseparable aspects of the whole. The binding problem arise in the study of neurophysiology. Intuition suggests that there needs to be a mechanism binding together the various, highly specialized, brain areas producing the unit of experience. The line of argument is a revival of an old and at the time highly celebrated hypothesis of the Gestalt psychologists: The hypothesis of psychophysical isomorphism. But exactly why should there be a binding problem? Is the absence of a binding mechanism a problem at all? And what should a discovery of such a unifying mechanism tell us about the relation between mind and matter? The purpose of this poster is twofold: First, to introduce the main features of the Gestalt psychologists discussion of the binding problem, the assumptions behind their perspective and some of the answers the Gestalt theory provide to the questions above., and second, to indicate a direction for further investigations of the binding problem. P1-08. Conscious Awareness versus Feeling of Familiarity: The Role of Perceptual Distinctiveness in Remember-Know (R/K) Procedure. Serge Nicolas, Chrystel Besche-Richard, & Nolwenn Quoniam, Universite´ de Bourgogne, LPCS, 36, rue Chabot-Charny, 21000 Dijon, France. E-mail: [email protected]. In this study, we proposed to evaluate the contribution of perceptual distinctiveness in subjective states of awareness (feeling of familiarity and conscious recollection), and more precisely to explore the picture superiority effect and the bizarreness effect in recognition memory task like Remember-Know (R/K) procedure (Gardiner & Java, 1993). In this recognition memory task, conscious awareness and feeling of familiarity were operationalized by respectively Remember and Know responses. In one encoding condition, the participants studied 10 words and 10 pictures. In a second condition, participants studied either 10 pictures of half normal drawings and half bizarre drawings or 15 normal drawings and 5 bizarre drawings. After each study phase, participants performed a R/K memory task. Results showed that proportion of Remember responses was higher than proportion of Know responses independently of study conditions. The more perceptual distinctiveness is increased at study the more proportion of Remember responses is elevated. This study emphasizes the role of encoding conditions and particularly the role of picture superiority effect and bizarreness effect in access of conscious recollection. Our results confirmed the perceptual distinctiveness effect in conditions which required exclusively an elaborative level of consciousness (explicit memory tasks, Remember responses).

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P1-09. Multistable Grouping in Discrete Periodic Patterns: A Psychophysical Study. Peter Claessens, Greet Kayaert, & Johan Wagemans, Laboratory for Experimental Psychology, Tiensestraat 102, 3000 Leuven, Belgium. E-mail: peter.claessens@ psy.kuleuven.ac.be. Multistable perception has been the classical playground of research involving dynamical percept formation. Following this tradition, Kubovy & Wagemans (1995) established a context for rigorous psychophysical analysis of multistable grouping by introducing experiments with dot lattices. The latter are two dimensional dot arrays, in which the elements are collinear in several orientations. The dots tend to be perceptually clustered to form lines. By manipulating the dot distances, the odds of organizing in one orientation versus a rivaling alternative were predicted by a descriptive model of proximity-based grouping. This research inspired numerous experiments related to interaction of proximity with other Gestalt principles. The set of stimuli was extended to include specific discrete periodic patterns (DPP, Gru¨nbaum & Shephard, 1989), thus opening the gate for integration of this exhaustive taxonomy of regular patterns in the psychophysical tradition. In one experiment, a dot lattice or one of several DPPs was presented for 300 or 600 ms in every trial. The participant indicated the percept by clicking the corresponding iconized version with the mouse. The results are characterized by interaction of several Gestalt laws. The outcome of this and other experiments will be summarized, and their implications for neural integration models will be discussed. P1-10. Unconscious Perception: Trade-Offs between Attention and Stimulus Quality. Haiyan Geng & Zhu Ying, Department of Psychology, Peking University, Beijing, 100871, People’s Republic of China. E-mail: [email protected]. The qualitative differences in performance were established across conscious perception and unconscious perception, based on two different phenomena: false recognition and exclusion failure. The experimental results showed that there were systematic trade-offs between attention and stimulus quality in determining whether a stimulus was perceived with or without awareness. That means, a poor quality stimulus, which was perceived without awareness, could be perceived with awareness either by increasing stimulus quality or by increasing attention; and correspondingly, a stimulus under divided-attention, which was perceived without awareness, could be perceived with awareness either by focusing attention or by increasing stimulus quality. Discussion focuses on the interrelations between awareness, attention and stimulus quality. P1-11. Implicit Sequence Learning in the Presence of Competing Explicit Cues: Hints on the Automaticity of Implicit Acquisition and Expression of Knowledge. Luis Jime´nez & Ca´stor Me´ndez, Facultad de Psicologı´a, Universidad de Santiago, 15706-Santiago, Spain. E-mail: [email protected]. In two experiments, the authors presented participants with a serial reaction-time task on the location of successive stimuli. These locations were structured to follow a probabilistic sequence generated through a finite-state grammar. The shape of each

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stimulus acted as an additional cue that allowed participants to predict next location with total accuracy. Half of the participants in each experiment were informed about the existence of predictive contingencies between shapes and locations. In Experiment 1 participants were also told to perform a secondary task that required them to focus on the shapes, and to keep a running count of the number of trials on which target shapes appeared. In Experiment 2 participants performed the serial reactiontime task alone. The results showed that implicit learning of the sequence imposed by the grammar was equivalent in both experiments, regardless of the secondary task and of the presence of competing cues. Participants in informed conditions reported on the explicit contingencies between shapes and locations, but only under single-task conditions could they follow them appropriately. These results indicate that implicit sequence learning is an automatic associative effect of attending to successive events and that, unlike explicit learning, it could be applied without any supplementary resources. P1-12. Unconscious and Conscious Processes in Semantic Priming. Sandrine Delord & Fre´de´ric Herbelleau, Laboratoire d’Etudes des Me´canismes Cognitifs, Universite´ Lumie`re Lyon 2, 5, av Pierre Mende`s France, 69 676 Bron cedex, France. E-mail: [email protected]. We tested whether the paradigm of masked priming can evidence a dissociation between access to semantic representations and visual awareness. In this situation, a mask that is presented before and/or after a short word prime, is supposed to selectively disrupt the processing of the prime before access to consciousness, without any perturbation of other processes, such as activation of prime stored representations. This is however difficult to reconcile with psychophysical models of visual masking. Prime duration was varied to manipulate prime visibility. Indirect priming of the target lexical decision and direct prime awareness (estimated by detection and identification of the prime) were both assessed at each trial. An inhibitory semantic priming effect (with longer lexical decisions for related targets than for non related targets) was found for the shorter prime durations. If a lenient criterion is used to assess awareness, these durations provided subliminal conditions of presentation, as prime detection was low, and as very few of the primes could be identified. When prime duration was increased, the prime identification improved to become perfect and priming reversed in a facilitator effect (with shorter RTs for related targets). These results are consistent with a high level attentional mechanism of masking. P1-13. From Localization to Patterns of Connectivity: Towards a Global Analysis of Brain Activity in Functional Neuroimaging Studies. Henrik Walter & Fritz Sommer, Department of Psychiatry, University of Ulm, Leimgrubenweg 12-14, 89075 Ulm, Germany. E-mail: [email protected]. In neuropsychology as well as in functional neuroimaging studies there is a natural tendency of localizing mental functions to certain brain regions. When studying basic cognitive phenomena like color or motion processing such an approach can be appropriate. However, it now seems to be the received view that a localizationist approach to consciousness is bound to fail. A neuroscientific theory of consciousness rather

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has to be of global nature, i.e., it must take into account global patterns of neural activity and their relational dynamics. The localizationist trend in functional neuroimaging studies is partly due to certain technical and methodological limitations. However, in recent years, new techniques such as event related fMRI have emerged and new methods of data analysis such as the analysis of functional and effective connectivity have been developed. These techniques and methods are more suitable to construct global theories of brain functions and thus eventually of consciousness. As an example I will present and discuss some of our own fMRI data on working memory, a cognitive function that always has been considered to be closely related to the phenomenon of consciousness. P1-14. Cortical Integration: How to Store Complex Representations in Long-Term Memory. Nick Bostrom, Department of Philosophy, Logic and Scientific Method, London School of Economics, Houghton Street, WC2A 2AE, London, United Kingdom. E-mail: [email protected]. This paper examines the efficiency and biological plausibility of various proposed solutions to the problem of cortical integration, including grandmother cells, cell assemblies, feed-forward structures, RAAM, and synchronization. It is argued that while some of these mechanisms may be involved in certain integration tasks, none of them can account for how complex representations are stored in long-term memory. A novel method, which I call binding through annexation, is proposed as a possible solution to this problem. Annexation enables simple representations to be combined in an efficient way into complex structured representations, which can be stored in long term memory using only Hebbian learning rules after a one-shot presentation of stimulus. Whether the brain actually uses annexation in this way is a question that could be settled by future experimental data. P1-15. Prior Learning Experience Influences Regional Cerebral Blood Flow during Human REM Sleep. Pierre Maquet, Philippe Peigneux, Steve Laureys, Martial Van der Linden, Carlyle Smyth, & Axel Cleeremans, Cyclotron Research Centre, Liege University, Bat. B30, Sart Tilman, B-4000, Liege, Belgium. E-mail: Philippe. [email protected]. The influence of waking experience on regional brain activity during sleep was estimated using H2150 with PET. Group A (7 subjects) was scanned during execution of a probabilistic serial reaction time (SRT) task. Group B (n ⫽ 6) was trained to the same SRT task, then scanned during the post training night (during waking and sleep stages). Group C (n ⫽ 5) was similarly scanned during night, but not trained to the task. A significant Group (B vs. C) by scan Condition (REM sleep vs. wakefulness) interaction discloses bilateral extrastriate regions, left premotor cortex and inferior thalamus, and mesencephalon more active in trained (B) than in non trained (C) subjects during REM sleep. To formally test that the reactivated areas are part of the brain regions that had been necessary for executing and learning the task, a conjunction analysis was performed that showed the regions that would be both more active during REM sleep in trained (B) than in non-trained (C) subjects and involved in the execution of the task at wake (A). Such significant reactivations were observed

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in bilateral extrastriate and left premotor cortices, and mesencephalon. These results lend support to the hypothesis of a processing of memory traces during REM sleep. P1-16. The Affective Simon Effect: How Automatic? How Conscious? Katia Duscherer & Daniel Holender, Universite´ Libre de Bruxelles, Laboratoire de Psychologie Expe´rimentale, CP. 191, 50, avenue F. D. Roosevelt, B-1050 Brussels, Belgium. E-mail: [email protected]. In Experiment 2 of J. De Houwer & P. Eelen (1998), participants responded by saying positive or negative depending on the grammatical category of a word having either a positive or a negative affective connotation. The authors argued that the resulting affective Simon effect is a useful tool for the study of automatic affective processing because they consider any variant which mirrors the formal relations between the stimulus and the response sets of the original spatial Simon paradigm as functionally equivalent to the latter. We dispute their logic and claim that while the spatial Simon effect can reflect both conditional and unconditional automaticity, the affective Simon effect can solely be based on conditional automaticity. Our results confirm this interpretation, indicating that the affective Simon effect can only be obtained in situations in which participants are aware of the relationship between the different elements of the experimental situation. P1-17. Clark and Sellars on Spatial Experience. Douglas B. Meehan, CUNY Graduate School, 125 Second Avenue #12, New York, New York 10003. E-mail: doug@ jebudas.com. In his forthcoming A Theory of Sentience Austen Clark explains spatial experience in terms of the neurological encoding of stimulated sensory receptors. He argues pace Paul Boghossian & David Velleman (1989) that we need not posit a two-dimensional spatial array to house visual phenomena, such as non-illusory afterimages. Clark also argues against Wilfrid Sellars’ more sophisticated theory (1956, 1959, 1960, 1967) which holds that sensory states have properties analogous to the spatial properties of distal sensory stimuli. I argue that Clark is wrong in dismissing Sellars’ theory of the mental counterparts of spatial properties. We need such mental properties to individuate the sensory states in virtue of which we become conscious of the spatial properties of our environment. Such individuation is needed to make the psychophysical identifications between sensory experiences and their neural correlates for which Clark argues. Further, I show that Clark’s theory is in fact committed to something like Sellars’ mental analog properties, and thus that the two theories are compatible in explaining the spatial character of visual experience. P1-18. Consciousness and the Brain: Do We Need a First-Person Neuroscience? Georg Northoff, Psychiatrische Klinik Universita¨t Magdeburg, Leipziger-Strasse 44, 39120 Magdeburg, Germany. E-mail: [email protected]. Introduction. There are various neuroscientific theories about consciousness. The purpose of the present account is to develop a methodological strategy, a so-called First-Person Neuroscience for neuroscientific investigation of consciousness. Meth-

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ods. In a first step the various neuroscientific theories of consciousness are reviewed by means of ‘‘analogisation’’ to arguments in the philosophical debate about qualia. In a second step the concept of a First-Person Neuroscience is described and defined which is further illustrated by examples from empirical studies. Results. The question for a theory of brain function, which considers the brain not only from the outside but in addition from the inside thus taking a systems/brain point of view as a FirstBrain Perspective. Since consciousness is necessarily tied to the First-Person Perspective it can be neuroscientifically investigated adequately only from the inside of the brain itself but not from the outside. In order to avoid an epistemic mismatch we need a First-Person Neuroscience. Conclusions. A novel methodological approach for neuroscientific investigation of consciousness is suggested—a First-Person Neuroscience which analyses, evaluates, and interprets neuroscientific data with regard to the phenomenal experiences in First-Person Perspectives. P1-19. Do the Results of Planning, Executive and Social Perception Tasks Show a Correspondence with Levels of Awareness of Deficit following Brain Injury? V. Voelzke, M. Breukel, W. Mandrella, L. Vichniak, S. Gilbertson, & W. Ischebeck, Klinik Holthausen, Clinic for Neurosurgical Rehabilitation, University Witten/Herdecke, Am Hagen 20, 45527 Hattingen, Germany. E-mail: voelzke.holthausen@ wka.de. This paper will present the results of our stepwise examination process of the awareness of deficit in patients following brain injury. These investigations are a continuation of the studies we presented in 1999. 61 patients were interviewed and neuropsychologically examined. Difficulties in perception were assessed in initially free, and later semi-structured interviews. In the following step, the patients were required to complete a self-assessment, using a given scoring system, before and after carrying out a set task. All lesion localisations were controlled by MRI. The results gained were correlated with those reported in other studies found in the literature. In this paper our attention is focused on the assessment of planning, executive functions (Tower of Hanoi) and social perception (Cartoons, Picture completion and Levine’s social perception task). Most patients presenting deficits in social perception tasks showed severe over-estimation. Some significant correlation between reduced levels of awareness and conspicuous planning and executive tasks was found. The implications of the results will be discussed. P1-20. Schematising Art: Art and the Nature of Experience. Annamaria Carusi, Department of Philosophy, University of Cape Town, c/o P.O. Box 1344, Highlands North, Johannesburg 2037, South Africa. E-mail: [email protected]. From the subjective point of view, perceptual experience appears to be organised, seamless and unified. Moreover, these aspects of experience appear to be simply given, since, in normal circumstances, the phenomenology of perceptual experience hides the fact that its ordered nature results from various types of processing. The fact of processing of various types is backed up by philosophical, neurological and cognitive scientific evidence. However, for each of these accounts there is potentially a gap between the phenomenology of experience and the processes posited, since at

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least some of the processes involved are not evident within them or are not phenomenologically salient. I propose that there is a type of experience most commonly had in interactions with art which makes available to experience some of the processes involved in producing it that are normally below the threshold of phenomenological salience. In particular, these are the pre-conscious temporal, structural and imagegenerating schemata, currently regarded as biological and as mental or cognitive organising structures. The paper explores the significance of this account of aesthetic experience for our understanding of experiential processes, by contrasting it with (a) accounts which focus on lesion or abnormality in order to draw conclusions about the normal functioning of the brain and cognition, (b) recent neuro-biological and cognitive studies which focus on typical features of art. P1-21. Can We Find Emotions in Functional Imaging? Alexander Heinzel, Psychiatrische Klinik Universita¨t Magdeburg, Leipziger-Strasse 44, 39120 Magdeburg, Germany. E-mail: [email protected]. Most philosophical concepts of emotions distinguish in general two main characteristics: Intentionality and feeling. Intentionality describes the cognitive and the motivational dimension. Feeling means the subjective way in which we experience certain emotions, which is philosophically discussed as the qualia-problem. The recent development of functional imaging techniques strongly enlarged the possibilities of empirical neuroscience, which tries to localise the neural correlates of emotions. Comparing philosophical characteristics of emotions with their neuroscientific investigation the following questions are posed: 1. Do the neuroscientists succeed in explaining plausibly the intentional dimension? 2. Are they able to grasp also the feeling dimension? In a theoretical analysis some studies on emotion with functional imaging are reviewed with respect to the properties of emotions pointed out in philosophy. It results that there is a certain plausibility to consider the intentional properties of emotions as represented in functional imaging. In contrast the neural representation of the feelings leads to some problems. It will be suggested that these problems in empirical investigation of feeling may be related to the special characteristics of qualia. P1-22. Conceptual Short-Term Memory, Meaning Integration, and Conscious Experience. Henk J. Haarmann & Eddy J. Davelaar, 0100 Lefrak, Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742. E-mail: [email protected]. We investigated the effect of individual differences in conceptual Short-term Memory capacity on the active maintenance of word meaning during on-line sentence comprehension. Participants were grouped into high and low conceptual span subjects based on their performance on a semantically cued recall task. They read filler-gap sentences in which a phrase (filler) was separated by intervening words from a subsequent phrase (gap) with which it was integrated. In non-filler-gap, control sentences, the filler was absent, reducing the memory load. The nouns inside the filler-gap interval were either semantically related or unrelated. Filler effects, that is, slower word read times for filler than non-filler sentences, were obtained for all participants at

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the gap, regardless of semantic relatedness. High but not low conceptual span subjects showed filler effects during the filler-gap interval (at its end only in related condition) and after the gap. Comprehension accuracy was better for high than low conceptual span subjects. The results suggest that the capacity of conceptual Short-term Memory determines a person’s ability to actively maintain word meanings in the focus of awareness, thus affecting the unity of conscious experience of the various concepts expressed in a sentence during their moment-to-moment on-line processing. P1-23. Chalmers’s Metaphysics of Consciousness: A Logico-Philosophical Inquiry. Marc Dominicy, Linguistics Department, Universite´ Libre de Bruxelles, CP 175 Avenue Roosevelt, 50, B-1050 Bruxelles, Belgium. E-mail: [email protected]. Chalmers’s definitions of local or global (logical) supervenience are formulated in a mixture of ordinary English and naive set-theoretical language. This makes it difficult to capture the real quantificational structures of statements concerning (non-) supervenience. I will propose quantified versions of those definitions which will enable me to argue: (i) that statements about (non-)supervenience cannot be logical truths (in that it is reasonable to assume that they are not semantically persistent, i.e., preserved in any informal use of a semantic metalanguage); (ii) that they cannot be laws because, under reasonable assumptions (e.g., that the number of possible individuals is infinite), they are unfalsifiable; (iii) and thus that they are metaphysical statements. The question then arises whether they are positive or negative metaphysical statements. I will argue that statements of non-supervenience are positive, while statements of supervenience are negative. Relying on this result, I will derive the claim that the property of being such that consciousness does not supervene on physical properties supervenes on physical properties. This means that if consciousness does not supervene on the physical, there is at least one positive fact about consciousness which follows from the physical. Thus, if Chalmers is right, no absolute form of naturalistic dualism can be maintained. P1-24. Fusing Significance Coding with the Stream of Cognitive and Conscious Sequences: Generalizing from a Neurocomputational Model of Motivated Saccadic Eye Movements. Marica Bernstein & John Bickle, Focused Research Program in Computational Neuroscience, Brody 6N51, East Carolina University, Greenville, North Carolina 27858-4353. E-mail: [email protected]. Many cognitive and conscious processes whose output is sequential share certain temporal and contextual features: later events in the sequence relate to and depend upon earlier events, and multiple steps are computed in advance and executed semiballistically without time for reflective feedback. In a previous neurocomputational model we used a vector space interpretation of cognitive/conscious representation and neural activity to hypothesize a biologically plausible mechanism for sequential processes with these and other features (Bickle et al., in press). However, in that model we provided no neurobiological account for an additional feature of many sequential processes: internal motivations can contribute to determining the sequence of cognitive/conscious outputs irrespective of the surface properties of individual points in the sequence. We expanded the model to include the effect of affect (Bern-

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stein et al., in press; Bernstein et al., 1999), and hypothesized a mechanism that interrupts a sequence and returns the system to a previous point based on its motivational significance. Our model provides a neurocomputational mechanism for the fusing of affect with sequential processing and given its biological plausibility, points toward a neurophysiological explanation for this integration. It also yields initially surprising but ultimately defensible implications about the phenomenology of motivated conscious streams. P1-25. Ontogeny of the Narrative Self and Unity of Consciousness. Tillman Vierkant, Bianca Jovanovic, Sabine Maasen, & Wolfgang Prinz, Max Planck Institute for Psychological Research, Amalienstrasse 33, 80799 Muenchen, Germany. E-mail: [email protected]. Ian Hacking coined the term false consciousness. It is supposed to denote a mental state, that depicts reality about ones own past wrongly in an essential sense to ones own life story. Hacking thereby links consciousness and ‘the self ’. This paper does agree with the gist of this argument, but feels that it is necessary to discern the concept of self that Hacking uses. Ontogenetical arguments are put forward to distinguish narrative and minimal self (distinction as introduced by, e.g., Gallagher). Only the former is found to be directly connected to consciousness, whereas the later is not. However, the connection between the two types of selves is intricate. In early human ontogeny the narrative self comes into existence in a cognitive system that already comprises a very subtle and complex minimal self. The transition between the two self types is shown to be marked by the development of an early representational self which forms the basis for further conceptual elaborations. This early prenarrative self serves as a focus for describing the difficulties in distinguishing the two self types. Bearing this intricacy in mind, the paper concludes with an examination of Hackings moral claim about the unity of consciousness and self. P1-26. From Feature Integration to Unified Experience: Proposed Directions for Research on the Binding Problem. Diana S. DeStefano, Institute of Interdisciplinary Studies, Carleton University, 2216 Dunton Tower; 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada. E-mail: [email protected]. Research on the binding problem can profit from an integration of the approaches taken by multiple disciplines, as the integrated whole of the approaches will be greater than the sum of the parts. This paper makes the following four arguments regarding reformulation of the research agenda: (1) An analysis of common assumptions suggests that research efforts should be focussed on investigation of top-down influences on perception and the search for macrolevels of neural organization. (2) The study of nonlinear dynamic patterns of activation in the brain is vital to binding problem research. (3) We should concentrate efforts on understanding how visual feature integration is accomplished by birds, or other animals whose visual system is less similar to the human system than those of cats and monkeys. The internal dynamics of the mammalian system are sufficiently complex to mask patterns that may more easily be detected in simpler systems. (4) Assume that the binding problem in language will have a very different sort of solution than those in the domain of object percep-

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tion. Once the mechanisms are better understood in the separate domains, we may look for unifying principles, but suggestions of a general solution to the binding problem are premature. P1-27. Intentional Binding of Spatial Consciousness in Individuals and Groups. J. Scott Jordan, Department of Psychology, Saint Xavier University, 3700 W. 103rd Street, Chicago, Illinois 60655. E-mail: [email protected]. Historically, the concept intentionality referred to the apparent directness of human consciousness. Given experimental psychology’s turn-of-the-century shift from consciousness to behavior, however, intentionality is now most often regarded as a prespecification of motor output. As a function of this gradual re-defining, it is behavior that is seen as being directed, while spatial consciousness is most-often vaguely conceptualized as a phenomenal reaction to behavior-environment transformations. The purpose of the present paper is to present research which empirically demonstrates the following points: (1) spatial consciousness is anticipatory in nature, as well as reactionary, (2) this anticipatory phenomenal context derives from the body-environment relationships (i.e., intentions) being attained/maintained from moment to moment, (3) such intentions bind the contents of spatial consciousness, in that they provide an anticipatory phenomenal context within which newly-arriving environmental information attains its spatial meaning, and (4) they (i.e., intentions) dictate that members of a group who share, and are working toward, a common spatial goal, must allow their own individual intentions to become bound within a group-in-theenvironment anticipatory context (i.e., intention) that entails agreed-upon spatial anchors (i.e., locations in the environment) around which individual actions can be effectively organized (i.e., the individual actions do not interfere with one another). P1-28. A Slow-Motion Video Analysis of the Arrival and Circulation of Initially Unbinded Input within Consciousness. Derek J. Smith, School of Health and Social Sciences, University of Wales Institute, Cardiff, Llandaff Campus D208, Western Avenue, Cardiff CF5 2YB, United Kingdom. E-mail: [email protected]. Although the science of artificial intelligence is still many years away from being able to provide hard copy minds upon which destructive research might be directly conducted, recent advances in design and animation software have already provided an impressive set of simulation and animation tools. However, attempts to apply these tools to information flow diagrams of biological cognition are actually quite rare. This moving poster presents the results of a computer animation exercise conducted for teaching purposes at University of Wales Institute, Cardiff. Using Smith’s (1999) diagram, it animates the flow of information around the modular layout of the adult human cognitive system. It does this during a particularly delicate moment of focussed consciousness, namely that of deciding upon approach to a vaguely familiar person whether to greet same warmly or formally. A 10-second animated action sequence is presented interchangeably at natural speed and single frame advance with commentary. This 10-second clip contains 300 discrete cine frames, each of which

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would require a full page diagram and rich annotation if presented in conventional form. Speculative attention is drawn to points within the information flow where phenomena akin to binding might well be concentrated. P1-29. Mapping the Mind: On the Status of Functional Explanation in the Cognitive Sciences. Rimas Cuplinskas & Hans-Christian Schmitz, Institut fuer Kommunikationsforschung und Phonetik, Universitaet Bonn, Poppelsdorfer Allee 47, D-53115 Bonn, Germany. E-mail: [email protected]. Advancements in the cognitive sciences (such as in simulation techniques) as well as in neurosciences (especially in imaging techniques) have in recent years encouraged strong claims to be made concerning the explanation of cognitive abilities or the identification of their neural correlates. The aim of this presentation will be to analyse more carefully the status of the concept of explanation involved from the viewpoint of philosophy of science, and to define more clearly the relation between theories of different disciplines concerning the same phenomena. According to our view, the common approach different disciplines take towards explaining cognitive phenomena involves positing an underlying functional architecture implemented by the system. Empirical data is employed to confirm or falsify hypotheses concerning the functional architecture involved. The difference between low-level neurosciences and high-level cognitive sciences is a difference concerning the level of abstraction of the functional model in question. From this view, the question of intertheoretical reduction can be seen as a question of reducing a more abstract functional architecture to a less abstract one. The presentation will involve a discussion of different meanings of reduction and their relation to positions in contemporary philosophy of mind. The reduction of linguistics to neurolinguistics will be discussed as an example. P1-30. The Influence of Goal-Directed Movements on Ideomotor Action. Sara De Maeght, Lothar Knuf, & Wolfgang Prinz, Max Planck Institute for Psychological Research, Cognition and Action, Amalienstrasse 33, D-80799 Munich, Germany. Email: [email protected]. Ideomotor phenomena are involuntary movements induced by the contents of perception, i.e., observing the activity of another person or a physical object. For example, when bowling people often move their bodies as if they could steer the thrown bowling ball in their desired direction. Although they know they have no influence in the scene, people still make movements as if they had. We are interested whether these movements are induced by observed situations or by intentions of the subjects or both. In particular, we want to test if these goal-directed movements have to be executed before they will show up in ideomotor movements. We conducted three billiards-like experiments. In Experiment 1, subjects executed a goal-directed action. In Experiment 2, subjects practiced a goal-directed action with a reversed movementeffect coupling and in Experiment 3, subjects did not perform this action. Afterwards all the subjects were tested for ideomotor behavior. In all experiments indications for ideomotor actions were found. In Experiments 1 and 2, these movements showed

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up in the whole body and in Experiment 3, only in the task-relevant effector. We can conclude that execution of goal-directed actions is not necessary for ideomotor movements but does enlarge its magnitude. P1-31. Ivar Segelberg on the Vertical and Horizontal Unity of Consciousness. Christer Svennerlind, Department of Philosophy, Go¨teborg University, Box 200, SE-405 30 Go¨teborg, Sweden. E-mail: [email protected]. The paper presents and discusses a theory worked out by the Swedish philosopher Ivar Segelberg, professor in theoretical philosophy 1951–1979, Go¨teborg University. It concerns the vertical and horizontal unity of consciousness. It is presented in ‘Studies of Consciousness and the Idea of the Self ’. The concepts constituting the foundation of the theory are also worked out in two other works of Segelberg, ‘‘Zeno’s Paradoxes’’ and ‘‘Properties.’’ These three works have recently become accessible in English; translations performed by Herbert Hochberg and Susanne Ringstro¨m Hochberg, and published in Library of Theoria No. 25, Thales, Stockholm (1999). Segelberg’s theory—as well as his philosophy in general—is ontological in outlook. It shows affinities with the philosophies of E. Husserl (intentionality), C. D. Broad (unity of consciousness) and G. F. Stout (ontology of tropes). Concepts formed in terms of basic categories—such as quality-trope, intentional and non-intentional relation, complex unity—are used to build a general theory of consciousness. A particular application of the general theory concerns the different ways in which consciousness can be said to be unitary. P1-32. From a Double Aspect Theory of Information to Human Consciousness. Liane Gabora, Center Leo Apostel, Vrije Universiteit Brussel, Krijgskundestraat 33, 1160 Brussels, Belgium. E-mail: [email protected]. Chalmers, double aspect theory of information proposes that information has a conscious aspect. The obvious question then is how do you get from phenomenal information to the real McCoy, human consciousness? That is, what sort of architecture could coerce bits of phenomenally-endowed information to integrate their individual subjectivities into a single, concentrated subjectivity? Biological systems are a perfect candidate in virtue of the fact that they are autopoietic, and autocatalytically closed. The direction of information processing in such a system is nonsymetrically inward-biased; thus information is locally amplified and integrated. Moreover, they generate not just novel information-processing components, but exactly those whose information-providing potential can be exploited by what is already in place, thereby enabling the system to function as a unified whole. This effect may be magnified through a second level of autocatalytic closure in the human mind, where memories and concepts are woven into an interconnected conceptual web. This not only amplifies our own consciousness, but tends to make us underestimate the degree to which non-self entities are conscious, where self is viewed in an extended sense; i.e., we tend to empathize with (experience what it feels to be) entities that are genetically (or memetically) similar to us.

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P1-33. The Limitations of Measures of Dissociation. Angela Pearce, University of Western Sydney–Macarthur, Post Office Box 555, Campbelltown, New South Wales 2560 Australia. E-mail: [email protected]. The construct of dissociation is central to many areas of psychotherapy. However, recent work by Hacking (1995) and others suggests the construct is ill defined and attempts to measure it have floundered on poor construct validity. This study reports a study of differences in dissociative states in high demand religious groups which echoes concerns about the current conceptions and measurement of dissociation. Findings from this research were, on analysis, as much an artifact of the limitations of current measures of dissociation, as an experimental finding worthy of further examination. Problems with current conceptions and measurement of dissociative states are discussed. These include the underlying assumptions of self unity and consciousness. P1-34. The Attribution of Artificial Consciousness. Christian Kaernbach, Institut fu¨r Allgemeine Psychologie, Universita¨t Leipzig, Seeburgstrasse 14-20, D-04103 Leipzig, Germany. E-mail: [email protected]. The strong AI position asserts that artifacts can have real, conscious minds. The question, however, whether an artifact is conscious or not can not be answered empirically. The present contribution suggests to study the attitude of man towards intelligently behaving artifacts. The behavior of man indicates clearly whether he/she attributes mind to something. An indirect strong AI position would be to assume that artifacts can be created that will be considered as conscious. The present contribution discusses which factors could be considered as crucial for the attribution of consciousness to artifacts. P1-35. Perceptual Principles, Aesthetic Form, and Notions of Unity. Jennifer McMahon, Building 5, Division of Communication and Education, University of Canberra, ACT 2601, Australia. E-mail: [email protected]. There are a number of problems associated with the classic notion of beauty understood as an experience of perceptual form. These problems are that there is an apparent incompatibility between beauty’s objectivity and subjectivity; and an incompatibility between the two self-evident theses that (i) there are no principles of beauty and (ii) there are genuine judgements of beauty. There is also the problem of explaining the possibility of a disinterested pleasure. To solve these problems I draw upon the work of Glyn Humphreys & Dietmar Heinke (1998) according to whom the processing of ‘between-object’ relations draws upon view-dependent primitives and the processing of ‘within-object’ relations draws upon view-invariant primitives. I argue that if what we experience as aesthetic form or beauty is some kind of play on the processes involved in processing within-object-relations during the course of perceiving certain objects, then the apparent problems of beauty would be resolved. I speculate that perhaps the perception of certain objects employs perceptual principles in an unprecedented way or in a way which epitomizes their normal operation. The idea is that when perception is employed in such a way that our attention is

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drawn from the object recognized to the experience of perception as something like a solution to a problem (that is, to the experience of the construction of within-objectrelations), then we experience what we know of as aesthetic form and beauty. P1-36. What Happens When Metacognition Fails? Some Implications for Children with Attention Deficit Hyperactivity Disorder (ADHD). He´le`ne Poissant, Valentin MBe´kou, & Christiane Chalfoun, De´partement des Sciences de l’E´ducation, UQAM, C.P. 8888, Succ. Centre-ville, Montre´al, P.Q., H3C 3P8, Canada. E-mail: poissant. [email protected]. According to different theoreticians, metacognition relates to the consciousness that individuals, adults or children, have about their own thinking processes and to the ability to have control of those processes (Vygotsky, 1934/1962). Several theorists (e.g., Pinard, 1989) concur that metacognition corresponds to a take over by individuals of their own cognitive functioning. As a component of the metacognitive system, self-regulation relates to experience, feelings, and thoughts that occur during an ongoing cognitive activity (Flavell, 1979). Those experiences give individuals an internal feedback (see Barkley’s 1998 internalized language notion) about the efficiency of their mental monitoring (How should I proceed?, I think I am proceeding well, I must try to avoid this error, etc.). Self-regulation can intervene in a cognitive activity without the person’s awareness. Under normal conditions and to some degree, we possess some unconscious knowledge or automatisms that enable us to structure and organize our behavior. However, it seems that adults, and to a lesser extent children, are able to consciously use rules and strategies to solve a problem. This cognitive awareness appears to be fully reached only toward adolescence and insures the adult with a continuous intellectual growth. However, in some circumstances, that we will explore, this metacognitive functioning does not work in the expected way. P1-37. Temporal Sequences Patterns Learning and Dynamic System Control (DSC). Mario Pandin, Giuseppe Didone’, & Silvio Bicciato, Via Marconi 67, 35014 Fontaniva (PD), Italy. E-mail: [email protected]. We have investigated the role of temporal sequence learning, using an unsupervised artificial neural network (1), called Monoconnected Autoreflexive Neural Network, for better understanding the implicit learning process role, involved during elementary associative learning processes. Several neural network models have been proposed to describe implicit learning (IL), using unsupervised and self-organized models (2, 3). In our experiments we used a real biochemical data set consisting of 15 features, that deals with penicillin production (112 temporal sequence blocks with 11 sequence points per block (1232 patterns). The prediction task requires that the neural network can predict the correct sequence position, after a preliminary training (50% of all patterns). After training, the neural network learn to find the correct position in the temporal sequences with good accuracy. Our results seem to confirm that elementary associative learning, could be used in temporal sequence learning and that dynamic system control (DSC) tasks (for instance to know which features are more sensitive to a better penicillin production), could be derived from the im-

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plicit learning process, using the importance of different features, recovered from the weight matrix analysis. REFERENCES 1. Pandin, M., & Didone’ G., (1996). Chaos in information processing: simulation of a biological learning process by time evolution in a unsupervised neural network. International Journal of Bifurcation and Chaos, 6, 203–210. 2. Dominey, Peter Ford (1998). A shared system for learning serial and temporal structure os sensorimotor sequences? Evidence from simulation and human experiments. Cognition and Brain Research, 6, 163–172. 3. Boyer, M., Destrebecqz, A., & Cleeremans, A. (1998). The Serial Reaction Time Task: Learning without Knowing, or Knowing without Learning—Proceedings of the Twentieth Annual Meeting of the Cognitive Science Society, pp. 167–172. NJ-Erlbaum.

P1-38. Attention through Self-Synchronisation in the Spiking Neuron Stochastic Diffusion Network. K. De Meyer, J. M. Bishop, & S. J. Nasuto, Department of Cybernetics, University of Reading, Whiteknights, Reading, Berkshire, RG6 6AH, United Kingdom. E-mail: [email protected]. The paper discusses ensemble behaviour in the Spiking Neuron Stochastic Diffusion Network, SNSDN, a novel network exploring biologically plausible information processing based on higher order temporal coding. SNSDN was proposed as an alternative solution to the binding problem [1]. SNSDN operation resembles Stochastic Diffusion Search, SDS, a nondeterministic search algorithm able to rapidly locate the best instantiation of a target pattern within a noisy search space [2, 3]. In SNSDN, relevant information is encoded in the length of interspike intervals. Although every neuron operates in its own time, ‘‘attention’’ to a pattern in the search space results in self-synchronised activity of a large population of neurons. When multiple patterns are present in the search space, ‘‘switching of attention’’ results in a change of the synchronous activity. The qualitative effect of attention on the synchronicity of spiking behaviour in both time and frequency domain will be discussed. REFERENCES 1. Bishop, J. M., & Nasuto, S. J. (1998). Neural Stochastic Diffusion Search Network—A Theoretical Solution to the Binding Problem. Proceedings of the ASSC2, Bremen. 2. Bishop, J. M. (1989). Stochastic Searching Networks. Proceedings of the 1st IEE Conference of the ANNs. London. 3. Nasuto, S. J. (1999). Resource Allocation Analysis of the Stochastic Diffusion Search. Ph.D. Thesis, University of Reading.

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Poster Session 2—July 1, 2000

P2-01. Visual Object Priming in Patients with Retrogeniculate Lesions. Silke Jo¨rgens, Michael Niedeggen, & Petra Stoerig, Institut of Physiological Psychologie II, Heinrich-Heine-Universita¨t Du¨sseldorf, 40225 Du¨sseldorf, Germany. E-mail: [email protected]. Hemianopic patients may show blindsight, a capacity to detect, localize, and discriminate visual stimuli presented within the defect and of which they are not aware. With a priming paradigm, we tested form discrimination, the most controversial of these residual visual functions, in 7 patients and 15 controls. Three patients were experienced subjects with long-standing lesions (⬎15 years), three comparatively acute (⬍6 months), and one was tested soon after the insult and following 6 months of blindsight training. The patients tasks was to categorize black-and-white drawings of animals and food items which were presented in the normal hemifield. Target presentation was preceded (ISI 150 ms) by a 200-ms stimulus in the impaired hemifield, which was neutral (e.g., random dots–cat), identical (e.g., cat–cat), of the same (e.g., horse–cat) or the other category (e.g., carrot–cat). In controls, identical primes decreased RTs significantly (delta RT ⫽ 93 ms). The experienced (delta RT ⫽ 77 ms), but not the untrained (delta RT ⫽ 29 ms) patients showed a comparable identity effect for the animal category. In the patient who was tested twice, effect size increased from 18 ms (n.s.) to 45 ms ( p ⬍ .05). Form processing in the impaired field can be revealed with priming, and may depend on the time-since-lesion and/ or training. P2-02. Aware or Unaware? Signal Localisation and Detection in a Field of Relative Cortical Blindness. A. Zontanou, P. Stoerig, & A. Cowey, Institute of Physiological Psychology, Heinrich-Heine-University, Building 23.03, Universittsstrasse 1, D40225 Du¨sseldorf, Germany. E-mail: [email protected]. Blindsight reveals a dissociation between visual performance and awareness in patients with visual field defects from retrogeniculate lesions. To determine whether a signal detection paradigm we previously used in monkeys (Cowey & Stoerig, Nature 373, 1995)could capture this dissociation non-verbally, tested a well-studied patient with a relative hemianopia (GY). 2AFC localization was measured as a function of stimulus contrast; in addition the patient indicated whether he had been aware of the stimulus. Results show that at 30% contrast he performed significantly above chance, yet claimed to be unaware. With increasing contrast, correct localization and aware-responses increased. In the second test, GY was to respond to stimuli by touching their position wherever they appeared, but in addition to respond to blanks by touching a no-stimulus response area on the VDU. 60% of stimuli appeared in his normal field; the remaining were blanks, except that in some series 5 or 20% were replaced by probe targets in the impaired field. While probes below the awareness threshold were always classified as blanks, those above were classified appropriately throughout. The pattern of results validates the paradigm as a non-verbal method of capturing the difference between an explicit, aware, and an implicit, unaware, mode of visual processing.

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P2-03. Visual Awareness of Objects as Revealed by EEG. Maria Wilenius-Emet & Antti Revonsuo, Centre for Cognitive Neuroscience, University of Turku, FIN-20014 Turku, Finland. E-mail: [email protected]. The aim of the present study was to shed more light on the neural correlates of visual awareness and binding by examining event-related potentials (ERPs) during an object detection task. The present EEG study was a replication of the MEG study by Vanni et al. (1996). Ten right-handed healthy adults participated in the study. Two types of black-and-white line-drawings were used as stimuli: objects and nonobjects. The pictures of objects were selected from the standardized stimulus set of 260 pictures by Snodgrass & Vanderwart (1980). The corresponding non-objects were selected from the stimulus set of scrambled objects that was generated and used by Vanni et al. (1996) by randomly rotating circular areas within the object drawings until the object became completely disorganized and unrecognizable. Three different stimulus durations were used to vary the rate of conscious object detection; the masked stimuli were presented for the participant below, at, and above the recognition threshold in consecutive stimulus blocks. After each stimulus the participant responded by pushing one key if he had seen a coherent object, another key if he had seen a disorganized non-object, and a third key if he had failed to see whether the stimulus was an object or a nonobject. While the participant was performing the task, EEG was recorded using 20 scalp electrodes arranged according to the 10/20 system. The main finding was a prominent negative ERP-component that occurred at around 265 ms after stimulus onset for threshold, but not for any stimuli shown below the threshold. The N265 component thus seems to correlate with the crossing of the recognition threshold and it might reflect the neural correlates of visual awareness or be a necessary condition for visual awareness to occur. P2-04. On the Psychological Plausibility of Binding by Synchrony. Jacques P. Sougne´, University of Lie`ge, Bat B32 Sart Tilman, 4000 Lie`ge, Belgium. E-mail: [email protected]. Temporal synchrony has been proposed as a neurally plausible solution to the binding problem (von der Marlsburg, 1981; Singer, 1993) and as a potential neural correlate of conscious behavior (Crick & Koch, 1990; Engel, Fries, Knig, Brecht, & Singer, 1999). Several neurobiological studies have provided support for this hypothesis. This contribution explores the psychological plausibility of temporal synchrony binding to explain human abilities related to consciousness. Consciousness seems to require attentional mechanisms, a working memory, and the ability to develop structured representations (Engel et al., 1999). A computational model of spiking neurons (INFERNET) using temporal synchrony as a binding mechanism was used for the study of working memory and structured representation. Simulations were compared with empirical data. If these simulations had led to performance inconsistent with empirical data, it would cast doubt on temporal synchrony as a plausible mechanism for binding. But INFERNET has performance and limits comparable with human behavior. It has a limited working memory span, displays serial effects and similarity effects, and can simulate double dissociation between long and short-term memory. INFERNET can also simulate various reasoning tasks like relational, disjunctive and

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conditional reasoning, while displaying for these tasks limitations similar to those of humans. P2-05. When Do Speed and Accuracy Agree or Disagree? A Binding Explanation. Peter Wu¨hr, Gu¨nther Knoblich, & Jochen Mu¨sseler, Max-Planck-Institut fu¨r psychologische Forschung, Amalienstrasse 33, 80799 Munich, Germany. E-mail: wuehr@ mpipf-muenchen.mpg.de. Similar distractors speed up the response to a visual target stimulus, whereas dissimilar distractors delay responding (Eriksen & Eriksen, 1974). However, Santee & Egeth (1980) report that similar distractors impair target identification. Experiments by Keren & Boer (1985) demonstrate that similar distractors may improve target identification, if target position is known in advance. The mechanisms underlying this positional effect remain largely unspecified. We propose a binding mechanism that may provide a means to give a coherent explanation for the seemingly discrepant pattern of results. Binding the identity and the position of the target stimulus is a necessary condition for both, correct identification and fast responding. If the correct stimulus identity is bound to the wrong (distractor) position, performance is impaired in terms of speed and accuracy. In addition, binding stimulus properties requires focused attention. Thus, increasing the likelihood of attending to the position of a distractor will increase the negative effects of the distractor. We tested this prediction in four experiments. The similarity and the temporal relation between distractor and target, and the predictability of the target position were varied. Besides replicating the results described above, the experiments provide new evidence for our binding explanation. P2-06. Extinction-Like Effects in a Spatio-Temporal Attention Task: A Transient Neglect in Normal Observers? Guido Hesselmann & Michael Niedeggen, Institute of Physiological Psychology II, Heinrich-Heine University, Universitaetsstrasse 1, D-40225 Duesseldorf, Germany. E-mail: [email protected]. Selective attention is usually studied by investigating either its spatial aspect as in visual search or its temporal aspect as in rapid serial visual presentation. We combined both aspects, presenting a 5 ⫻ 5 grid (6 ⫻ 6), in which 20 random letters where singly presented at random positions at 13 letters/s. A target consisting of one (1DT) or two—simultaneously presented—digits (2DT) was embedded among the letters. 10 subjects were asked to indicate the number and identity of the target. No distractor was presented in the same square immediately before or after the target. While 1DTs were easily identified, one digit was often neglected (error rate: 25%) in the 2DT. Spatial distance was less important than position, showing that the diameter of the attentional spotlight is not the limiting factor. The deficit was exacerbated (43%) when distractors following the target appeared close to the position of either digit. As the distractors do not appear at the physically identical position, the effect cannot be caused by proper backward masking of the digit. Unless we confront here a spatially imprecise form of backward masking, it could reflect an attentional overload related to simultaneous extinction.

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P2-07. Binding of Stimulus and Response Features after a Task Switch. Bianca Po¨sse & Bernhard Hommel, Max-Planck-Institute for Psychological Research, Department Cognition & Action, Amalienstrasse 33, D-80799 Munich, Germany. Email: [email protected]. Hommel (1998) hypothesised that the features of a given stimulus and a given response have to be integrated in an event-file before a reaction can take place. The results of several experiments support this interpretation. They demonstrate that both repeating and completely alternating stimulus and response features improve performance. In contrast, partial repetition of these features impairs performance. In the present experiments, we investigated whether effects of the binding of stimulus- response features are also present after a task switch. Participants responded to stimuli that varied on two dimensions, e.g., colour and form. The stimulus-response mapping was variable. At the beginning of each trial, verbal or visual cues indicated which stimulus dimension the participant should react to and which stimulus-response mapping should be used. In some trials there was a switch from the form to the colour task or vice versa, in some trials the same task was repeated. We replicated Hommel’s findings for task repetition. Both repeating and alternating stimulus and response features improved performance, when a task was repeated. However, after a task switch such binding effects were largely reduced. A simple explanation for this result is that existing bindings are deleted after each task switch. P2-08. The Binding Function of Linguistic Signs. Gisela Fehrmann & Erika Linz, Center for Cultural Research Media and Cultural Communication, University of Cologne, Bernhard-Feilchenfeldstrasse 11, D-50969 Koeln, Germany. E-mail: [email protected], [email protected]. This paper focuses on the thesis that linguistic signs provide a central binding device for the creation of mental concepts—here referred to as secondary categorization. ‘‘Secondary categories’’ are those categories that do not result from direct perceptuomotor experience, i.e., all forms of functional and cultural determined categories like tool, furniture, mammal etc., likewise all kinds of abstract and relational categories. Taking up nonrepresentational semiotic tradition (5–7, 11) we argue for the constitutive impact of linguistic signs on secondary classification. Relying on correlative frameworks (1, 2, 9, 10, 12), we consider conceptual contents to be represented in a dispositional and parcellated way. Meaning is not stored in a stable and discrete manner but has to be reconstructed from instantiation to instantiation. Linguistic signs provide a means to bind a multiplicity of different modal and functional feature fragments in a new unimodal format. By means of linguistic binding devices perceptuomotor fragments as well as primary categories are reorganized discursively as symbolic units under the control of linguistic network constraints. The linguistic semiosis establishes a new kind of cognitive unit by building up a modal format without re-presenting any concrete conceptual-sensory information. Since linguistic signs symbolize concepts in an arbitrary but nevertheless modal way the concepts become consciously available without requiring the retroactivation of sensory images. Therefore, the linguistic sign not only leads to economic processing but also

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allows the cognitive manipulation of fictional, abstract and relational knowledge (3– 5, 8). REFERENCES 1. Damasio, A. R. (1989). Time-locked multiregional retroactivation. A systems-level proposal for the neural substrates of recall and recognition. Cognition, 33, 25–62. 2. Damasio, A. R., & Damasio, H. (1994). Cortical systems for retrieval of concrete knowledge: The convergence zone framework. In C. Koch & J. L. Davis (Eds.), Large-scale neuronal theories of the brain (pp. 61–74). Cambridge, MA, London: MIT Press. 3. Deacon, T. W. (1997). The symbolic species. New York/London: Norton. 4. Dennett, D. (1998) Reflections on language and mind. In P. Carruthers & J. Boucher (Eds.), Language and thought. Interdisciplinary themes. Cambridge: Cambridge University Press. 5. Fehrmann, G. (1999). Verzeichnung des Wissens. Ueberlegungen zu einer neurosemiologischen Theorie der sprachgeleiteten Konzeptgenese. Diss. Aachen. 6. Hegel, G. W. F. (1970). [1832ff]: Werke in 20 Baenden, Bd. 10, Teil: Die Philosophie des Geistes. Frankfurt a. M.: Suhrkamp. 7. Jaeger, L. (1998). Die Medialitaet der Sprachzeichen. Zur Kritik des Repra¨sentationsbegriffs aus der Sicht des semiologischen Konstruktivismus. In M. Lieber & W. Hirdt (Eds.), Kunst und Kommunikation. Festschrift zum 60. Geburtstag von Richard Baum (pp. 199–220). Tuebingen: Stauffenburg (English version in press). 8. Linz, E. (1999). Indiskrete Semantik. Kognitive Linguistik und neurowissenschaftliche Theoriebildung. Diss Aachen. 9. Mesulam, M. M. (1998) From sensation to cognition [review]. Brain 121, 1013–1052. 10. Roelfsema, P. R., Engel, A. K., Koenig, P., & Singer, W. (1997). Visuomotor integration is associated with zero time-lag synchronization among cortical areas. Nature 385, 157–161. 11. de Saussure, F. (1968). Cours de linguistique ge´ne´rale. E´dition critique par Rudolf Engler. Tome 1–2: Reproduction de l’e´dition originale. Wiesbaden: Harrassowitz. 12. Singer, W., Artola, A., Engel, A. K., Koenig, P., Kreiter, A. K., Loewel, S., & Schillen, Th. B. (1993) Neuronal representations and temporal codes. In T. A. Poggio & D. A. Glaser (Eds.), Exploring brain functions (pp. 179–194). New York: Wiley.

P2-09. Incidental Action-Outcome Learning Influences Intentional Response Selection. Birgit Elsner & Bernhard Hommel, Max-Planck-Institute for Psychological Research, Department Cognition and Action, Amalienstrasse 33, 80799 Munich, Germany. E-mail: [email protected]. Actions are performed to attain desired effects or consequences, hence, to intentionally produce particular events. Thus, knowledge about the consequences a movement is likely to produce provides an important basis for voluntary action control. In several experiments, we showed that knowledge about irrelevant movement-event relationships, which had been acquired non-intentionally, has an impact on the voluntary execution of future movements. In the first phase of our experiments, subjects perceived sensory events (e.g., tones of a certain pitch) that contingently followed particular movements (e.g., presses on certain keys). This seems to trigger an automatic, non-intentional integration of the representations of the movement and of the following event. The effects of this integration reveal in the second phase of the experiments, where subjects had to respond to the former post-response tones by

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pressing certain keys. Our results corroborate the assumption that the concerned movement is primed whenever the integrated event is perceived, this leading to better performance when this movement has actually to be performed. Taken together, our experiments provide converging evidence that incidental learning about movements and their consequences influences intentional action control. P2-10. The Unity of the Concept of Consciousness. Michael Schmitz, Philosophisches Institut, Freie Universita¨t Berlin, Emser Strasse 125, 12051 Berlin, Germany. E-mail: [email protected]. Contemporary discussions of consciousness often begin by distinguishing several senses of the term, for example, consciousness in the sense of creature consciousness, of being awake, of phenomenal consciousness or of intentionality. Using some insights from the linguistic theory of word meaning, I argue that, while in some rather weak sense different senses may indeed be present here, the distinctions drawn by many authors are overly sharp, and sketch a more unified account of the concept of consciousness. The concept of the intensity or degree of conscious experience plays a key role in this account, as it is applicable to all the different varieties of conscious experience. Because it is so comprehensive, it is also useful in characterizing global states of consciousness such as being awake or dreaming. Further descending in the order of comprehensiveness or generality, I then turn to states like believing, desiring, seeing and so on. In order to explain the relation of these states to the general condition of being conscious, an analogy with the relation between the condition of being in a liquid state and the things in this state will prove to be useful. P2-11. A Computational Model for Binding Sensory Modalities. Emanuelle Reynaud, Agne`s Crepet, He´le`ne Paugam-Moisy, & Didier Puzenat, Institut des Sciences Cognitives, 67 boulevard Pinel, 69675 Bron Cedex, France. E-mail: reynaud@ isc.cnrs.fr. The aim of our work is to build a computational model of a memory that could bind together different sensory information coming from the same object. Starting from the functional architecture proposed by Kosslyn & Koenig for visual and auditive high-level perception, we assume that this architecture can be extended to each sensory modality and that (1) recognition is processed in parallel within each modality; (2) a multi-modal associative memory integrates the available recognized patterns to identify the object; (3) some feedback mechanisms can be turned on if the multi-modal memory cannot identify the object. To implement this theory, we have built a modular connectionist model from basic artificial neural networks, and defined the cooperation in both bottom-up and top-down ways. Recognition is performed by prototype-based classifiers, one for each modality. As the multi-modal associative memory, a recurrent network performs the binding process: a bidirectional associative memory has been adapted with multiple input layers encoding perceptive prototypes. This model has been tested on artificial data sets, accounting for bimodal objects. Performances are good and even enhanced by feedback mechanisms. More-

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over, the model simulates several cognitive phenomena such as mental image evocation and correct identification even if a modality-specific prototype is missing. P2-12. Automaticity of Semantic and Syntactic Processing. Dana Ganor & Joseph Tzelgov, Department of Behavioral Sciences, Ben-Gurion University, Beer-Sheva 84105, Israel. E-mail: [email protected]. Automaticity of semantic and syntactic processing of two-word sentences was studied using an interference paradigm. In one experiment subjects made semantic judgements (i.e., Is the sentence meaningful or not?) while ignoring grammatical correctness, or they made grammatical judgments (i.e., Is the sentence grammatically correct or not?) while ignoring meaningfulness. In another experiment subjects decided whether the two words of the sentence appeared in the same color. Results of the first experiment have shown that grammatical judgments were slower for meaningless sentences than for meaningful ones, indicating automatic processing of meaning. However, semantic judgments were slower for grammatically incorrect sentences compared to correct ones only when these judgments were preceded by grammatical judgments. By contrast, results of the second experiment have shown that color judgments were not influenced by the meaningfulness or by the grammatical correctness of the sentences. Taken together these results imply that both meaning and syntax can be processed automatically, i.e., without monitoring. However, automatic processing of syntax requires previous activation of the grammatical processor. In addition, automatic processing of both meaning and grammar occurs when the requested task results in representations of the presented stimuli as verbal units (rather than color patches). P2-13. Artificial Grammar Learning in Amnesia. Thierry Meulemans & Martial Van der Linden, University of Lie`ge, Neuropsychology Unit, Boulevard du Rectorat B33, B-4000 Lie`ge, Belgium. E-mail: [email protected]. The purpose of this study was (a) to investigate the validity of an explicit generation-task in order to assess the explicit knowledge acquired in an artificial grammar learning task; (b) to explore the implicit learning abilities in a group of nine amnesic patients by using an artificial grammar learning task in which classification performance could not be based on the learning of simple associations between elements of the learning material. The main result of Experiment 1 is that performance in the generation task is specifically related to information learned during the study phase and not to information presented during the classification phase. Results of experiment 2 show that amnesic patients and controls performed at the same level during the classification task, whereas amnesic patients performed worse than controls in the generation task. These results are compatible with the existence of two kinds of representation intervening in artificial grammar learning: one based on processes leading to fragment-specific knowledge (which can be accessed explicitly); the second based on implicit associative learning of complex conditional relations between elements. It is on this latter mechanism that depends the subjects’ performance in the classification task.

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P2-14. Reexposure and Release of Retrieval Inhibition. Barbara H. Basden & David R. Basden, Department of Psychology M/S PH11, California State University, Fresno, California 93740-8019. E-mail: [email protected]. Release of retrieval inhibition occurs when reexposure to inhibited items eliminates directed forgetting. Bjork & Bjork (1996) proposed that reexposure to part of the inhibited list (List 1) releases retrieval inhibition when the memory episode for that list is consciously remembered. However, in the experiments reported here, conscious recollection of List 1 appeared to be nonessential, in that implicit (indirect) reexposure tasks (pleasantness rating, word fragment completion) were as effective as an explicit (direct) task (recognition) in releasing retrieval inhibition. Percentage of list members reexposed strongly influenced the release of retrieval inhibition. Directed forgetting remained intact when 0 or 25% of the list members were reexposed but was no longer detectable when 50, 75 or 100% were reexposed. We concluded that directed forgetting was reduced largely through renewed access to reexposed List 1 items rather than through conscious recollection and reinstatement of the entire List 1 episode. P2-15. The Continuity of Self in Collectivism and Individualism. William P. Banks, Kris Y. Yi, Angela V. Lumanau, & Nancy Chen, Department of Psychology, Pomona College, Claremont, California 91711. E-mail: [email protected]. One important factor in the unity of consciousness is the self, which provides a resource for continuity, a reference for memories, and a coherent interpretation of reality. Cultural factors are essential to the construction of the self. The dimension of individualism and collectivism emerges as a universal classification of societies, and this is explicitly a dimension that concerns the structure of the self. We found that individualistic respondents (American college students) and collectivistic respondents (college-age Japanese citizens) had, surprisingly, almost identical degrees of the self-reference effect in memory (the finding that a list of random trait adjectives, when judged as applicable to one’s self, are easier to remember and recall than a list of the same adjectives learned using other methods). We also compared the two groups in the fundamental attribution error. We found the typical error for the individualistic participants, but a great reluctance by the collectivistic participants to make any attribution at all. Finally, we showed that a state of war (an intercollegiate game) causes American team members to become more collectivistic and to have simpler out-group stereotypes, and more complex and positive in-group attributions, than a non-war state. Implications for continuity and self cross-culturally will be discussed. P2-16. Agency and the Unity of Self-Consciousness. Mirko von Elstermann, RuhrUniversity Bochum, Institute for Philosophy, Hermeskeiler Strasse 34, D-50935 Cologne, Germany. E-mail: [email protected]. In my project I want to examine the extent to which agency, a subject’s ability to realize action plans in controlled behaviour sequences, contributes to the apparent unity of physical and psychological (or, in a different conceptualization, ecological and interpersonal) self-consciousness. The neuropsychology of autism, among other

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psychiatric diseases, makes evident that this unity can be disrupted, and that in the normal individual there are neural and psychological mechanisms which integrate these components of the self. In a philosophical perspective I will first analyze the conceptual relations between agency and the mentioned aspects of self-consciousness. After this conceptual clarifying, psychological and neural processes will be discussed by which agency and the awareness of agency are supposed to arise; on this basis I will try to explain how a construct of a unified self could emerge, acting in the physical realm and at the same time relating itself to others. In this philosophical proposal I will strongly refer to results in developmental psychology (especially concerning joint attention, theory of mind, and executive functions) and neurobiology (here regarding the neuronal implementation of agency and the recognition of agency components, for, e.g., by ‘‘mirror neurons’’). P2-17. A Neural Model of Cognition & Consciousness. Garry Briscoe, Computer Science Department, University of Wisconsin Oshkosh, 800 Algoma Boulevard, Oshkosh, Wisconsin 54901. E-mail: [email protected]. A neural model of cognition based on recurrent linkage of topological maps at various levels is proposed in which the mechanism of cognition is the learning of temporal sequences linking sensory inputs to output behaviors. The neural structure affords a novel view of consciousness. In this view, implicit ‘‘knowledge’’ and resultant behavior is brought about via perceptual learning. Perceptual attractors and temporal sequences are learned from incoming sensory experiences, and result in output behaviors that are not attached to verbal awareness. Perceptual learning then is a mechanism whereby a learned connection is formed between sensory inputs and resulting behavioral outputs. Differential perceptual inputs result in different behaviors; i.e., perceptual conceptualization. While perceptual conceptualization does not involve language, the labelling of perceptual attractors allows for much richer and complex concepts to be formed. The process of labelling of perceptual concepts is not one of ‘‘learning the meaning of words’’ in the usual sense, but rather, one of attaching an arbitrary label to an already established ‘‘perceptual’’ meaning unit. In the model, language comes about when verbal utterances are associated with perceptual attractors, and also form temporal sequences themselves. Output behavior from such verbal attractors and sequences is speech and self-talk (a proposed linguistic recurrent linkage within the brain), and these are the mechanisms of reporting to others and ourselves, respectively. The attached labels are able to be formed into verbal (and self-talk) sequences to reference the specific experience or object, and this is proposed as the mechanism of explicit recognition and conscious awareness. The model proposes a mechanism for the process of inner linguistic thinking—a linkage within the human brain that connects an area adjacent to the vocal motor areas, to another area adjacent to (or coincidental with) the auditory input region. Linguistic thought (self-talk) is then the learning of sound equivalent codes via this internal recurrent linkage. Rather than the external mouth-sound-ear linkage of language, this is a direct neural linkage formed within the cortex. The internal linkage provides an additional source of ‘‘sound’’—the silent sound of verbal thinking. Provided that these voice-equivalent vector components are able to be learned, there is

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now another source of verbal instructions or communication that is self-generated. Explicit ‘‘knowledge,’’ then, is knowledge that is available to be reported (via language or self-talk) because labels and language sequences are attached to perceptual attractors. It is not until we report to ourselves via labels associated with a viewed object that we explicitly identify (i.e., recognize) it. Many neurological deficits may come about as a result of a break (via some ablation) in the linkage between perceptual concepts and linguistic sequences, an apparent severing of the ‘‘normal’’ access to conscious awareness. The paper discusses several deficits in this light, including blindsight. Within the model, consciousness may be seen as being made up of multiple components, including sensory awareness through perceptual conceptualization, self-talk (or inner linguistic thought), and mental imagery resulting from internal recurrency within the visual system. The unity of consciousness results from the association of the various sensory neural components into a composite whole within the model and their linkage to motor and other behaviors. The proposed model enables a new perspective to be taken on consciousness, and is able to provide an explanation of many of the properties of consciousness awareness. Computer simulations of the basic structures that comprise the model will be discussed. P2-18. The Body as Cognitive Organiser. Grant Blundell-Wignall & Marjorie Collins, 78 Solomon Street, Fremantle, Western Australia 6160, Australia. E-mail: [email protected]. In a series of studies using word-recognition priming in the cerebral hemispheres, we are investigating a claim made by some cognitive linguists: that important cognitive schema derive their structures from the metaphoric projection of basic dimensions of bodily experience onto language. The data presented are from two experiments. Initially, we used prime-target pairs in which paired words were related by a generic mix of metaphors comprising both spatial and non-spatial content. When pair members were independently directed to either the left (LH) or right (RH) hemisphere, the resulting pattern of primed recognition suggested that the RH plays the primary role in accessing metaphoric word-meanings. Next, we compared two metaphor sets, one generated exclusively from body dimensions as defined by the cognitive linguists, the other devoid of bodily or spatial reference. While body metaphors elicited a pattern similar to our initial finding, non-body metaphors elicited a quite different effect: priming occurred only for targets directed to the LH. This suggests that the body/non-body distinction is reflected in cognitive organisation. Together, the results indicate that the contribution of bodily experience to cognitive organisation is worthy of further investigation. P2-19. Disassociation of Lexical and Color Pattern Implicit Learning in Schizophrenic Patients. Kristina Liu, Ming H. Hsieh, Shi K. Liu, Hai-Gwo Hwu, & MingJang Chiu, University of Washington, 4212 210th Place Northeast, Redmond, Washington 98053. E-mail: [email protected]. Disruption of implicit sensory processing in schizophrenic patients was evidenced in numerous latent inhibition studies. Latent inhibition effects (LI) can be described as adaptive learning that filters out irrelevant stimuli. Current research indicates two

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explanations, the dopamine and attention dysfunction hypotheses, that predominately account for the inability of schizophrenic patients to effectively utilize LI effects when learning. The perceptual representation system hypothesis offered a third alternative. This study employs an implicit learning paradigm to investigate schizophrenic patients’ ability to do implicit sensory processing. Implicit learning refers to the development of intuitive knowledge about the underlying structure of a complex stimulus environment. Computerized images were used to more accurately and consistently control the presentation of stimuli. In addition to letter strings, color patterns regulated by artificial grammars are also employed. A forced choice instant deja-vu method was used to measure the effects. We recruited 20 patients of schizophrenia for investigation. Significantly different results were found between the traditional letter strings and the new color pattern stimuli. Schizophrenic patients performed as well as non-schizophrenic subjects when using letter strings to do implicit learning but were unable to process color pattern stimuli as well. P2-20. The Unity of Consciousness Envisaged from Dissociative States. Paloma Enriquez & Eduardo Mino, Department of Psychobiology, UNED, Ciudad Universitaria, 28040 Madrid, Spain. E-mail: [email protected]. The current use of the term consciousness includes a variety of phenomena captured in two approaches: consciousness as a functional mechanism (e.g., access and monitoring), and consciousness as a state (awareness). The former refers to control processes related to executive function, while the later calls upon the subjective experience—the core aspect of consciousness-, involving a particular state: that of being aware. An important point in relation to conscious awareness refers to the unity or disunity of subjective experience. Subjective experience is characterised by a feeling of unity that underlies the intuitive idea of a unified self. However, several phenomena as those observed in anosognosia, hypnosis and dissociative states undermine a unitary conception of conscious experience. It seems that the integrated subjective experience emerges as a result of active mechanisms susceptible to selective disruptions instead of depending on a single system responsible of the unity of conscious experience as a whole. In this context, this presentation will focus on the breakdown of an integrated subjective experience observed in dissociative disorders. It will be posed the extent in which dissociative experiences could occur in non-pathological conditions, suggesting that gaps in the integration of subjective experience may be broader than what psychopathology shows. P2-21. My Amygdala-Orbitofrontal-Circuit Made Me Do It. Bill Faw, BrewtonParker College, Highway 280, Mount Vernon, Georgia 30445. E-mail: faw@ cybersouth.com. I have suggested that the prefrontal cortex constitutes an executive committee (instead of merely Baddeley’s executive), with five streams (instead of merely Baddeley’s visuo-spatial sketch-pad and auditory articulatory loop) coming from posterior cortex and subcortical areas to five pre-frontal executive regions (dorsolateral, anterior cingulate, Broca’s-plus, orbito-frontal, and polar frontal), each of which chairs

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at least one on-going sub-committee (involving its input streams and its basal ganglia/ thalamic processing loops) and vies with the other executives for taking over central control of conscious attention and willed action (through its premotor/motor output pathways). It is through the dynamic interaction of this executive committee that unified conscious experiences and a sense of continuous self-identity are created. There is growing evidence that the amygdala-orbitofrontal brain circuit, in particular, is crucial to impulse control, knowledge of good and evil, personality, personhood, and even how x-me made y-me do something. I will cite striking examples of the ways that orbitofrontal and anterior cingulate committee members can stage an insurrection against the dorsolateral prefrontal cortex executive chair. P2-22. Implicit Knowledge and Logical Categorisation. Tatiana Rebeko & Ekena Nikitina, Institute of Psychology of RAS, Yaroslavskaya, 13, 129366, Moscow, Russia. E-mail: [email protected]. We suggested that implicit knowledge influenced in results of category formation. The experiments were carried out with the 30 cards each of them composed by the three types of figures fulfilled by the three types of textures. In the first and third experiments, the subjects had to judge the similarity of each of the 30 cards with the set of isolated figures and textures. In the second experiment, the subjects had to arrange all of these 30 cards in the artificial category according to the two unknown rules. Depending on a successfulness of category formation, the subjects distributed in the four groups. The subjects from the most successful group judged the similarity by applying on relevant characteristics of the artificial category even before they formed it. These relevant characteristics consisted in primitive proportions of figures and textures. The subjects could not resume the explicit rules; moreover, this implicit knowledge was more precisely than explicit knowledge and it improved from the first experiment to the third one. The subjects from the less successful group after failed attempts to form an artificial category used to fix the irrelevant characteristics of stimuli. (The research is supported by RFFI, Grant 00-0680145.) P2-23. Schematic and Reflexive Processing during an Emotional Imagery Task. Alexandre Schaefer & Pierre Philippot, Universite´ Catholique de Louvain, Faculte´ de Psychologie, 10, Place du Cardinal Mercier, 1348 Louvain-La-Neuve, Belgium. E-mail: [email protected]. Classic theories of emotion suggest that emotion is elicited by the activation of a unique type of representation code (e.g., Bower, 1981, 1991). This postulate raises several problems, such as the difficulty of accounting for the distinction between hot and cold processing of emotions (Teasdale, 1999). The dual-memory system model of emotion (Philippot & Schaefer, In Press) postulates the existence of two emotional information processing systems which yield qualitatively distinct subjective experiences: The Schematic system is an implicit level of emotional processing responsible for the elicitation of hot emotional feelings. The Reflexive system is a conscious and controlled level of emotional processing which generates cold processing of emotional information. The present study tested the prediction that the activation of the

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schematic system should generate stronger emotional feelings as compared to the activation of the reflexive system. In order to manipulate the schematic or reflexive nature of processing, the participants were constrained to adopt an evaluation mode which induced a schematic or reflexive processing by mentally pronouncing sentences read by the experimenter while they were performing an emotional imagery task. 60 participants randomly assigned to three between-subjects conditions had to imagine five emotional scenes. In the schematic condition, metaphoric sentences from Smith & Lazarus (1993) relational themes were used, whereas in the reflexive condition, the sentences were explicit questions about emotional appraisal elements of the imagery scenario. In the control condition, no sentences were mentally pronounced during the imagery task. Congruent with our hypothesis, the schematic condition yielded stronger self-report and SCL (skin conductance level) scores of emotional intensity compared to the reflexive condition. REFERENCES Bower, G. H. (1981). Mood and memory. American Psychologist, 36, 129–148. Bower, G. H. (1991). Mood congruity and social judgment. In J. P. Forgas (Ed.), Emotion and social judgments. Oxford: Pergamon Press. Philippot, P., & Schaefer, A. (in press). Emotion and memory. In T. J. Mayne and G. A. Bonano (Eds.), Emotion: Current issues and future directions. Guilford Press. Teasdale, J. D. (1999). Multi-level theories of cognition-emotion relations. In T. Dalgleish & M. Power (Eds.), Handbook of cognition and emotion (pp. 665–681). Chichester, England: Wiley. Smith, C. S., & Lazarus, R. S. (1993). Appraisal components, core relational themes, and the emotions. Cognition and Emotion, 7, 233–269.

P2-24. Phenomenological Recollection of Autobiographical Events: The Contribution of Language and Imagery. Aniko´ Ko´nya, Ildiko´ Kira´ly, & Anett Rago´, Institute of Psychology, ELTE, 1064 Budapest Izabella utca 46, Hungary. E-mail: konya@ izabell.elte.hu. Our purpose is to demonstrate that conscious recollection of autobiographical memories simultaneously emerges from language and imagery processes. On the one hand we analyse the conceptual structure of verbally recalled memories. We propose that the level of concepts used in recall depends on the phenomenological vividness of memory. Different types of natural language categories emphasize the decomposability of the event memory. According to Barsalou (1988) we wanted to show that memory is based on conceptual structure and gets to a higher level of abstraction. Furthermore we suppose that this level is different in the case of various conceptual components of memory. This argues for the phenomenal complexity of memory. We studied the different levels of concepts in the texts of so-called first memories recalled by student subjects as a function of the vividness of memory and the spatial construction of the event. Measures of vividness were gained through introspective methods. As for imagery the spatial resolution gets better with increasing phenomenal vividness. This is also illustrated by the spatial localization of memory fragments, which can be monitored by drawing and verbal inquiring techniques as well.

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P2-25. Automatic Stimulus–Response Associations Are Semantically Mediated. Bert Reynvoet, Bernie Caessens, & Marc Brysbaert, Faculty of Psychology and Educational Sciences, Department of Experimental Psychology, H. Dunantlaan 2, 9000 Ghent, Belgium. E-mail: [email protected]. Three experiments on numerical odd/even judgment are presented. In the first experiment, we show that tachistoscopically presented Arabic primes influence the reaction latencies to Arabic targets: RTs to targets are longer when prime and target have a different parity status than when they share the same parity status. Experiments 2 and 3 extend this finding, by showing that the response compatibility effect is also obtained (1) when the primes are not part of the target set and the participants never reacted to them, and (2) when the primes are presented in a different modality (verbal numerals) than the targets (Arabic numerals). On the basis of these results, we conclude that response codes are automatically activated by stimulus characteristics and that the activation of response codes is semantically mediated when the stimuli are meaningful. This interpretation explains why the stimulus-response associations generalize to stimuli that do not belong to the target set and why they are observed with primes that have no physical overlap with the targets. P2-26. Resilience and Posttraumatic Stress Disorder (PTSD): The Threat to Physical Integrity as a Study Model of the Dynamics of the Information Integration. Luc Decleire, Institut de Chaopathologie (ICPL), Ge´ne´ral Five´ street, 88, B-1040 Brussels, Belgium. E-mail: [email protected]. The reactions to a threat to the physical integrity of self or others are individual. Face to the same trauma, lot of people can develop a PTSD (DSM-IV criteria) when others will be considered as resilient. War conditions (as those recently studied in Kosovo), hardships of all nature can create such a hostile environment that every adaptative strategy of the subject to protect his integrity will lead to a total failure. In those conditions, stereotyped symptoms—including dissociative behaviours—can appear and be identified as a PTSD. Many things can trigger these symptoms during sometimes more than 75 years. Amongst the resilients, a part of them already had dissociative symptoms (schizoid, schizophrenic or psychopaths) and another part had already developed—due to hard life circumstances in childhood—lasting clusters of self-protective behaviours. If we reduce those dramatic situations in an integration process of information in parallel neuronal networks, we can—by analogy—suppose that dissociation (as a disruption in the usually integrated functions of consciousness, memory, identity, or perception of the environment) should not be considered inherently pathological but also as a rough protection system like a cut-out between different networks.

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P2-27. Working Memory Ability: Electrophysiological Correlates of Performance on Cognitive Tasks. Adrienne E. Eastwood, Richard A. Steffy, & William C. Corning, Department of Psychology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. E-mail: [email protected]. It has been demonstrated that electroencephalogram (EEG) slow wave activity (SW) occurs more frequently in children with learning disabilities than in normally functioning children (e.g., John et al., 1977). However, the specific cognitive deficits exhibited by children that are related to SW remain less clear. Insofar as brain activity normally shifts with age to faster rhythms (with a concomitant decrease in synchrony), and cognitive abilities become more complex with age, the proportion of SW in a child’s EEG may provide an index of his/her capacity to co-ordinate multiple cognitive functions. From this view, we hypothesized that excessive SW would be most evident in individuals who have difficulty managing processing-rich cognitive tasks (e.g., working memory). 85 children between the ages of 8 and 16 were administered a quantitative EEG and cognitive tests graded according to working memory requirements. We found that the cognitive tasks making the most demands on working memory were significantly and negatively correlated with indices of SW. In contrast, perceptual-motor, short-term memory and standard language measures did not correlate with indices of SW. These results support the view that EEG SW may reflect processes essential to the successful management of working memory and other complex cognitive tasks. P2-28. On the Border between Consciousness and Unconscious Processing. Erik Olsson, Department of Philosophy, Go¨teborg University, Box 200, SE-405 30 Go¨teborg, Sweden. E-mail: [email protected]. Whether or not consciousness is a unity of components or only a heterogeneous concept there is a unity in phenomenal experience (PE), i.e., some events in the world feel and this contrasts to physical processes in general. However it is not clear whether it is possible to find a unity among the physical constituents of PE. One way of framing this question is whether PE requires full blown consciousness or if there could be unconscious creatures with rudimentary phenomenal experiences of for example pain. In the first case, the sufficient and possibly necessary physical conditions for PE could be complex constellations of processes. In the latter case there might be single sufficient and possibly necessary physical conditions. These are not the only difficulties with necessary and sufficient conditions for PE. If we search for a way to separate the constituents of PE from what is only coexistent with it, we have to deal with the possibility that a process can be both a constituent of PE in some cases and only coexistent in other cases. Such complications do not mean that we should resign in despair nor that we need another research paradigm. P2-29. Why Is a Compatibilistic Account of Qualia Both Necessary and Difficult? Giuseppe Varnier, Dipartimento di Filosofia e Scienze Sociali, Universita` di Siena, Via Roma 47 (Palazzo San Galgano), I-53100 Siena, Italy. E-mail: [email protected]. I offer a new taxonomy, that builds, and improves, on the conflicting taxonomies by M. Nelkin N. Block etc., and on some proposals on fine-grained distinctions in

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(linguistic) structure and elements of C(onsciousness) by H.-N. Castan˜eda and others. In particular, I show that indexical and quasi-indexical reference, being irreducible to proper names, descriptions etc., reveal experiential activity of the subject of (self-) attribution, and possibly point to innate mechanisms. I propose a fourfold taxonomy of interconnected, not excluding and not necessary nor sufficient features of C, distinguishing between intentionality (IN: both image-like and linguistic), phenomenality (P: qualia, both in a systematic and an occasional sense, and as both specific and abstract or generic qualities in thought or perception), introspection (IS: both implicit and explicit, and linguistic), and self-consciousness proper, understood as fully linguistic and subject-centered introspection, or theory of mind (ToM), in an intuitive sense (SC: both in a primitive and in a conceptualized sense). I also argue, conjecturally, that the so-called unity of C or better SC (but not C simple!) can be found, if at all, only in, or(self-)attributed only to/by, fully linguistic and social beings like humans, depending probably on specific neurophysiological wirings but also on an explicitly linguistic, even narrative, construct related to the second aspect of selfconsciousness (SCb). At the level of cultural artifacts, this unity is to be found in the indexical word I. In part 2, the bulk of the paper, I build on the taxonomy and on the latter conclusion to review the reasons leading (a) to assume that qualia exist and are not to be quined or reduced to the by-product of a stance, and (b) to think that they can be accounted for naturalistically, though not reductionistically. Beside some well-known arguments (inversion, absence, phenomenology and semantics of experience and indexicality, some consequences of rigidity) I discuss some more important ones for (a). The general argument is related to the fact that qualia pose a challenge to physicalism and functionalism, and that compatibilistic accounts are not yet convincing (Shoemaker, Sellars). A reason is seen in the confusion between C and SC, which I call Cartesian conflation, and in inadequate understanding of qualia.

P2-30. Implementation of the Spiking Neuron Stochastic Diffusion Network on Parallel Hardware. T. Morey, K. De-Meyer, S. J. Nasuto, & J. M. Bishop, Department of Cybernetics, University of Reading, Whiteknights, Reading, Berkshire, United Kingdom. E-mail: [email protected]. The Spiking Neuron Stochastic Diffusion Network, SNSDN, first reported at ASSC 2 [1], is a novel network that performs Spiking Neuron Stochastic Diffusion Search, SNSDS. SNSDS is a biologically plausible variation of Stochastic Diffusion Search, SDS, a non-deterministic search algorithm able to rapidly locate the best instantiation of a target pattern within a noisy search space [2]. The qualitative behaviour of SNSDN is discussed in [4]. This paper describes the implementation of synchronous SNSDN on a multiprocessor architecture. Emphasis is placed on the communication protocols required in order to prevent contention occurring between the parallel processing elements. Results obtained from large scale simulations of the parallel architecture are compared to those from a simple MATLAB simulation and to values predicted from SDS theory [3].

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REFERENCES 1. Bishop, J. M., & Nasuto, S. J. (1998). Neural stochastic diffusion search network—A theoretical solution to the binding problem. Proceedings of the ASSC2, Bremen. 2. Bishop, J. M. (1989). Stochastic searching networks. Proceedings of the 1st IEE Conference of the ANNs, London. 3. Nasuto, S. J. (1999). Resource Allocation Analysis of the Stochastic Diffusion Search, Ph.D. Thesis, University of Reading. 4. De Meyer, K, Bishop, J. M., & Nasuto, S. J. (1999) Attention through self-synchronisation in the spiking neuron stochastic diffusion network. Proceedings of the ASSC4, Brussels.

P2-31. The Role of Visual Experience in Senso-Motor Integration. Irina Blinnikova, Institute of Psychology, Russian Academy of Sciences, Yaroslavskaya, 13, Moscow, 129366, Russia. E-mail: [email protected]. The role of visual experience in senso-motor integration was studied by observation of behaviour and testing of 22 infants from 0 to 2 years with heavy visual impairments (acuity ranged from total blindness to 10% in the best eye). The results of poor vision infants were compared with the results of matched sample of normal vision infants. The study showed that visual experience plays the significant role in the process of senso-motor integration. In the tests where motor reactions were provoked by audio stimulus infants with impairments displayed much more lower results. They respond to stimulation by very weak motor reactions. The repetition of audio stimulation normally resulted in fade away of any reaction. Besides, visually impaired infants displayed very selective reaction to audio stimulus. A constant and normal reaction was demonstrated only to the very familiar stimulation. Unfamiliar and unpleasant sounds were ignored. Although, in the motor development tests not associated with audio stimulation, visually impaired infants displayed the same results as infants with normal vision. That is why we came to conclusion that early visual experience deficit results in the difficulties of sensor and motor binding. The full motor reaction appears only in respond to familiar, i.e., already represented in mind stimulus. (Supported by Russian Foundation of Humanitarian Research, Grant 98-06-08123.) P2-32. Is Awareness a Framework for High-Level Cerebral Functions? Franc¸ois Anceau, CNAM, Chaire TFI, 292 rue St. Martin, 75141 Paris Cedex 03, France. E-mail: [email protected]. We have developed a model for awareness in which the capability of focusing the attention seems to be the same mechanism as the one used for triggering the conscious mental functions. This mechanism makes conscious thinking an extension of the voluntary attention mechanism which was defined by A. H. Luria. We will call Attention Point the focusing point of the voluntary attention process. The moving of this point makes conscious thinking serial. When a conscious process is operating, this point triggers automatic functions by visiting successively their triggering areas in the mental space. We will suppose that the emergence of the awareness mechanism has risen from the basic attention mechanism through an increase of its triggering possibilities. This evolution process could give to the attention point the capacity to move outside

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the sensory areas, opening the possibility of paying attention to abstract notions. We propose that the awareness mechanism could be a framework providing facilities to make possible the very existence of the high-level non-conscious cerebral functions such as intelligence, long-term memory, reasoning, . . . One of the most important of these facilities would be to provide these mental functions with a certain coherence in time due to a kind of consistency mechanism. Thereby such a timing consistency could be the consequence of the seriality of the conscious activation of the automatic mental functions. P2-33. Memory Trace Separation in Dendrites. Bjørn Gilbert Nielsen, Bjørn Gilbert Nielsen, Brainscience Group, Physics Department, Technical University of Denmark, Anker Engelundsvej, DK-2800 Lyngby, Denmark. E-mail: [email protected]. Spatiotemporal sequences of patterns (such as behavioural programs) can be stored in simple recurrent artificial neural networks by using a Hebbian learning mechanism. Using the standard approach of storing the sequences as trajectories through statespace only permits the storage of one or very few sequences per network because novel sequences have a tendency to wash-out older items in memory simply because synapses are shared between patterns (the stability-plasticity dilemma). In this paper a method is proposed, by which it is possible to train an ordinary recurrent artificial neural network in a way that enables protected storage of multiple spatiotemporal sequences of patterns. The proposed method involves the usage of NMDA-receptor type synapses in combination with anisopotentiality between dendritic branches. NMDA receptors are voltage and transmitter dependent, so they can effectively be used to keep track of dendritic site activity. Subsets of synapses can be kept separated at differentially activated dendritic branches, especially if these branches are independently primed by means of a reference activity (which would function by pre-binding of glutamate). Each synaptic subset is a learning locus which can contain one sequence, so that as many sequences as there are reference afferents can be coded into the network. These learning loci can in principle have sizes ranging from the single spines on a dendrite, over small dendritic twigs, whole branches, and of course whole neurons (only whole branches and neurons are considered in this paper). This is a biologically plausible model which might give some insight into the workings of real nervous systems when encoding and retrieving behavioural motor programs. P2-34. Toward a Multi-Level Theory of Intentionality. David Rose, Department of Psychology, University of Surrey, Guildford, Surrey GU2 5XH, United Kingdom. E-mail: [email protected]. To define intentionality as a mark of the mental presupposes a two-level ontology. But there are numerous arguments for multi-levelism, such as the nested, hierarchical nature of biological systems and the rationale for homuncular, teleological functionalism. Yet how can intentionality fit into such a complex picture? A unified schema will be presented wherein an event is a co-occurrence of interactions happening simultaneously at many levels between the sub-systems (or modules) that form each level in a hierarchy of systems and sub-systems. Each such interaction consists at one and the same time of (i) intentional pointing, (ii) cause and effect, and (iii) the

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passage of information. Moreover, at every level, for every interaction, a form of intentionality supervenes, causation occurs and information passes. The distance over which each interaction operates increases with level: the higher the level of a system, the more remote the events pertained to, and thus the more ‘‘externalist’’ or broad the system’s content. The metaphysical bases of this theory will be discussed, and applied to neural examples such as the frog’s bug detector. P2-35. Consciousness and Consistency. Bruno Marchal, Universite Libre de Bruxelles, Avenue F. D. Roosevelt, 50, IRIDIA, CP 194/6, B-1050 Brussels, Belgium. Email: [email protected]. I propose an abstract theory of consciousness. The theory has its origin in Myhill computationalist approach to self-reproduction and life, and in abstract psychology, where essentially Go¨del’s incompleteness theorem is taken as the first theorem in exact psychology. That theorem, interpreted in term of machine’s psychology, says that it is impossible for any consistent machine with sufficient introspective power to prove its own consistency. Results in provability logic and theoretical machine learning show, nevertheless, that it is quite possible for such a machine to infer its consistency. No contradiction will occur as long as the machine makes the distinction between proof and inference. Inspired also by Helmholtz definition of perception as instinctive inferences, I propose to tackle the notion of consciousness by the procedure of automatic (pre-programmed) inference of self-consistency. I argue that such an approach makes it possible to explain (at best) and reformulate (at least) most of the traditional problems in the conceptual foundations of the cognitive science, but also in the conceptual foundation of physics. Results are: explanation of the elusiveness of consciousness, explanation of the unity and role of consciousness as a relative self-speeding up machinery, new formulation of the mind-body problem showing why and how the logic of the possible ‘‘physical’’ propositions can be derived directly from the machine’s psychology. P2-36. Possible Mechanisms behind Unity of Private Experience: Perspective from the Indian Philosophical Traditions. Navjyoti Singh, National Institute of Science Technology and Development Studies (NISTADS), K. S. Krishnan Road, New Delhi 110 012, India. E-mail: [email protected]. In the classical Indian philosophical traditions problem of the unity of consciousness has been addressed from two positions (1) ‘‘unity of ownership’’ theory (Nyaya), and (2) ‘‘unity of causal antecedents’’ theory (Buddhist). However, in understanding working of the mind, following methodological insights are common to various approaches: (1) (2) (3) (4)

Private experience can be decomposed into simple episodes; Each mental episode is temporally extended; Unit of temporal extension is irreducible ‘moment’; Typology of episodes disclose structure of mind, its type-elements and their relations;

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(5) Mental episodes are related to each other in a way that conserves phenomenal unity of mind; and (6) An integrative entity/structure called ‘‘manas’’ is conceived that links (a) sensa, (b) motor action, (c) internal states and causes mental episode. Methodologically Indian approaches are strictly internalist. Theoretic claims are based on formal features of episodes utterly independent of the content. Units of ‘moment’ help characterise and embed causal processes in ‘‘pure time axis’’ of mind, creating powerful tool for explaining mental change. It is ‘‘manas’’ that functionally constructs unity of experience. Two approaches of conceiving ‘‘manas,’’ namely, ‘‘ownership’’ and ‘‘antecedent’’ will be explored. Mechanism of ‘‘manas’’ derived from these approaches shall be presented so that their theoretical power and consistency can be related to current researches. P2-37. Weaker Gamma-Band-Synchronization as the Biological Basis of Cognitive Deviations in Schizophrenia. E. R. Straube & C. Nisch, Institut fu¨r Psychologie, Friedrich-Schiller-Universita¨t, Jena, Abteilung Klinische Diagnostik/Intervention & Klin. Psychologie, am Steiger 3/Hs.1, 07743 Jena, Germany. E-mail: [email protected]. Despite strong research efforts the psychobiological causes of schizophrenic disorders are not elucidated up to now. Although, the type of symptomatology as well as cognitive deviations point toward a basic and rather uniform disturbance of cognitive and behaviorally functions. The theories which exist momentary explain only parts of cognitive deviations. Moreover, results testing these theories are quite inconsistent. Furthermore, in most of the psychological theories a link to a underlying biological mechanism is lacking. This shows the need for a new theoretical approach. A large amount of studies were published the plast 5 to 10 years which examine the role of synchronized firing of cell assemblies in the gamma-frequency-range together with cognitive functioning in humans. Thirty-30 to 70 Hz- oscillations were shown to be connected to attention, memory, learning and priming, i.e., binding cognitive elements. In comparing the role of these functions in healthy people with the cognitive deviations of schizophrenics we developed the theory, that a weak synchronization (weak binding mechanism), is a good candidate to explain the neurocognitive problems of schizophrenics. Recently data were published, which confirm our theory. P2-38. Disorders of Consciousness: A New Look at Suffering. C. Richard Chapman & Yoshio Nakamura, Department of Anesthesiology, University of Washington, Seattle, Washington 98195-6540. E-mail: [email protected]. Medicine seeks to prevent or relieve suffering, but it has never formally recognized the concept. It lacks a meaningful definition and has no way to assess suffering in patients under its care. The emergence of the concept of the self in the multidisciplinary field of consciousness research suggests a way to introduce suffering into medicine. We propose that suffering occurs when a person afflicted with an illness experiences threat or damage to the ‘‘sense of self ’’–that is, his/her awareness of existing as an agent in the physical and social environment. The sense of self evolves con-

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stantly, but it is grounded in the person’s autobiographical narrative, and this generates a future trajectory. As post-modern theorists emphasize, the sense of self is complex and multi-focal for many people, and it depends heavily on a changing network of relationships and roles. The suffering construct is a natural extension of medicine’s Quality of Life. Assessing it requires evaluating a person’s normal sense of wellbeing and functioning and contrasting this with the person’s immediate sense of compromised well-being and functioning. The degree of discrepancy defines the amount of suffering. This approach can help medicine to design interventions for suffering and evaluate their efficacy.