Is consciousness necessary for cognitive control?

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(VMR). Also, the meaning-life orientations of adolescents were investigated by the adapted version (Leontyev, 2006) of the Purposein-Life Test by Crumbaugh and Maholick (1968, 1981). The obtained data were processed statistically. The data revealed that both boys and girls of the experimental group had lower indices of meaning-of-life orientations on all scales, as compared to teenagers of the control group (р < 0.01–0.05). The dissatisfaction with their past lives, low intelligence (understanding) of their lives in present time, absence of purpose in the future, and selective perception of their lives as a whole are the typical features of minor criminals. In a similar case, personal sense of the individual is deprivation of orientation and time perspective. In addition, the examinees of the given group show disbelief in their ability to control events of their own lives, fatalism and conviction that human life is not subject to conscious control and that the freedom of choice is illusory. The analysis of the indicators of simple VMR showed pronounced differences between minor offenders and the teenagers in the control group. These differences consist of a number of preemptive (warning) reactions and in total number of errors (р < 0.01) on visual stimulus, thus pointing at the predominance of the excitation processes over the inhibition processes. Much more significant differences were uncovered for offending boys and girls according to the indices of complicated VMR. These include the disturbance of the process of differential inhibition and decrease of its speed and an authentically significant decrease of the integrated indicator of reliability CNS (р < 0.001). In summary, it must be said that the prevalence of processes of excitation in the central nervous system, the decrease of ability to differentially inhibit, and the lability of the CNS appreciably determine meaning-life orientations and a predisposition to delinquent behavior. These can be prognostic markers for the formation of deviant behavior. Work is supported by the grant of the RHSF No. 07-06-18013е.

GI = 79, GL = 59) food compared to an identical, low GI (MLGI, GI = 51, GL = 38) meal, given 3 h prior to habitual bedtime, on the improvement of sleep quality in participants meeting research diagnostic criteria for sleep initiation insomnia. Four men and four women (n = 8) were randomized to the MHGI or MLGI meal for 2 consecutive nights. Ratings for meal palatability, satiety, and subjective and objective sleep measures, as well as postprandial glucose, insulin, plasma TRP/LNAA, and platelet poor plasma 5HT were measured. Meal palatability was similar for both meals indicating a good taste. Satiety was maintained until bedtime after both meals, however sex differences were present; satiety in men and women was similar after the MHGI meal, whereas after the MLGI meal, satiety in men was lower than in women. The average meal energetic load (kJ/kg) was greater for women (33.0 ± 4.1) than men (25.4 ± 3.8). Participants reported feeling more rested after the MHGI compared to the MLGI meal; ratings were higher in women than in men. There were no meal differences in objective sleep variables; however, objective SOL was lower than subjective SOL in all cases. In addition, there was a tendency in men to have more light sleep after MLGI compared to MHGI, but no differences were observed in women. With respect to biochemical measures, postprandial glucose was larger after the MHGI meal, but there was no difference in insulin response. There was a significant postprandial rise in plasma TRP/ LNAA; the peak percentage rise from baseline after the MHGI meal (17%) was substantially, but not statistically, different than the MLGI (8%) meal. Postprandial 5HT was unaltered. These results indicate that subjective sleep quality is improved after the MHGI meal and that improvements were greater in women than in men. Thus, this study demonstrates that foods with higher GL will yield a higher availability of tryptophan to the brain, and therefore may be useful to assist with symptoms of sleep initiation insomnia. Reference Afaghi, A., O'Connor, H., Chow, C.M., 2007. High-glycemic-index carbohydrate meals shorten sleep onset. Am J Clin Nutr 85, 426–430.

References Leontyev, D., 2006. (Леонтьев Д.А.) Test of the Purpose-in-Life orientations (PLO), 2nd edition. Smysl, Moscow. (18 pp). Crumbaugh, J.S., 1968. Cross-validation of Purpose-in-Life Test based on Frankl's concept. J. of Individual Psychology 24, 74–81. Crumbaugh, J.S., Maholick, L.T., 1981. Manual of Instructions for the Purpose in Life Test. Munster, Indiana.

doi:10.1016/j.ijpsycho.2010.06.168

Influence of the glycemic load (GL) on subjective and objective measures of sleep quality in sleep initiation insomnia Christopher P. Herrera, Patricia Ruell, Helen O'Connor, Chin Moi Chow Discipline of Exercise and Sport Science, The University of Sydney, Australia Insomnia is a symptom that limits sleep quality and is characterized by difficulty initiating and/or maintaining sleep. High glycemic index (GI) carbohydrate foods increase the ratio of tryptophan relative to other large neutral amino acids (TRP/LNAA). An elevated TRP/LNAA increases the availability of TRP to the brain, where it is readily converted into serotonin (5HT), a neurotransmitter involved in the regulation of satiety and sleep. In healthy sleepers, a high GI carbohydrate meal (GI = 109; ∼ 3200 kJ) shortened sleep onset latency (SOL), as compared to an identical low GI (50) meal (Afaghi et al., 2007). This high GI meal of Afaghi et al. was also considerably high in glycemic load (GL) and therefore is considered undesirable for regular use. This study evaluates the efficacy of mixed macronutrient (66.5% carbohydrate, 17% protein, 16.5% fat; ∼ 1915 kJ), high GI (MHGI,

doi:10.1016/j.ijpsycho.2010.06.169

Is consciousness necessary for cognitive control? Eva Van den Busschea, Gethin Hughesb, Florian Waszakb, Wim Geversc, Bert Reynvoetd a Faculty of Psychology, Vrije Universiteit Brussel, Belgium b Laboratoire Psychologie de la Perception, Université Paris Descartes, France c Unité de recherche en Neurosciences Cognitives, Université Libre de Bruxelles, Belgium d Faculty of Psychology, University of Leuven, Belgium The existence of unconscious perception is largely acknowledged. However, the limits and possibilities of unconscious processing remain unclear. For example, can unconscious stimuli induce cognitive control? To examine this, we varied whether an incongruent trial can produce interference at both the response and semantic level (difficult trials) or only at the semantic level (easy trials). Using this method in a Stroop context, Milham et al. (2001) found a general strategic slowing of RTs (i.e. the slowing of RTs generalized to neutral trials) in the difficult block, compared to the easy block. Our aim was to examine whether this general slowing, suggesting induced cognitive control, can also be found for unconsciously presented stimuli. In the first behavioral study, we used a masked priming paradigm in order to achieve this. Stimuli could either be presented clearly visible (conscious) or masked (unconscious). In a second study, we

Abstracts / International Journal of Psychophysiology 77 (2010) 288–342

aimed to shed further light on the behavioral results for unconscious stimuli using EEG. The behavioral results revealed a clear general response slowing for difficult trials, compared to easy ones, in the conscious condition and a trend of this general slowing in the unconscious condition. More importantly, we observed trial-by-trial adaptation effects: the general strategic slowing for difficult compared to easy trials was only observed when a conflict (i.e. incongruent trial) was present on the previous trial. This trial-by-trial adaptation was significant and highly similar for both conscious and unconscious trials. The EEG results for the unconscious condition were less clear. Our behavioral data indicate that unconscious stimuli do possess the ability, similar to conscious stimuli, to induce cognitive control in a very flexible, trial-by-trial way.

doi:10.1016/j.ijpsycho.2010.06.170

The relationship between trait anxiety and attentional bias in archers—An ERP study I-Fu Lunga, Lan-Ya Chuangb, Tsung-Min Hunga National Taiwan Normal University, Department of Physical Education, Taipei, Taiwan b Taipei Physical Education College, Taipei, Taiwan

a

Mounting evidence suggests the existence of a processing bias in favor of threat-related stimulation in anxious individuals. However, behavioral measures only provide an indirect measure of attentional processing, and moreover, can be confounded by postperceptual processes (e.g. decision making, motor responses). Therefore, the aim of the present study was to investigate attentional bias toward archery-relevant cues and underlying mechanisms by taking a sample of experienced archers and comparing the latency and amplitude of different ERP components between relatively higher and lower trait-anxious (TA) archers. Nineteen undergraduate archers with a mean age of 19.79 years (SD = 1.08) were administered the trait section of the STAI (State Trait Anxiety Inventory) one month before the experiment. The assessment task, dot-probe, consisted of four blocks, each of which contained 24 trials. Attentional bias score (ABS) was computed based on reaction time to probes. Behavior data was subjected to a one-way ANOVA to further understand the attentional preference in archers. ERP data were subjected to 2 (TA; high, low) × 2 (cue: positive, threatening) × 6 (electrode) mixed design ANOVAs and all variables were within-subjects except for state-trait anxiety level. The results showed that there was no difference in ABS between high and low TA archers, though low TA participants generated larger N1 amplitude toward positive cues over Fz and Cz electrode sites. Additionally, in contrast to low TA participants, high TA participants displayed faster N2 and P1 latency toward threatening cues. Low TA participants displayed faster P1 latency toward positive cues compared with high TA participants. Though it is difficult to discover different attentional preferences via ABS between low and high state-trait anxious archers, based on ERP data, it seems that high TA archers can rapidly detect threatening cues compared with low TA ones. Low state-trait anxious participants displayed different N1 amplitude across different electrodes, which may result from the influences of positive cues that elicit personal emotional experiences, and are then reflected by psychophysiological indexes.

doi:10.1016/j.ijpsycho.2010.06.171

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Visual attention ‘spills’ from targets to distractors under low perceptual load: An oculomotor investigation of the perceptual load model Hannah L. Pincham, Denes Szucs University of Cambridge, Centre for Neuroscience in Education, Cambridge, United Kingdom The perceptual load model of selective attention proposes that late-selection occurs in low perceptual load environments where spare attentional resources ‘spill’ over to process distractor stimuli (Lavie and Tsal, 1994). Conversely, under high load, capacity limitations mean that distractors are merely processed to an early, perceptual level. This means that distractor stimuli are most detrimental in situations where perceptual load is low, and one's attentional resources are not strained. Despite the perceptual load model's potential value in applied distraction research, previous investigations have employed artificial viewing conditions that prohibit naturalistic eye movements. The failure to measure eye movements is problematic because this psychophysiological technique will likely provide useful information about the relationship between perceptual load and attention. Given the documented link between fixation position and attention, we hypothesized that attentional ‘spilling’ should be apparent in participants' oculomotor responses. Sixteen participants were required to detect pre-defined targets in visual-search arrays. The perceptual load of the displays was manipulated by varying the number of distinct stimuli in the visualsearch displays. Distractors were either incongruent with the target stimulus, or neutral items. Participants' eye movements were recorded using a non-invasive infrared eye-tracking monitor. As expected, reaction times (RTs), initial saccade latencies and number of fixations were all found to increase with load. Although the distractor stimuli clearly interfered with RTs, this interference was not confined to low load trials, but persisted across loads. Therefore, the behavioural data was unable to support the perceptual load model. Importantly, however, a larger proportion of low load trials contained distractor fixations than did high load trials. That is, distractors were more likely to be fixated under low perceptual load. This study is the first to reveal that attention – as assessed through fixation position – literally spills from targets to distractors when one's perceptual resources are not taxed. References http://www.psychol.ucl.ac.uk/attention.lab/reprints/Lavie perceptual load selective attn JEPHPP95.pdf. Lavie, N., Tsal, Y., 1994. Perceptual load as a major determinant of the locus of selection in visual attention. Perception & Psychophysics 56, 183–197.

doi:10.1016/j.ijpsycho.2010.06.172

Phase shift effect on dichotic paradigm Murat Ozgoren, Onur Bayazit, Adile Oniz Dokuz Eylul University, Faculty of Medicine, Department of Biophysics, Izmir, Turkey The human brain has some lateralized function (1–2). A number of researchers have emphasized the brain laterality with behavioral data (1–3) using the dichotic listening paradigm (DL). In DL, semantically meaningless consonant–vowel (CV) syllables are presented to the participants (/ga/, /ba/, /ka/, /da/, /ta/, /pa/). Most of these syllables are matched as heteronymous (i.e. L-/ba/; R-/ga/). In DL, the subjects mostly hear the syllables that are presented to the right ear which is defined as ear advantage (EA).