The oscillations of biological systems: Methods and perspectives, part 2

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However, little is known about the factors involving asymmetric change in MMN peak latencies. Methods: Experiment 1 compared the stimuli conditions, which included a silence gap that replaced a tone segment that had decreased intensity (early filled and late filled). The combination of full stimulus and one of the four stimuli (i.e., early gap, late gap, early filled, and late filled) were presented in oddball sequence (85% vs. 15% and vice versa). As a result, the full stimulus duration rather than the gap duration per se was compressed in sensory memory, similar to the findings of Yabe et al. (2005). Experiment 2 varied sound intensity and showed that the saliency of the stimulus affects the peak latency of MMN. Experiment 3, which examined the effect of stimulus duration, demonstrated that both the temporal element and the saliency of the stimulus affect asymmetric change in MMN peak latencies. Conclusion: These findings suggest that the temporal element of a full auditory stimulus is compressed in neural representations and is influenced by the saliency of the stimulus. doi:10.1016/j.ijpsycho.2014.08.661

Functional relationships between mismatch negativity and early deviance-related effects Carles Esceraa, Maryam Aghamollaiea, Heike Althena, Tetsuya Shigaa,b, Katarzyna Zarnowieca, Sabine Grimma a Institute for Brain, Cognition and Behavior (IR3C), Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain b Department of Neuropsychiatry, Fukushima Medical University, Fukushima, Japan Sudden changes in the acoustic environment may convey critical survival information, and therefore the auditory system needs to implement automatic mechanisms to allow detection of these changes and draw attention accordingly. One such mechanism is based on the encoding of the auditory regularity in sensory memory neural traces, and the issuing of an attention call for focused attention. Such theoretical formulation is based on a brain response derived from the human EEG, namely the mismatch negativity (MMN) evoked potential, peaking at about 100–200 ms from the onset of an auditory event that deviates from the ongoing regularity. By its long latency and cerebral sources, the cortical nature of both the processes of regularity encoding and deviance detection were assumed. More recerently, both single-unit recordings in animals and the studies of the Middle Latency Response (MLR) and the Frequency Following Response (FFR) in humans have demonstrated that regularity encoding and deviance detection can take place at much earlier (circa 20–30 ms) and hierarchically lower (medial geniculate body, inferior colliculus) levels than those giving rise to the MMN. All these findings together support the view that deviance detection is a basic principle of the functional organization of the auditory system, from brainstem up to cortex. Yet, the functional relationships between regularity encoding and deviance detection at different levels of the auditory hierarchy is not fully understood. We will present two recent ongoing studies from our laboratory addressing this issue. In the first study, the MMN and the MLR deviance-related correlates were recorded in N = 30 healthy participants watching a silent video movie to an up-chirp (17 ms; 50– 8000 Hz) presented as deviant stimuli (p = 0,03 each) from loudspeakers located at 12, 24, 36 and 48° from a standard location at 0°. Reversed blocks were also implemented. All deviants elicited a clear MMN that increased linearly as a function of the location change. In the MLR latency range, preliminary results suggest effects of stimulus change for both Na and Pa components, yet with no further differences as a function of location magnitude. The second study aimed at comparing

deviance-related effects at cortical, i.e., MMN, and subcortical – as indexed by the complex Auditory Brainstem Response (cABR) – levels. Responses were recorded to an amplitude modulated tone (carrier frequency, 2230 Hz; modulating frequency for deviant, 410 Hz, for standard, 290 Hz) presented in oddball (p = 0.2) and reversed oddball conditions at a constant SOA of 363 ms. doi:10.1016/j.ijpsycho.2014.08.662

Temporal integration of auditory information as revealed by MMN and earlier evoked potential correlates: A preliminary study Tetsuya Shigaa,b, Miriam Cornellaa, Katarzina Zarnowieca, Shuntaro Itagakib, Michinari Nozakib, Satoko Asanob, Yusuke Osakabeb, Masayuki Hikitab, Hirooki Yabeb, Carles Esceraa a Institute for Brain, Cognition and Behavior (IR3C), Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Spain b Department of Neuropsychiatry, Fukushima Medical University, Japan Humans are exposed to enormous amounts of auditory inputs, so that the auditory system faces the challenge of editing it into meaningful chunks. This does not occur only in attentive situations, but is also implemented as an automatic discriminative process in the absence of attention. These mechanisms of auditory information clustering can be studied with the Mismatch Negativity (MMN), a negative component of the event-related brain potential (ERP). Auditory MMN is related to regularity encoding into auditory sensory memory, and elicited in response to any sound's change automatically, even in the absence of attention. That is to say, the MMN is generated as a result of discrepancy between a novel auditory event and the neural trace of the frequent stimuli stored in sensory memory. The typical latency of MMN is 100–200 ms after the onset of the deviant stimulus. A seminal study by Yabe et al. (1998) revealed that the auditory-cortex mechanism underlying sensory memory integrates acoustic events over time, producing a perception of a unitary auditory event. The length of this temporal window of integration (TWI) was estimated in 160–170 ms, as suggested by the emerging behavior of the MMN in an omission oddball study with stimuli presented at different stimulus-onset asynchronies. Recently, a series of studies have shown that regularity encoding and deviance detection can take place automatically in much earlier and hierarchically lower than those generating the MMN, giving rise to deviance-related correlates by the Middle-Latency Response (MLR) of the auditory evoked potential. The MLR is characterized by a sequence of waveforms in the range 12–50 ms, shown as N0, P0, Na, Pa, and Nb. The aim of the present study was to estimate the duration of the TWI by the generator mechanisms of the MLR as well as to compare it with that estimated from the MMN. Here, we introduce a series of studies about the TWI reflected by the MMN and the comparison with the MLR. doi:10.1016/j.ijpsycho.2014.08.663

Symposium B4 The oscillations of biological systems: Methods and perspectives, part 2 Organizers: Vilfredo De Pascalis (Italy) & Robert J. Barry (Australia) This part of the joint symposium with Prof. Danilova and colleagues illustrates the important role of brain oscillations in human functioning in a variety of experimental paradigms. It uses a range of methodologies, and discusses some of the issues and

International Journal of Psychophysiology 94 (2014) 120–261

problems in the field. De Pascalis and Scacchia begin with a study of induced neural oscillations in an examination of analgesic effects of placebo. They found different patterns of induced brain oscillations for individuals reporting increased/decreased pain perception with placebo, and also for individual differences in hypnotizability. Ciorciari used EEG oscillations and fMRI separately to explore neural networks associated with different thinking styles. His results jointly support different functional networks for individuals demonstrating different personality types, showing the fundamental importance of such neural networks in the study of individual differences. In a number of oscillation studies Barry and De Blasio have been exploring the preferential occurrence of particular EEG phases at stimulus onset in paradigms with fixed interstimulus intervals, and phase effects on stimulus processing and the associated ERPs. Here they discuss problems inherent in such assessments of EEG phase at stimulus onset, and propose a new approach to improve the validity of dynamic phase estimates. In a complementary approach to investigating the importance of EEG oscillations, De Blasio and Barry examine the impact of prestimulus oscillatory amplitudes on ERP components in a Go/NoGo task. They report trend analyses across 10 levels of prestimulus EEG amplitudes in the traditional delta, theta, alpha and beta bands, and illustrate the differential impact of EEG oscillations in the brain processing of stimulus events. We hope these four papers, together with those in Part 1 of the symposium, encourage a wider focus on the role of oscillatory activities in the organisation of all behaviour. doi:10.1016/j.ijpsycho.2014.08.664

Effects of placebo analgesia and hypnotizability on prepulse inhibition of the startle reflex: A study of induced neural oscillatory activity Vilfredo De Pascalis, Paolo Scacchia Department of Psychology, Sapienza University of Rome Understanding how pain relief is achieved during placebo analgesia could help develop improved treatments for clinical pain. Here, we tested how hypnotic susceptibility and individual differences in placebo pain reduction was associated with altered modulation of acoustic startle response (ASR) and induced oscillations in the conventional electroencephalographic (EEG) frequency bands. Placebo analgesia was produced by conditioning whereby the intensity of a painful cold glass was surreptitiously reduced after the administration of a sham analgesic cream. Participants were thirtyfive healthy women volunteers. We used a trial-by-trial waveletbased time–frequency analysis of the (EEG) signal to provide induced oscillations delta (1–4 Hz, 140–240 ms), theta (4.5–8 Hz, 96–168 ms), alpha (8.5–13 Hz, 84–140 ms), beta1 (14–20 Hz, 60– 96 ms), beta2 (21–35 Hz, 60–80 ms), and gamma (36–45 Hz, 60– 96 ms) time–frequency ranges. The experimental conditions included three treatments: (1) resting (Baseline); (2) tonic pain, produced by holding a painful cold glass (− 3 °C) with the right hand; (3) tonic pain as in (2), after administration of a sham cream. During each experimental condition, we measured the amplitude of the pulsealone auditory startle reflex (ASR) and its prepulse inhibition (PPI). Pain reduction during placebo analgesia was associated with hypnotic susceptibility. Latency of the ASR was shorter in high hypnotizable (HH) participants who reduced pain sensation. PPI level of theta oscillations at central and frontal sites were positively associated with pain reduction. Importantly, enhanced PPI of beta1, beta2, and gamma oscillations in the frontal lobe during placebo analgesia was positively associated with the interaction between hypnotic susceptibility and pain reduction level. These results provide a new description of the neurobiological basis of placebo

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analgesia, demonstrating specific patterns of induced cortical oscillations subserving pain perception and the individual differences in hypnotizability. doi:10.1016/j.ijpsycho.2014.08.665

Psychophysiological investigations of individual differences (personality orientations) using EEG & fMRI Joseph Ciorciaria, John Gountasb Brain & Psychological Sciences Research Centre, Swinburne University of Technology, Australia b Murdoch University, Australia a

Background: Previous studies have investigated the neural networks associated with personality orientations and introspection of self (Bjørnebekket al., 2013; Zhu et al. 2012). Introspection is a process of self-monitoring, consciously thinking of one's feelings and thoughts which reflect ones' personality. To explore this further, EEG and fMRI techniques were employed in two studies which investigated the psychophysiological correlates associated with personality and thinking styles using a personality orientations model based on the Jungian four personality functions; the Gountas Personality Orientation (GPO). The GPO measures the strength of each thinking style; Emotion (E), Material (M), Intuitive/Imaginative (I) and Logical (L). The EEG & fMRI studies examined functional distribution of networks and examined whether specific neural networks exist for each orientation. Method: In the EEG study, 43 participants (M = 30.8, SD = 11.9 years) were tested doing a language based decision task while recording from 64 scalp EEG electrodes. Eye movement and other artifacts were removed during post recording analysis. The EEG Alpha coherence was calculated for the epoch associated with decision making (rating). This study was extended by testing an additional 40 participants (M = 27.5 SD 7.6 years) using a fMRI block design protocol. Functional activities (BOLD Response) were correlated with a series of language based and introspection decision making tasks. Results: In support of the EEG coherence results, the neuroimaging data suggest that different decision neural networks exist and are associated with each thinking style and personality orientation during decision making tasks. Discussion/Conclusion: These data suggest a left hemisphere relationship for the M and L types and a right neural network relationship for E and I types. The implications associated with decision making and individual thinking styles will be discussed. doi:10.1016/j.ijpsycho.2014.08.666

Problems in estimating oscillatory phase of the EEG at stimulus onset Robert J. Barry, Frances M. De Blasio University of Wollongong, Australia The perception, cognition, and behavioural outcomes associated with a particular stimulus depend on the EEG state of the brain at stimulus onset. These effects have been considered in relation to the amplitude and phase of particular EEG frequencies or frequency bands. Originally, these were estimated using filtering (first analog, and then digital) to select a narrower (e.g., 1 Hz wide) or broader (e.g., 8–13 Hz alpha) frequency band. It has long been known that such filtering “smears” the amplitude data of each frequency over time, but the impact of this is often ignored. In essence, around the time of stimulus onset, the filtered output contains information from both prestimulus