Scope of research of the Cognitive Psychophysiology Laboratory

Presentation on main research topics 2018

Brain mechanisms of cognitive control and attention

Making correct decisions in cognitive tasks critically depends on a number of brain systems supporting such functions as sustained attention, retention and activation of stimulus-response mappings, and inhibition of irrelevant motor responses. Cognitive control is a set of neural processes that keep the activity of these systems at an optimal level and coordinates them. Currently we are addressing the most intriguing issue in this field:   uncertain decisions, involving “ambiguity” and “changing one’s mind” in the process of response initiation. We believe that some degree of uncertainty is quite often involved in real-life decision making. This happens even when the task rules are simple and clear – partly because we are physically unable to keep our attention on everything we need, and thus we may miss some of the relevant information. We also study post-error adaptations – the way the brain reorganizes itself after erroneous responses, as well as we study or plan to study various aspects of reinforcement and conscious awareness in the framework of cognitive control.

For the current research, we use behavioral tasks that allow studying multiple aspects of cognitive control – with special emphasis on attentional mechanisms. We record EEG and use time-frequency analyses aiming at frontal midline theta rhythm, parietal occipital alpha rhythm, prefrontal beta rhythm and sensory-motor mu rhythm; we also use traditional event-related potentials such as P2, N2, P300, ERN, FRN, etc.

Brain activity during lexical semantics acquisition on the example of action words (in cooperation with MEG-centre headed by prof. T.A. Stroganova)

The nature of meaning assigned to words poses challenging questions to philosophy, psychology and neuroscience. Recent psychophysiological and behavioral studies have shown that classical understanding of brain mechanisms involved in language comprehension need to be revised in several important aspects, and have brought new intriguing insights to our understanding of subconscious underpinnings of word learning. Word meaning is represented by numerous distributed brain areas responsible for corresponding representations of sensory and motor experience – in line with the modern concept of "embodied", or "grounded" cognition.

This project aims at understanding the brain mechanism responsible for acquisition of word meaning by way of magnetoencephalographic recording throughout of the process of rapid associative learning. The behavioral task imitates natural word meaning acquisition through trial-and-error learning. The data processing involves a vast array of modern methods of MEG data analysis.

Brain mechanisms of intra-modal and inter-modal feature binding

Feature binding, or feature integration, is an important part of human perception. Gestalt perception allows us to sense real multi-dimensional objects instead of just seeing meaningless color and shape, hearing abstract pitch and timber. Despite the enormous importance of this process, we still know remarkably little about its inner mechanisms. Notably, it remains unclear whether feature bindingis automatic or requires attention. The purpose of this project is a comprehensive study of intra-modal and inter-modal feature binding process under different levels of attention involved.

To implement the research we use the condensation task, and we record both behavioral measures and evoked potentials (MMN and P300). We put forward the hypothesis that the critical processes in the brain, carrying the feature binding, occur relatively fast at the stage of automatic processing of information – i.e. at the preattentional level and do not require attention for their implementation. Yet the secondary level of binding occurs at higher levels, that indeed requires attention. A two-level understanding of binding allows resolving the long-standing argument concerning the mechanisms of feature binding.