Аннотация:Saccadic eye movements as a simple motor act is informative model for studying neurophysiological mechanisms of executive control, including attention, decision-making and inhibition processes. In order to study EEG correlates of cognitive control of saccadic preparation and inhibition the "Go / no go" paradigm was used.
The parameters and topography of P1, P2 and P3 ERP components was shown to depend on the stimuli signal meaning and saccadic latency (LP). All subjects were divided into two groups: "slow" subjects with LP=277 ± 11ms and "fast" subjects with LP=193 ± 10ms.
The Go-P2 component in the “fast” group and the Go-P3 component in the “slow” one, coinciding with the saccade onset and spike potential, may reflect the processes of initiation and backward afferentation.
Our data allow us to suggest that Go-P1 in "fast" group and Go-P2 in "slow" one may be a marker of decision-making stage of saccade programming. They located in the 120-60 ms interval before the saccade onset and coincided with premotor component P – (minus) 100, which is associated with motor preparing and decision making. The parameters and topography of Go-P1 in "fast" group and Go-P2 in "slow" one indicate the inclusion of attention at the stage of decision-making. The Go-P100 in "slow" subjects may reflect the stage of stimulus analysis and evaluation, preceding the decision-making. The Go-P3 in “fast” group may reflect the processes of behavior monitoring and information transfer into working memory.
Regardless of subject groups Nogo-P2 amplitude was increased compared with Nogo-P1. We supposed that Nogo-P2 also reflects the decision-making stage. The meaning of decision (Go or No go) may be reflected in various patterns of the space-time dynamics of its focuses along the fronto-parietal networks of saccadic control: "top-down" in "Go" conditions and "bottom-up" in "No go" conditions.
The Nogo-P100 may reflect the stage of analysis and evaluation inhibitory stimulus. The focuses of Nogo P3 prevailed in the front-central zones in the "fast" subjects and in the parieto-occipital zones in the "slow" subjects, which may reflect a greater level of of the prefrontal cortex activation necessary for monitoring behavior and translating information into working memory.
The obtained data suggest various mechanisms of cognitive regulation in the preparation and inhibition of saccadic responses in "fast" and "slow" subjects, which are associated with different levels of cortex activation and spatial organization "patterns" of the fronto-parietal networks of attention, inhibition and saccadic control. (supported by RFBR, project 16-004-01079).