Interactions within the Spatially-distributed Cortical Neural Network during Visual Attentional Tasks

摘要

Many physiological experiments demonstrate that a cognitive performance during sustained attention tasks is not maintained at a constant level. Such behavioral lowfrequency variations are connected with dynamics of attentionrelated cortical neuronal networks. At the same time neurophysiological reason of a such behavior remains unclear. In this talk we analyze the neuronal interactions in alpha and beta bands by means of 31-channels EEG processing. As a visual attention task we use a binary classification of a large number of presented images – ambiguous Necker cubes. Analyzing of response time of subjects indicates that processing of similar tasks takes both long and short reaction time. Provided analysis based on complex network theory reveals strong correlation between response time and duration of formation of a functional frontoparietal functional network associated with perceptual decision-making process. Having considered a functional topology during a prestimulus period, we find that lower reaction times are subserved by a strong prestimulus functional connectivity over a somatosensory and sensorimotor areas of cortex. Finally, we show that high reaction times are dominant during the beginning of experiment and suppose that this time is required for a prestimulus template formation. Since similar visual tasks are presented several times during the experiment, brain uses their templates to perform them faster and effectively.