Presaccadic Brain Potentials in Conditions of Covert Attention Orienting

Resumen

Twelve healthy subjects underwent investigation of averaged (electroencephalogram) EEG potentials during preparation for motor activity and in the latent period (LP) of visually evoked saccades by presentation of stimuli using Posner’s (1980) design of “cost-benefit.” It has been shown that covert spatial attention orientation leads to an increase in amplitude and decrease in latency of presaccadic initiation potential peaks within the saccadic latent period (LP) (P-100, N –50). Processes of covert orientation of attention during the interstimulus interval period of anticipation of the target stimulus correlate with the increase of slow negativity of fronto-parietal-temporal localization. Spatial-temporal changes of presaccadic potentials are evidence of the fact that orientation of attention during motor preparation and saccadic initiation is reflected in intensification of fronto-parietal networks of saccadic control and attention, activating the fronto-medio-thalamic and thalamo-parietal modulating systems.