Microsaccade-related brain potentials signal the focus of visuospatial attention

摘要: Abstract Covert shifts of visuospatial attention are traditionally assumed to occur in the absence oculomotor behavior. In contrast, recent behavioral studies have linked attentional cueing effects occurrence microsaccades, small eye movements executed involuntarily during attempted fixation. Here we used a new type electrophysiological marker explore attention–microsaccade relationship, visual brain activity evoked by microsaccade itself. By shifting retinal image, microsaccades frequently elicit neural responses throughout pathway, scalp-recordable human EEG as microsaccade-related potential (mSRP). Although mSRPs contain similar signal components (P1/N1) traditional visually-evoked potentials (VEPs), it is unknown whether they also influenced cognition. Based on established findings that VEPs amplified for inputs at currently attended locations, expected selective gain-modulation mSRPs. Eye and were coregistered classic spatial task with an endogenous cue. Replicating findings, direction early 200–400 ms after cue onset was biased towards cued side. However, cue-target interval, systematically enhanced occipital scalp sites contralateral hemifield. This effect resembled control condition did not interact underlying microsaccade, suggesting reflect focus sustained attention, which remains fixed location, despite microsaccades. Microsaccades merely artifact source EEG; instead, followed cognitively modulated can serve non-intrusive probes attention.