Inferring perceptual states from fixational eye movements

titleInferring perceptual states from fixational eye movements
start_date2024/05/08
schedule13h-14h
onlineno
location_infoRoom 612 & on Zoom
summaryEven when we attempt to maintain steady fixation on an object, our eyes drift and we make small ballistic movements called microsaccades. Although we are seldom aware of these fixational eye movements, it is becoming increasingly clear that they can provide a window onto perceptual and cognitive processes occurring within the brain. In this talk I will describe two lines of research exploiting information contained in the timing of microsaccades to make inferences about individuals’ perceptual states. First, I will show that inhibition of microsaccades after the onset of transient visual stimuli is highly sensitive to stimulus visibility, providing the basis for an automated, objective method of measuring visual contrast sensitivity during passive viewing. Second, I will demonstrate that microsaccade rate can also be used to infer individuals’ expectations regarding the timing of future stimuli. Interestingly, these ‘oculomotor expectations’ can be dissociated from expectations inferred from Bayesian time perception paradigms, raising the possibility that multiple domain-specific forms of temporal expectation coexist in the human brain.
responsiblesSeghezzi