Eye movements create an ever-changing image of the world on the retina. In particular, frequent saccades call for a compensatory mechanism to transform the changing visual information into a stable percept. To this end, the brain presumably uses internal copies of motor commands. Electrophysiological recordings of visual neurons in the primate lateral intraparietal cortex, the frontal eye fields, and the superior colliculus suggest that the receptive fields (RFs) of special neurons shift towards their post-saccadic positions before the onset of a saccade. However, the perceptual consequences of these shifts remain controversial. We wanted to test in humans whether a remapping of motion adaptation occurs in visual perception.The motion aftereffect (MAE) occurs after viewing of a moving stimulus as an apparent movement to the opposite direction. We designed a saccade paradigm suitable for revealing pre-saccadic remapping of the MAE. Indeed, a transfer of motion adaptation from pre-saccadic to post-saccadic position could be observed when subjects prepared saccades. In the remapping condition, the strength of the MAE was comparable to the effect measured in a control condition (33±7% vs. 27±4%). Contrary, after a saccade or without saccade planning, the MAE was weak or absent when adaptation and teststimulus were located at different retinal locations, i.e. the effect wasclearly retinotopic.Regarding visual cognition, our study reveals for the first time predictiveremapping of the MAE but no spatiotopic transfer across saccades. Since thecortical sites involved in motion adaptation in primates are most likely theprimary visual cortex and the middle temporal area (MT/V5) corresponding tohuman MT, our results suggest that pre-saccadic remapping extends to theseareas, which have been associated with strict retinotopy and therefore withclassical RF organization. The pre-saccadic transfer of visual featuresdemonstrated here may be a crucial determinant for a stable percept despitesaccades.
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