Abstract
Our perception of the auditory and visual stimuli in the world remains stable despite frequent head and eye movements. For visual stimuli, this stability is achieved through the correction (remapping) of the object’s visual representation in retinotopically organized visual and oculomotor maps. In the present study, we use saccade curvature to investigate the competition between visual saccade targets and different multi-sensory distractors. We report clear physiological evidence for the existence of a supra-modal map of locations across saccades. In a double-step saccade task (consisting of a horizontal and then a vertical saccade made in sequence), we measured the curvature of the second vertical saccade in response to the brief presentation of a visual, auditory, or audio-visual distractor either before or after the initiation of the first horizontal saccade. We found that the second vertical saccade systematically deviated away from the distractor irrespective of its modality, showing that both visual and auditory signals compete with the saccade target representation within an oculomotor map (e.g. SC). More specifically, we found that vertical saccades deviated away from the memorized location of the distractors in space (not on the retina), which passed from one visual hemifield to the other across the horizontal saccade. Taken together these results point toward the existence of a common map of target positions independent of sensory modalities, involved in the trans-saccadic tracking of locations in space.
Meeting abstract presented at VSS 2015