Peri-saccadic visual sensitivity is higher in the upper visual field

Visual neural processing is distributed among a multitude of sensory and sensory-motor brain areas exhibiting varying degrees of functional specializations and spatial representational anisotropies. Such diversity raises the question of how perceptual performance is determined, at any one moment in time, during natural active visual behavior. Here, exploiting a known dichotomy between the primary visual cortex and superior colliculus in representing either the upper or lower visual field, we asked whether peri-saccadic visual sensitivity is dominated by one or the other spatial anisotropy. Humans detected peri-saccadic upper visual field stimuli significantly better than lower visual field stimuli, contrary to known perceptual superiority in the lower visual field during steady-state gaze fixation. Consistent with this, peri-saccadic superior colliculus visual responses were also significantly stronger in the upper visual field than in the lower visual field. Thus, peri-saccadic visual sensitivity reflects oculomotor, rather than visual, map spatial anisotropies.