Visual sensitivity in the upper and lower visual fields
Together with Dr Fracasso and Prof Hafed, we published a new article demonstrating that “Peri-saccadic visual sensitivity is higher in the upper visual field“.
Human participants involved in a perceptual discrimination task showed different level of saccadic suppression depending on the location of the stimulus in the visual field. Stimuli presented in the upper visual field were in fact less inhibited than stimuli presented in the lower visual field, suggesting a stronger sensitivity in the upper visual field.
While this results is at odds with the anisotropy recorded in the early visual cortex (e.g. V1), it reminded us of the differences for visual responses recorded in the superior colliculus. In this oculomotor structure, stimuli presented in the upper visual field showed sharper, stronger and faster visual field representations (Hafed & Chen, 2016). We then analyzed superior collicus data and we found that visual responses in during the peri-saccadic period were in fact stronger in the upper visual field, supporting the behavioral data.
Taken together, our result suggest the notion that peri-saccadic visual sensitivity reflects oculomotor, rather than visual, map spatial anisotropies.