How presaccadic gratings modify postsaccadic modulation transfer function

Threshold modulations for sinusoidal gratings tachistoscopically presented on the fovea after a saccade were determined as a function of the spatial frequency of a peripheral grating at the saccade goal and compared with thresholds of the "resting eye" condition. The results show a clear enhancement for medium spatial frequency gratings (3.2 c/deg) with peripheral gratings of the same spatial frequency. Therefore an information transfer from periphery to centre induced by saccadic eye movements is suggested. Suppression of low spatial frequency gratings (0.5 c/deg) is found to be independent from additional peripheral gratings and interpreted as an effect of a central inhibitory process elicited by the saccadic motor command. Some aspects concerning saccadic suppression, refixation, and visual stability are considered.