Higher upper visual field peri-saccadic sensitivity in SC neurons. A, Distribution of RF hotspot locations from our recorded population, expressed as a direction from the horizontal meridian. Approximately half of the neurons had RF hotspots in the upper visual field (yellow), and the rest had hotspots in the lower visual field. B, We assessed peri-saccadic suppression by evaluating visual sensitivity for stimuli appearing near the time of microsaccades (Hafed and Krauzlis, 2010; Chen and Hafed, 2017). Here, we characterized the microsaccade amplitudes for the two groups of sessions that we compared (in which we recorded either upper or lower visual field SC neurons). The eye movement amplitudes were matched across the two groups. C, Example upper visual field SC neuron responding to the onset of a low spatial frequency gabor grating (0.56 cpd). The saturated yellow curve shows the neuron’s visual response in the absence of nearby microsaccades (Materials and Methods), and the darker curve shows the same neuron’s visual response when the stimulus appeared immediately in the wake of microsaccades (individual microsaccade onset times are shown as a trial raster of red crosses in the background of the figure). The inset shows the RF location of this neuron, indicating that it preferentially represented a part of the upper visual field. Error bars denote 95% confidence intervals. D, Similar to C but for a neuron preferring the lower visual field (see RF map in the inset). Not only did the neuron have lower baseline visual firing rate (saturated blue curve; Hafed and Chen, 2016), but its suppressed visual response (darker curve) was also more strongly reduced than in the neuron in C. Thus, SC visual burst strength was still higher in the upper visual field for peri-saccadic stimuli.