GRASP Special Seminar – Avi Ziskind, Columbia University, “Neurons in Cat V1 cluster by degree of tuning but not by absolute spatial phase or temporal response phase”

Abstract: Nearby neurons in cat primary visual cortex (V1) have similar preferred
orientation, direction, and spatial frequency. How diverse is their
degree of tuning for these properties? Are they also clustered in their
tuning for the spatial phase of a flashed grating or the temporal phase
of a drifting grating? To address these questions, we used tetrode
recordings to simultaneously isolate multiple cells at single recording
sites and record their responses to gratings of multiple orientations,
spatial frequencies, and spatial/temporal phases. We found that
orientation tuning width, spatial frequency tuning width and direction
selectivity index all showed significant clustering. Tuning for the
spatial phase of a flashed grating stimulus (“absolute spatial phase”)
and temporal phase of a drifting grating stimulus (“temporal phase”)
however, showed no clustering.