[Analysis of current source density in the superior colliculi of cats in response to punctate visual stimulation]

The EPs in the cat superior colliculus to the punctiform light stimulation were of negative polarity and did not show the potential reversion. The region of EP recording was from 0.1 to 0.9 mm (stratum griseum superficiale). The field potential profile was subjected to the current source density analysis to determine the location and sequence of the current sources and sinks after punctiform light stimulation. The earliest current sink was observed at the depth 0.6--0.8 mm, the later and the most prominent local one--at 0.2--0.3 mm. The EPs to punctiform light stimuli seem to indicate more precisely the location of afferent synapses.