Lateral geniculate cells of different channels of the rat's visual pathway: response changes and functional plasticity.

Potentials of single cells of the dorsal lateral geniculate nucleus (dLGN) were recorded extracellularly in albino rats by means of micropipettes filled with trypan blue for iontophoretic marking of tip localization. The cells were grouped concerning their response latencies to photic stimuli, their response patterns, and their localization within the dLGN. It could be shown in a conditioning paradigm that combination of light with electrical tail stimulation resulted in temporary response changes of "fast" OFF-cells which are mainly localized in the rostroventromedial part of dLGN. "Fast" ON-cells had mainly stable response patterns to light. Changes which persisted after the end of tail stimulation trials occurred in "slow" oN- and oFF-cells located in the dorsolateral and caudal part of dLGN.