Corticofugal influence on evoked activity of lateral geniculate neurons in the rabbit.
Corticofugal influence upon lateral geniculate units was evaluated by inactivating the visual cortex with a topical application of 3M KCL in rabbits. The results revealed a decrease of spontaneous firing in slow P cells following cortical depression suggesting a tonic corticofugal influence. The most consistently observed alteration was an enhancement of the ON response with a decrease of the response to the opposite stimulus (OFF); and vice versa: the short latency excitation being augmented. It is suggested that the visual cortex exerts a powerful influence on intra-geniculate inhibitory processes.
D000818:Animals; D013181:Cortical Spreading Depression; D004594:Electrophysiology; D005071:Evoked Potentials; D005829:Geniculate Bodies / Q000502:physiology*; D007395:Interneurons / Q000502:physiology; D009039:Motion Perception / Q000502:physiology; D009474:Neurons / Q000502:physiology; D010775:Photic Stimulation; D011817:Rabbits; D011930:Reaction Time; D013997:Time Factors; D014793:Visual Cortex / Q000502:physiology