Convergence of Y and non-Y channels onto single neurons in the superior colliculi of the cat.
Receptive field properties of single neurons in the cat superior colliculus were examined following selective conduction-block of Y-type fibers in contralateral optic nerve. Although the responses evoked by photic stimuli presented via the Y-blocked eye were significantly weaker than those evoked by stimuli presented via the normal eye, > 85% of collicular cells were binocular. Furthermore, when binocular cells were stimulated via the Y-blocked eye their median upper cut-off velocity (100 degrees /s) was significantly lower than that (400 degrees /s) for stimuli presented via the normal eye. Thus, there is a substantial degree of excitatory convergence of Y- and non-Y- information channels on single collicular neurons and the responses to high velocity of motion appear to depend on the integrity of Y-type input.
Wang
C
C
Institute for Biomedical Research, University of Sydney, NSW 2006, Australia.
Waleszczyk
W J
WJ
Benedek
G
G
Burke
W
W
Dreher
B
B
D000200:Action Potentials / Q000502:physiology*; D000344:Afferent Pathways / Q000166:cytology / Q000502:physiology*; D000818:Animals; D002415:Cats; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009900:Optic Nerve / Q000166:cytology / Q000502:physiology*; D009949:Orientation / Q000502:physiology; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000502:physiology*; D013477:Superior Colliculi / Q000166:cytology / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology; D015348:Vision, Binocular / Q000502:physiology*