Abstract
Background extracellular spike activity of single ganglion cells was recorded from axon terminals in the optic tectum of living immobilized fish. The sizes of the receptive fields of ON and OFF units with sustained responses (USR) amounted to 4–5° and were comparable with those of feature detectors. Generation of spike discharges by USR required contrast between the center and periphery of the receptive field. When there was no contrast, no spike activity appeared. The magnitude of the reaction was monotonically dependent on the level of this contrast. USR of both the ON and OFF types were connected with three types of cone (L, M, S). Both the center and periphery of the receptive field displayed color opponency, the center and periphery of the receptive field being opponent in terms of this characteristic. In other words, USR were double opponent and may thus take part in color discrimination. The simultaneous operation of feature detectors and ganglion cells with baseline activity separated into ON and OFF channels is represented retinotopically and may provide tectum opticum neurons with the visual scene information required for their function of controlling external attention.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.