Adaptation in catfish retina.

K I Naka; R Y Chan; S Yasui

doi:10.1152/jn.1979.42.2.441

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Adaptation in catfish retina.

K I Naka·R Y Chan·S Yasui

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Abstract

1. We define absolute sensitivity as (voltage/illuminance) and incremental sensitivity as the peak-to-peak amplitude of the first-order (Wiener) kernels. 2. Incremental sensitivity of the horizontal cells is the local slopes of the Michaelis-Menten equation and that of more proximal neurons is the Fechner slope. In a log-log plot, the former has a slope of -2, whereas the latter a slope of -1, as predicted by Williams and Gale (39). 3. During a moderate to strong steady illumination, absolute sensitivity decreases but incremental sensitivity increases. The reverse occurs during dark adaptation. 4. The presence of a steady illumination did not prevent signal transmission from horizontal to ganglion cells. 5. From these results we conclude that: adaptation in the catfish retina includes two components: a) a lateral shift of the voltage-intensity curve along the intensity axis, and b) changes in the time course of light-evoked response. We argue that the latter phenomenon is related to the presumed horizontal cell-to-receptor cell negative feedback.

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Adaptation, Physiological Animals Dark Adaptation Electrophysiology Fishes Neurons Retina Vision, Ocular Journal Article Research Support, U.S. Gov't, P.H.S.

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K I Naka, R Y Chan, S Yasui. 1979. Adaptation in catfish retina.. https://doi.org/10.1152/jn.1979.42.2.441

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