Movement perception, directionally selective ganglion cell responses and the involuntary eye movements. Neurophysiology at the level of information processing.

Two neural circuits in the retina are described, that involve neural interaction generated by image movement. One circuit increases the sensitivity in detecting movement in the visual field while the other circuit generates ganglion cell signals when an image moves in one preferred direction but not when moves in the opposite direction, explaining the observation of directionally selective ganglion cell responses described by Barlow and Hill (1963). In agreement with the recorded potentials, the circuit generates ganglion cell responses also when the light stimulus is stationary. This ambiguity in ganglion cell signals to the visual center limits the signals usefulness to images that are in constant movement. The only known such movement is that caused by the involuntary eye movements. The function of the circuit is therefore to stabilize the retinal image when transmitted to the visual center.