Relation between Ganglion Cell Activity and the Local Electroretinogram of Cat Retina

Abstract

DELAY in the decay of the late receptor potential (late RP) of monkey retina has been demonstrated accompanying a progressive increase in the intensity of a 20 μsec flash¹. This delayed decay of the late receptor potential is accompanied, in the same retina, by a delayed decay of the d.c. component of the local electroretinogram². The d.c. component is thought to originate in the inner nuclear layer, and the late receptor potential in the receptor layer^1,3, and so the authors suggest that “the late receptor potential of the receptors is a crucial event which controls the activity of cells of the inner nuclear layer”. They indicate further than other off-responses of the visual system might be similarly related to the late receptor potential if they could be delayed by increases of stimulus intensity. With this in mind, I observed a relevant effect of stimulus intensity on the discharge pattern of cat ganglion cells. The on-response, at high intensities, continued into the off-period instead of terminating at the “off” of the flash. In addition, this ganglion cell effect seemed to be related to the behaviour of the d.c. component of the local electroretinogram.