Journal of Neurophysiology, Vol 38, Issue 1 198-209, Copyright © 1975 by APS
An electrically evoked slow potential of the frog's retina. II. Identification with PII component of electroretinogram
R. W. Knighton
1. To show conclusively that the electrically evoked retinal response
(EERG) is in fact an electrically evoked component of the usual ERG, it is
necessary to show that the two responses have the same intraretinal pattern
of current generators. A method for determining when two responses have the
same origin has been developed. This method utilizes measurements from a
single microelectrode penetrating the retina. 2. The method was sensitive
enough to detect differences in the origins of two responses when they were
present. 3. The EERG had the same intraretinal origin as the PII component
of the ERG, and thus is the PII component evoked by electricity rather than
by light. 4. The hypothesis that electrical stimuli act on the synaptic
terminals of the photoreceptor cells predicts that electrical current will
evoke components of the ERG. The fact that the EERG is an electrically
evoked component of the ERG fulfills that prediction.
