Absolute and relative sensitivity of the scotopic system of rat: electroretinography and behavior

The goal of the present study was to relate the dark and light-adapted flash sensitivity of the scotopic threshold response (STR) and rod b-wave of the electroretinogram (ERG) to behaviorally measured rod increment threshold responses. Small amplitudes of the dark-adapted STR and b-wave, the latter...

Full description

Saved in:

Bibliographic Details
Published in:	Visual neuroscience Vol. 18; no. 4; p. 641
Main Authors:	Naarendorp, F, Sato, Y, Cajdric, A, Hubbard, N P
Format:	Journal Article
Language:	English
Published:	England 01-07-2001
Subjects:	Adaptation, Ocular - physiology Animals Behavior, Animal - physiology Conditioning, Operant Dark Adaptation - physiology Differential Threshold Electroretinography Male Models, Biological Rats Rats, Sprague-Dawley Retinal Rod Photoreceptor Cells - physiology
Online Access:	Get more information
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	The goal of the present study was to relate the dark and light-adapted flash sensitivity of the scotopic threshold response (STR) and rod b-wave of the electroretinogram (ERG) to behaviorally measured rod increment threshold responses. Small amplitudes of the dark-adapted STR and b-wave, the latter after application of NMDA, were found to increase in proportion to flash intensity. The value obtained for the sensitivity of the b-wave would be expected if signals from rods were summed linearly by the rod bipolar cell. The sensitivity of the STR could not be accounted for in terms of rod signal convergence as the source of this ERG component is still unknown. Increment threshold responses of rats were measured behaviorally in an operant conditioning chamber. At absolute threshold, on average I in 2400 rods were activated by the test flash. Comparison of the adaptive effects of background lights on behaviorally measured scotopic sensitivity and rod ERG sensitivity suggest that the increment threshold sensitivity of rat is regulated at three different sites in the retina.
ISSN:	0952-5238
DOI:	10.1017/S0952523801184142