Hostname: page-component-848d4c4894-jbqgn Total loading time: 0 Render date: 2024-07-02T19:24:03.913Z Has data issue: false hasContentIssue false

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

Published online by Cambridge University Press:  11 January 2002

FRANK NAARENDORP
Affiliation:
Department of Psychology, Northeastern University, Boston
YOSHINORI SATO
Affiliation:
Department of Psychology, Northeastern University, Boston
AIDA CAJDRIC
Affiliation:
Department of Psychology, Northeastern University, Boston
NICOLE P. HUBBARD
Affiliation:
Department of Psychology, Northeastern University, Boston

Abstract

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 1 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.

Type
Research Article
Copyright
2001 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)