Anxiogenic effects of high illumination levels assessed with the acoustic startle response in rats.
Previous studies have shown that the amplitude of the acoustic startle reflex is increased by the presentation of aversive stimuli. In the present study, the amplitude of acoustic startle in rats was increased by exposure to high illumination levels. The effect was directly related to the intensity (0, 8, 70, and 700 footlamberts) of illumination (experiment I); was blocked by the anxiolytic compound buspirone (experiment II); and showed little or no habituation with repeated testing (experiment III). These results suggest that the elevation of startle amplitude by light may reflect an unconditioned anxiogenic effect of high illumination levels. The possible utility of this phenomenon as an animal model of anxiety is discussed.
Walker
D L
DL
Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut 06508, USA.
Davis
M
M
D000161:Acoustic Stimulation; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology; D001007:Anxiety / Q000188:drug therapy / Q000523:psychology*; D002065:Buspirone / Q000494:pharmacology; D003213:Conditioning, Psychological / Q000502:physiology; D006185:Habituation, Psychophysiologic; D008029:Lighting; D008297:Male; D010775:Photic Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013216:Reflex, Startle / Q000187:drug effects / Q000502:physiology*
D014151:Anti-Anxiety Agents; D002065:Buspirone