Cocaine and level of arousal: effects on vigilance task performance of rats.
Rats were food-reinforced for pressing one of two levers in an operant chamber, with the correct lever being indicated by the position of a briefly illuminated light. After stable accuracy levels were achieved, the rats were tested after an injection of either saline or cocaine (2.5 mg/kg) under two conditions. In the "low arousal" condition, animals were tested during the light phase of a 12-hr light-dark cycle and were fed approximately 5 hr prior to testing. In the "high arousal" condition, animals were tested during the dark phase after approximately 28-hr food deprivation. As expected, accuracy was higher and median choice and food retrieval latencies were shorter under the high arousal condition. Contrary to predictions, cocaine enhanced accuracy under both conditions. These results indicate that cocaine-enhanced performance in some tasks is not necessarily dependent on the animal performing at suboptimal arousal levels.
Grilly
D M
DM
Psychology Department, Cleveland State University, OH 44115.
Grogan
T W
TW
D000818:Animals; D001143:Arousal / Q000187:drug effects*; D002755:Choice Behavior / Q000187:drug effects; D003042:Cocaine / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time / Q000187:drug effects
D003042:Cocaine