Locomotor activity predicts acquisition of self-administration behavior but not cocaine intake.
The current study investigates locomotor activity in a novel environment and correlates these activity levels with cocaine self-administration in rats that were either trained or untrained on a lever-pressing task prior to cocaine self-administration. The authors report that it is the rate of learning the lever-pressing task, not cocaine self-administration, that correlates with locomotor activity. The results suggest that a correlation between locomotor activity and cocaine self-administration is secondary to a link between locomotor activity and rate of learning to lever press for a reward. The authors conclude that locomotor activity is not necessarily an indicator of propensity to self-administer cocaine and demonstrate that environmental novelty and rate of learning an operant task are important considerations when designing experiments on drug-seeking behaviors.
Mitchell
Jennifer M
JM
Department of Neurology, University of California, San Francisco, CA 94143, USA. juniper@itsa.ucsf.edu
Cunningham
Chris L
CL
Mark
Gregory P
GP
D000818:Animals; D003042:Cocaine / Q000008:administration & dosage* / Q000494:pharmacology*; D003216:Conditioning, Operant; D018765:Dopamine Uptake Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology*; D005106:Exploratory Behavior; D007858:Learning; D008297:Male; D009043:Motor Activity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology; D012646:Self Administration
D018765:Dopamine Uptake Inhibitors; D003042:Cocaine