title: The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay.
abstract: Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-s delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures.
authors.affiliation: Department of Psychology, Box 7037, Davidson College, Davidson, NC 28035-7037, United States, United States.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Strickland
authors.affiliation: Department of Psychology, Box 7037, Davidson College, Davidson, NC 28035-7037, United States, United States.
authors.forename: Max A
authors.initials: MA
authors.lastname: Feinstein
authors.affiliation: Department of Psychology, Box 7037, Davidson College, Davidson, NC 28035-7037, United States, United States.
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Lacy
authors.affiliation: Department of Psychology, Box 7037, Davidson College, Davidson, NC 28035-7037, United States, United States. Electronic address: masmith@davidson.edu.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Smith
mesh_terms: D000818:Animals; D002755:Choice Behavior / Q000502:physiology*; D003216:Conditioning, Operant / Q000502:physiology; D065786:Delay Discounting; D005260:Female; D005502:Food; D007175:Impulsive Behavior / Q000502:physiology*; D009043:Motor Activity / Q000187:drug effects; D010805:Physical Conditioning, Animal / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D012054:Reinforcement, Psychology; D012201:Reward
keywords: Delay discounting; Exercise; Female; Impulsive choice; Physical activity