J Psychiatry Neurosci 2015;40(2):108-117
Michael M. Barrus, BA; Jay G. Hosking, PhD; Fiona D. Zeeb, PhD; Melanie Tremblay, MA; Catharine A. Winstanley, PhD
Background: Impulsivity is understood as a range of behaviours, but the association between these behaviours is not well understood. Although high motor impulsivity is a key symptom of disorders like pathological gambling and addiction, in which decision-making on laboratory tasks is compromised, there have been no clear demonstrations that choice and motor impulsivity are associated in the general population. We examined this association in a large population of rodents.
Methods: We performed a meta-analysis on behavioural data from 211 manipulation-naive male animals that performed a rodent gambling task in our laboratory between 2008 and 2012. The task measures an aspect of both impulsive decision-making and impulsive action, making it possible to evaluate whether these 2 forms of maladaptive behaviour are related.
Results: Our meta-analysis revealed that motor impulsivity was positively correlated with poor decisionmaking under risk. Highly motor impulsive rats were slower to adopt an advantageous choice strategy and quicker to make a choice on individual trials.
Limitations: The data analyzed were limited to that produced by our laboratory and did not include data of other researchers who have used the task.
Conclusion: This work may represent the first demonstration of a clear association between choice and motor impulsivity in a nonclinical population. This lends support to the common practice of studying impulsivity in nonclinical populations to gain insight into impulse control disorders and suggests that differences in impulsive behaviours between clinical and nonclinical populations may be ones of magnitude rather than ones of quality.
Submitted Feb. 10, 2014; Revised May 2, 2014; Accepted June 9, 2014; Early-released Sept. 23, 2014.
Acknowledgements: This work was supported by operating grant funding to C.A. Winstanley from the Canadian Institutes of Health Research (CIHR), The National Sciences and Engineering Council of Canada, the Michael Smith Foundation for Health Research (MSFHR), Parkinson Society Canada, the Institute for Research into Pathological Gambling and Related Disorders (now the National Council for Responsible Gambling) and the Canadian Foundation for Innovation. C.A. Winstanley also receives salary support through the MSFHR and CIHR New Investigator Award program.
Affiliations: From the Department of Psychology, University of British Columbia, Vancouver, BC, Canada (Barrus, Hosking, Zeeb, Tremblay, Winstanley); and the Centre for Addiction and Mental Health, Toronto, Ont., Canada (Zeeb).
Competing interests: None declared.
Contributors: M. Barrus designed the review, performed the analysis and interpretation, prepared the article and can give final approval of the article as submitted. J. Hosking collected data, substantially assisted with the analysis and drafting of the article and can give final approval of the article as submitted. F. Zeeb designed the task, collected data, assisted with the preparation of the article and can give final approval of the article as submitted. M. Tremblay collected data, assisted with preparation of the manuscript and can give final approval of the article as submitted. C. Winstanley provided funding, conceived of the review, substantially assisted with the drafting of the article and can give final approval of the article as submitted.
Correspondence to: M.M. Barrus, Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver BC V6T 1Z4; firstname.lastname@example.org