A recent theory holds that a component of the human event-related brain potential called the reward positivity reflects a reward prediction error signal. We investigated this idea in gambling-like task in which, on each trial, a visual stimulus predicted a subsequent rewarding or nonrewarding outcome with 80% probability. Consistent with earlier results, we found that the reward positivity was larger to unexpected than to expected outcomes. In addition, we found that the predictive cues also elicited a reward positivity, as proposed by the theory. These results indicate that the reward positivity reflects the initial assessment of whether a trial will end in success or failure and the reappraisal of that information once the outcome actually occurs.
aDepartment of Psychology, University of Victoria, Victoria
bDepartment of Psychology and Neuroscience, Dalhousie University
cSchool of Population and Public Health, University of British Columbia, British Columbia, Canada
Correspondence to Clay B. Holroyd, PhD, Department of Psychology, University of Victoria, Cornett Building A236, 3800 Finnerty Road (Ring Rd), Victoria, BC V8P 5C2, Canada Tel: +1 250 853 3910; fax: +1 250 721 8929; e-mail: firstname.lastname@example.org
Received January 21, 2011
Accepted February 1, 2011