A small proportion of video game players develop uncontrolled gaming behavior. A dysfunctional cognitive control circuit may explain this excessive behavior. Therefore, the current study investigated whether problem garners are characterized by deficits in various aspects of cognitive control (inhibitory control, error processing, attentional control) by measuring brain activation using functional magnetic resonance imaging during Go-NoGo and Stroop task performance. In addition, both impulsivity and attentional control were measured using self-reports. Participants comprised 18 problem garners who were compared with 16 matched casual gaming controls. Results indicate significantly increased self-reported impulsivity levels and decreased inhibitory control accompanied by reduced brain activation in the left inferior frontal gyrus (IFG) and right inferior parietal lobe (LPL) in problem garners relative to controls. Significant hypoactivation in the left IFG in problem garners was also observed during Stroop task performance, but groups did not differ on behavioral and self-reported measures of attentional control. No evidence was found for reduced error processing in problem garners. In conclusion, the current study provides evidence for reduced inhibitory control in problem garners, while attentional control and error processing were mostly intact. These findings implicate that reduced inhibitory control and elevated impulsivity may constitute a neurocognitive weakness in problem garners. (C) 2015 Elsevier Ireland Ltd. All rights reserved