Who fails the Iowa Gambling Test (IGT)? Personality, neuropsychological, and near-infrared spectroscopy findings in healthy young controls.

The Iowa gambling task (IGT) was designed to assess clinically relevant decision-making impairment, yet some studies find high rates of failure in otherwise healthy control groups. The current study examined variables potentially related to IGT failure, including negative affect, intellect, personality, and executive functioning, in a well-screened sample of healthy young adults. In addition, cerebral oxygenation (near-infrared spectroscopy) was assessed. Results indicated that those who failed the IGT had lower estimated intellect, made more commission errors on the 2-back task, and showed less bilateral dorsolateral prefrontal cortex oxygenation, relative to those who passed. Overall findings are consistent with prior literature suggesting that frontal lobe functioning is related to successful IGT performance and that executive functioning and working memory skills are important components of IGT performance, even in those without clinical disorders or evidence of "real world" dysfunction.