Impaired Decision Making is Associated with Poor Inhibition Control in Nonpathological Lottery Gamblers

Previous studies by questionnaires have demonstrated that lottery gamblers who have not meet the criteria of pathological gambler show greater gambling acceptability. However, few empirical evidence of whether such nonpathological lottery gamblers (NPLGs) display the same impairments of decision making with pathological gamblers has been found so far. In present study, NPLGs and matched controls (MCs) were asked to perform the Iowa Gambling Task (IGT) and inter-temporal choice task (ICT). We found that compared to MCs, NPLGs displayed much lower IGT scores, net gains and proportions of advantageous decks in the IGT task and much higher percentages of trials during which smaller-but-sooner rewards were chosen in the ICT. These findings indicate that NPLGs display much more risky and impulsive decision makings, just like pathological gamblers in the previous studies. Next, the Go/NoGo task was employed to explore the role of response inhibition in the impairment of decision making in NPLGs. We found that NPLGs did show much higher commission errors compared to MCs. Moreover, IGT scores, net gain and proportions of advantageous decks were significantly negatively correlated with commission errors, which indicates that poor response inhibition might be involved in the impairments of decision making in NPLGs. To our knowledge, we provided the first empirical evidence of impairment of decision making and its cognitive mechanisms in NPLGs.