Background and aims: Internet gaming disorder (IGD) is associated with impaired inhibitory control and more impulsive decision-making. However, it remains unclear whether these associations are cross-sectional or predictive. We aimed to test the hypotheses that lower inhibitory control and more impulsive decision-making correlate with, are predicted by and predict more time spent on gaming and higher IGD severity.

Methods: A stratified convenience sample of 70 male participants (18-21 years) was recruited to achieve broad data variability for hours spent on gaming and IGD severity. In three annual assessments (T1, T2, T3), we measured gaming behaviour and IGD severity using the Video Game Dependency Scale (CSAS-II). Both gaming-related measures were correlates (T1), predictors (T2), or outcomes (T3) of inhibitory control and decision making, which were assessed at T2 using a go/no-go task and an intertemporal-choice task, respectively.

Results: Higher IGD severity at T1 predicted more impulsive decision-making at T2 (β = 0.45, 95% CI = 0.14-0.76). Lower inhibitory control at T2 predicted more hours spent on gaming at T3 (β = -0.13, 95% CI = -0.25 to -0.02). We found weak or no evidence for the other associations.

Discussion and conclusions: Lower inhibitory control predicts more time spent gaming, possibly due to insufficient top-down regulation of the behaviour. Impulsive decision-making is rather a consequence of IGD than a predictor, which may be due to altered reward learning. One-dimensional etiological assumptions about the relationship between neurocognitive impairments and IGD seem not to be appropriate for the complexity of the disorder.