Abstract
Existing models are currently inadequate in explaining the relationship between habitual decision-making and different expressions of addictive behaviors. The current study investigates the role of psychological distress as a key factor in disrupting decision-making processes in the context of substance and behavioral addictions. A large community sample (N = 668) completed a gamified two-stage task to investigate the link between model-free (habitual) task behavior and a wide range of addictive behaviors. Addictive behaviors included substance use (alcohol, nicotine, and illicit drug use) and behavioral addictions (problematic use of the internet, addictive eating, shopping, and gambling). The relationship between habitual task behavior and addictive engagement was investigated using structural equation modelling with a bifactor latent variable structure, which was modeled and tested; one for substance use and one for behavioral addictions. For participants with higher levels of psychological distress, greater habitual task behavior was a significant predictor of behavioral addiction risk (β = -0.188, SE = 2.061, p = .016), specifically problematic use of the internet (β = -0.148, SE = 0.045, p = .018) and eating behaviors (β = -0.191, SE = 0.016, p < .001). These findings support our proposition that psychological distress disrupts cognitive control, leading to a greater reliance on habitual decision-making and non-substance addictive behaviors. This highlights the potential importance of habit-based interventions in combination with stress-reduction and mental health-promoting techniques to improve outcomes and minimize harm, especially in the context of behavioral addictions.