Background and aims:
Recent models on the development of behavioral addictions stress the transfer from goal-directed behavior to stimulus-response habits. Administering a Pavlovian-to-instrumental transfer (PIT) paradigm to individuals with risky or non-problematic gaming, we recently reported that shopping-related cues increase instrumental behavior for a shopping-related reward (i.e. shopping voucher) while gaming-related stimuli triggered instrumental behavior for the gaming-reward (i.e. gaming voucher). This was observed even after devaluation of the gaming-reward. We now investigated the predictive value of the ‘Shopping-PIT’- and the ‘Gaming-PIT’-effects regarding gaming disorder symptoms.

Methods:
Data on symptom severity of gaming disorder six months after the baseline assessment were available for 48 individuals with risky gaming and 46 individuals with non-problematic gaming. Hierarchical regression analyses with stepwise inclusion of control variables, the ‘Shopping-PIT’-effect as indicator of responding for a general reward after devaluation of the gaming reward and ‘The Gaming-PIT’-effect after devaluation of the gaming reward as indicator of habitual responding as well as their interaction effects with symptom severity was calculated.

Results:
Higher gaming disorder symptoms at the six-month follow-up assessment were predicted by symptom severity at baseline and the interaction of the ‘Shopping-PIT’-effect with symptom severity at baseline. The ‘Gaming-PIT’-effect after devaluation did not predict symptom severity.

Discussion and Conclusions:
The finding that cue-triggered responding for a general reward contributes to future symptom severity in individuals with higher symptom severity at baseline suggests a cascade model with higher symptom severity leading to stronger cue-triggered reward-related responding which in turn leads to higher symptom severity.