Evaluating the effect of an individualised reward-related impulsivity induction on ad libitum alcohol consumption: A pilot study

Impulsivity has well-documented associations with risky alcohol use. Little evidence exists on the causal mechanisms, but emerging experimental evidence suggests a role for reward-related impulsivity. Recent work experimentally increased reward-related impulsivity to increase drinking using standardised reward-cue stimuli. The present study piloted participant-generated reward-cue stimuli to increase laboratory alcohol consumption. Sixteen participants (56.3 % male; M_age = 20.13, SD = 1.78) attended two laboratory sessions (experimental and control). In the experimental session, the Individualised Reward-seeking Induction Schedule (IRIS) had participants re-experience an intense, vivid memory of an approach motivational state (control session: no induction) before completing a laboratory drinking task. Self-reported reward-seeking, positive, and negative affect were measured. IRIS significantly increased alcohol consumption by 53.65 ml (SE = 29.11, p <.001) when controlling for positive and negative affect. IRIS also produced significantly higher state reward-seeking (Δꭓ² (1) = 14.02, p <.001). Findings provide preliminary validation of IRIS, a new experimental methodology to investigate impulsivity-related alcohol use. Replication of observed effects in a larger sample is required. The present study supports the use of IRIS in future research to understand the causal role of reward-related impulsivity on alcohol consumption.