Susceptibility to interference between Pavlovian and instrumental control predicts alcohol use trajectories in young adults

Appetitive Pavlovian cues promote approach and inhibit avoidance, while aversive Pavlovian cues inhibit approach and promote avoidance behaviour. Typically this interaction is adaptive, but in some contexts the modulation is non-adaptive. The interaction between Pavlovian and instrumental action control can be studied Pavlovian-to-instrumental transfer (PIT) tasks. We previously found that susceptibility to the interference between Pavlovian and instrumental control was associated with risky alcohol use in males at age 18.

Drinking trajectories of 117 participants were assessed from ages 18 to 24 with the Alcohol Use Disorders Identification Test (consumption score) and a gram/drinking occasion measure (binge drinking score). The PIT task was assessed at ages 18 and 21 during fMRI. Interference was characterized by the increase of error rates (ER) during conflict (collecting shells in the presence of a negatively valenced Pavlovian cue, or leaving shells during presentation of positively valenced cue) compared to non-conflict trials. 62%/66% participants showed PIT interference at ages 18 and 21, respectively. Interference scores were at both time points were modestly correlated (r=0.29, p=0.002). At the neural level the interference PIT effect was assessed via brain responses in the ventral striatum (VS), lateral and dorsomedial prefrontal cortices (lPFC and dmPFC). Latent growth curve modelling was applied to investigate whether interference predicts drinking trajectories.

At age 18 we found a cross-sectional association between stronger VS activity during conflict and the consumption (p=0.010) and binging scores (p=0.004). VS activity at age 18 also predicted the decrease of the binging score (p=0.035). At age 21 higher behavioural interference (ER) and dmPFC responses during conflict were associated with a stronger increase in the consumption score until age 24 (p=0.009 and p=0.043, respectively).

Our data suggest that increased susceptibility to interference between Pavlovian and instrumental action control might be a relevant mechanism underlying the development of hazardous alcohol use in young adults. Future research could investigate whether this mechanism might be a target for novel interventions.