ENHANCED ALCOHOL-SPECIFIC PAVLOVIAN-TO-INSTRUMENTAL TRANSFER IS ASSOCIATED WITH ALCOHOL USE DISORDER

The Pavlovian-to-instrumental transfer (PIT) paradigm assesses how environmental cues influence ongoing instrumental behaviour. Our previous work has linked PIT to high-risk drinking and alcohol use disorder (AUD), but used monetary rewards during learning. We therefore developed a PIT paradigm delivering trial-by-trial alcohol and juice rewards alongside monetary rewards, directly assessing the alcohol-specific PIT effect that may better reflect real-life alcohol-seeking behaviour.
Seventy-five participants with AUD and nighty-five controls completed the task during fMRI. Alcohol-specific PIT was defined as more alcohol choices during presentation of alcohol-associated versus juice-associated cues. General PIT was defined as increased response vigor during display of positively-valenced cues (€10) versus negatively-valenced cues (€-10). The AUD group showed enhanced alcohol-specific PIT effect compared to controls (p < .001; r = 0.295). Alcohol-specific PIT effect was also associated with the Alcohol Use Disorder Identification Test (AUDIT; rho = 0.287; p < .001). In contrast, general PIT effect showed no associations with groups (p = .698; r = 0.030) or AUDIT (rho = -0.143; p = .075). At the neural level, alcohol cues elicited stronger anterior insula responses. Region of interest (ROI) analysis showed a greater left-amygdala alcohol>juice response in AUD than in controls (p = .043; Cohen’d = 0.323). For general PIT, gain>loss engaged putamen, amygdala, and ventromedial prefrontal cortex responded, and these ROI responses correlated with behavioural general PIT.
These findings indicate that alcohol cues exert a greater influence on alcohol-seeking in AUD, potentially linked to elevated amygdala responses to alcohol relative to alternative rewards.