Abstract
AIMS: To use functional magnetic resonance imaging (fMRI) to investigate the neural circuitry behind effort-related valuation and motivation in a population of alcohol-dependent participants and healthy controls. METHODS: Seventeen alcohol-dependent participants and a comparison group of 17 healthy control participants completed an effort-based motivation paradigm during an fMRI scan, in which they were required to exert effort at varying levels in order to earn a monetary reward. RESULTS: We found that alcohol-dependent participants were less motivated during trials requiring high levels of effort. The whole-brain fMRI analysis revealed that alcohol-dependent participants displayed an increased blood-oxygen-level dependent (BOLD) signal during low and unknown effort cues in the dorsal and ventral striatum compared with healthy controls. CONCLUSION: These findings provide the first evidence that alcohol-dependent participants and healthy controls differ in their effort-based valuation and motivation processing. Alcohol-dependent participants displayed a hyperactive mesolimbic reward circuitry recruited by non-drug rewards, potentially reflecting a sensitization to reward in this patient population.