Enhanced Striatal Dopamine Release to Expectation of Alcohol: A Potential Risk Factor for Alcohol Use Disorder.
Level 4 - case-series / case-control
Case-control experimental challenge study comparing diagnostic and familial risk groups
PubMed 29803635 · doi:10.1016/j.bpsc.2018.03.018
What was done
Participants across three groups—individuals with alcohol use disorder (AUD, n = 15), healthy participants with a positive family history of AUD (n = 16), and healthy participants with a negative family history of AUD (n = 34)—underwent [11C]raclopride positron emission tomography (PET) imaging. Participants consumed a placebo (n = 65) or alcohol (n = 63) beverage in counterbalanced order before PET scanning (128 total scans). Non-displaceable binding potential (BP_ND) and percent change in BP_ND between beverage conditions were measured in striatal subregions alongside subjective beverage ratings.
What was found
Alcohol induced greater dopamine release than placebo in the ventral striatum across all participants (p < .001). There were no significant main effects of group, drink order, or sex on ventral striatal BP_ND or percent change in BP_ND. A significant drink order-by-group interaction emerged (p = .02): family history-positive participants who received placebo first showed lower placebo BP_ND and less difference between placebo and alcohol BP_ND than all other groups, indicating dopamine release evoked by alcohol expectation. Subjective responses demonstrated the same order-by-group interaction pattern. Exact baseline and post-drink binding values were not reported in the abstract.
Why it matters
This study suggests that familial vulnerability to AUD may involve dopaminergic hyper-reactivity to the conditioned expectation of alcohol rather than altered pharmacological response to alcohol itself.
Limits
Subgroup sample sizes were modest (15 AUD, 16 family history-positive). The primary finding depended on a drink order-by-group interaction rather than a direct main effect between groups. Numerical values for binding potentials and effect sizes were omitted from the abstract.
Cited by
- supports People with a family history of alcohol use disorder have a larger dopamine response to the expectation of consuming alcohol than those without a family history.