Acute alcohol intake disrupts resting state network topology in healthy social drinkers

Alcohol intake disrupts cognitive and sensory processing. However, its effects on the role of individual structures within cortical networks, or on the larger network structure, remain unclear. This acute alcohol administration study addressed this gap using graph theory analysis. Healthy individuals (n = 107, 21-45yrs, 61 women) consumed alcohol (0.08g/dL target BrAC) or a placebo drink in 2 double-blinded sessions and self-reported their perceived intoxication using a visual analog scale. Resting state fMRI was acquired with a Siemens Prisma 3T scanner 30min after consumption. The effect of alcohol on graph theory outcomes in a network of 106 cerebral ROIs was identified using the CONN toolbox. We also determined the association between graph theory metrics and subjective intoxication. Results revealed alcohol 1) significantly decreased global efficiency in several occipital nodes and increased global efficiency for nodes within the frontal and temporal cortex; 2) increased local efficiency at a network level as well as in specific nodes in the temporal and frontal cortices; 3) increased degree in frontal and temporal regions; 4) decreased closeness centrality and increased mean path length in parietal and occipital regions as well at the network level compared with placebo conditions. Additionally, decreases in global efficiency and increases in local efficiency and clustering coefficient in the alcohol vs. placebo condition significantly predicted subjective intoxication. Taken together, results provide new evidence that alcohol intake produces changes in the overall topography of the cerebral network that at least partially underlie individual differences in subjective alcohol response.