In an extension of our prior work [19–21], data were available on 116 individuals comprised of 58 matched pairs of low and high LR subjects. The sample generated 232 fMRI sessions with alcohol and placebo runs, along with 116 alcohol challenges carried out prior to imaging sessions. As shown in Table 1, the two LR groups were well matched on demography, drinking frequency, as well as tobacco and cannabis use, with resulting similar BACs at 60 minutes, a time close to administration of the Hariri task. Low LR subjects also reported a higher number of drinks per occasion, which could have contributed to the low LR through acquisition of intersession tolerance, thus confounding the determination of a low LR. Therefore, this variable was used as a covariate in all fMRI analyses.
