Figure 1.

Whole-brain functional magnetic resonance imaging (fMRI) activation among stimulant-dependent individuals (SDIs) (n=42), siblings (n=49) and healthy controls (n=47) on the Stroop, contrasting congruent from incongruent color-word median response latencies. Four clusters were identified as having significantly different activation on incongruent than congruent conditions, with peak values in the left precentral gyrus (Montreal Neurological Institute coordinates (x, y, z) in millimeters: −44, 4, 34), left inferior frontal gyrus (−50, 14, 28), right caudate (4, 4, 12) and right rolandic operculum (60, −22, 12). Activation in these regions did not differ between groups. (a) Color contrast fMRI activation means by group. Analysis of covariance covariates include gender, smoking status, Alcohol Use Disorder Identification Test (AUDIT) and Beck Depression Inventory (BDI) scores. (b) fMRI group color contrast activations in the four significant clusters, with significant activation in the left inferior frontal and precentral gyrus, and significant deactivation in the right caudate and rolandic operculum on the incongruent compared with congruent color conditions.