Cortical and subcortical volumes in adolescents with alcohol dependence but without substance or psychiatric comorbidities

Abstract

Most prior studies of the effects of excessive alcohol intake on the adolescent brain examined alcohol use dependent samples with comorbid psychiatric and substance use disorders. In the Cape Town region, we identified a sizeable cohort of adolescents with alcohol use disorders (AUD) without externalizing or other psychiatric disorders. We examined brain morphology in 64 such adolescents compared to age and gender matched healthy controls. Magnetic resonance imaging data were analyzed using FSL’s FIRST software for subcortical volumes, and cortical gray matter (GM) was analyzed using voxel based morphometry (VBM) and regions of interest (ROI) analysis. AUD boys had smaller thalamic and putamen volumes compared to non-drinking boys, while AUD girls had larger thalamic and putamen volumes compared to non-drinking girls. VBM revealed a large region of decreased GM density in AUDs compared to controls located in the left lateral frontal, temporal, and parietal lobes, extending medially deep into the parietal lobe. Smaller GM volume in this region was also present when examined using ROI analysis. Our lack of findings in other brain regions, particularly hippocampus, suggests that reports of smaller brain volumes in adolescent AUDs in the literature are a consequence of psychiatric and substance abuse comorbidities.

Theory of Mind Difficulties in Patients with Alcohol Dependence: Beyond the Prefrontal Cortex Dysfunction Hypothesis

“…This highlights that ToM deficits in AD individuals cannot be only explained by a frontal lobe dysfunction and that a dysfunction of the temporo-parietal areas could also contribute to explain the deficits. Dysfunctioning of the temporo-parietal junction is in line with evidence of decreased parietal lobe volume in AD adolescents (Fein et al, 2013) and adults (Jernigan et al, 1991;Sullivan, 2003;Sullivan et al, 1996). Furthermore, it has been shown that the parietal lobe volume decrease is positively correlated with alcohol dose (Fein et al, 2009) and predictive of relapse within 90 days (Rando et al, 2011).…”

Structural neuroimaging correlates of alcohol and cannabis use in adolescents and adults

“…Results of our recent large-scale study support a negative correlation between alcohol use severity and global GM volume in adults as young as 18 years [8]. Studies among adolescents suggest regional reductions in frontal [9–11], temporal and parietal [10], and cerebellar volume [12], or differences localized to specific structures such as the hippocampus [13]. Recent longitudinal research has reflected that even minor or moderate alcohol use may have teratogenic effects [14]; and further, that initiation of regular drinking in late adolescence dose-dependently disrupts GM development [15–16].…”

Childhood adversity is linked to differential brain volumes in adolescents with alcohol use disorder: a voxel-based morphometry study

“…In our earlier study (Fein et al 2013) an initial preliminary correlation analysis of early exposure to trauma and brain volumes revealed no significant findings, perhaps due to the region of interest approach taken. It could be that other brain regions, not included in our previous analysis of regions highly implicated in AUD, are associated with the effects of childhood trauma.…”