Gray matter volume abnormalities and externalizing symptoms in subjects at high risk for alcohol dependence
Addiction Biology 12 (1), 122–132.
- Vivek Benegal1
- 1Departments of Psychiatry, Vivek Benegal, Deaddiction Centre, Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore 560029, India. E-mail: vbenegal@gmail.com ,
- George Antony1
- 1Departments of Psychiatry, ,
- Ganesan Venkatasubramanian1
- 1Departments of Psychiatry, &
- Peruvumba N. Jayakumar2
- 2Neuroimaging & Interventional Radiology, National Institute of Mental Health & Neurosciences, Bangalore 560029, India
ABSTRACT
Reduced right amygdala volumes have been reported in young, alcohol-naïve subjects at high risk (HR) for alcohol dependence. The differences in brain morphometry have been associated with an excess of externalizing behaviors in these subjects. This may reflect a neurobiological vulnerability to alcohol dependence.
Existing Magnetic Resonance Imaging (MRI) studies on these subjects have examined only a few, pre-selected brain regions using the manual regions of interest (ROI) approach.
MRI of HR subjects (n = 20) and age, sex, and handedness-matched low-risk (LR) subjects (n = 21) were analyzed using optimized voxel-based morphometry and ROI approach.
The externalizing symptoms of these subjects and their fathers were measured using the Semi-Structured Assessment for the Genetics of Alcoholism.
HR subjects had significantly smaller volumes of superior frontal, cingulate and parahippocampal gyri, amygdala, thalamus and cerebellum. These gray matter volumes correlated negatively with externalizing symptoms scores.
Subjects at HR for alcoholism have reduced volumes of critical areas of brain gray matter, which are associated with increased externalizing symptoms. These represent key endophenotypes of alcoholism.