Brain Morphometry and Cognitive Performance in Detoxified Alcohol-Dependents with Preserved Psychosocial Functioning

Abstract

The extent of structural brain damage and related cognitive deficits has been little described in alcohol-dependent individuals with preserved social functioning. Thus, we investigated the relationship between regional alterations, executive performance, and drinking history. Volumes of gray and white matter were assessed using magnetic resonance imaging voxel-based morphometry in healthy men and in detoxified alcohol-dependent men with good psychosocial functioning. Their executive performance was assessed using neuropsychological tests. Regression analyses were carried out in the regions in which volume differences were detected. Decreases in gray matter were detected bilaterally in alcohol-dependents in the dorsolateral frontal cortex (up to 20% lower), and to a lesser extent in the temporal cortex, insula, thalamus, and cerebellum. Decreases in white matter volume were widespread, being up to 10% in corpus callosum. The degradation of neuropsychological performance correlated with gray matter volume decreases in the frontal lobe, insula, hippocampus, thalami and cerebellum, and with white matter decrease in the brainstem. An early age at first drinking was associated with decreased gray matter volumes in the cerebellum, brainstem (pons), and frontal regions. Regional alteration in gray and white matter volume was associated with impairment of executive function despite preserved social and somatic functioning in detoxified patients. Besides involving frontal regions, these findings are consistent with a cerebello-thalamo-cortical model of impaired executive functions in alcohol-dependent individuals.

Diffusion Tensor Tractography in Mesencephalic Bundles: Relation to Mental Flexibility in Detoxified Alcohol-Dependent Subjects

“…Previous investigations on alcoholism have provided evidence of an association between white matter structure in the corpus callosum and certain components of executive functions, eg attention skills and inhibitory control (Schulte et al, 2006). In our own recent study, decreased white matter volume in the midbrain of alcoholdependent subjects was related to impaired performance in two executive tasks: the Trail-Making Test part-B (TMT-B) and the WAIS letter-number sequencing test (LNS; Chanraud et al, 2007). Both tasks invoke cognitive flexibility, a component of executive functions, which is known to influence treatment outcome (Goldman, 1990) and experience-dependent recovery (Roehrich and Goldman, 1993) in chronic alcoholism.…”

Cerebellar Gray Matter Volume Correlates with Duration of Cocaine Use in Cocaine-Dependent Subjects

“…It has been recently reported that alcohol has neurotoxic effects on cerbellum as measured by regionof-interest volumetry and VBM approach (Chanraud et al, 2007;Maschke et al, 2005;Sullivan et al, 2000). Accordingly, we instituted strict inclusionary/exclusionary criteria to minimize the effects of the alcohol confound in this study.…”

Substance Dependence as a Neurological Disorder

“…Moreover, the age subjects reported their first drink and frequency of drinking to "get high" were associated with left-frontal slow alpha electroencephalograph activity. Similarly, Chanraud et al, (2007) reported the age of first drinking was linked with decreased gray matter volume in frontal cortex, cerebellum, and pons using Magnetic Resonance Imaging suggesting that these regions may be more vulnerable to the neurotoxic effects of alcohol during adolescence.…”