Abnormal white matter integrity and decision-making deficits in alcohol dependence

To date, there is no study that explored the correlation of microstructural changes in the whole brain white matter (WM) and decision-making in alcohol dependent patients (ADP). In the present study, we applied Tract Based Spatial Statistics (TBSS) to study WM changes in ADP compared with healthy controls. We also tested whether there was any relationship between WM integrity and decision-making in ADP. The study included 17 inpatient ADP who had been abstinent for at least 2 weeks before testing and scanning and 16 healthy control subjects. The Iowa Gambling Task (IGT) was used to measure decision-making. Results for the IGT showed a significant group (ADP vs. control) by block interaction. Follow-up univariate analyses of variance showed that the groups were significantly different in the last 20 trails. Four significant clusters were found in which fractional anisotropy was significantly lower in ADP than in control subjects, including the corpus callosum and parietal, occipital and frontal regions. We found significant correlations between impaired IGT performance in the last 20 trials and WM integrity in these regions. Together, these results might help to explain observed decision making deficits in ADP.