Studies using DTI have detected untoward effects of alcoholism on the microstructure of white matter. In some cases, DTI has been shown to be more sensitive than conventional volumetric MRI in identifying disordered tissue (Pfefferbaum et al., 2000; Pfefferbaum and Sullivan, 2002). One pattern of spared and affected tissue that has emerged over a series of studies using quantitative fiber tracking is that frontal and superior fiber bundles show greater abnormalities than posterior and inferior fiber bundles in alcoholics relative to controls (Pfefferbaum et al., 2009; Pfefferbaum et al., 2010). Using Tract-Based Spatial Statistics (Smith et al., 2006) for DTI analysis, Meyerhoff and colleagues reported lower FA and higher diffusivity, indicative of tissue degradation, in dorsomedial and dorsolateral prefrontal cortical and cerebellar regions (Yeh et al., 2009). Another quantitative fiber tracking study revealed fewer white matter fibers per unit volume running between the midbrain and the pons in alcoholics than controls (Chanraud et al., 2009). Together, these DTI studies indicate a frontal selectivity to white matter damage in the context of widespread microstructural degradation of white matter systems (Pfefferbaum et
