While few studies have been conducted relating EEG or ERPs to DTI measures, those that have been published have shown promise in informing EEG–white matter relationships. For example, Westlye et al. (2009) reported a significant relationship between transverse diffusivity (λT) in the cingulate bundle and the amplitude of the error-related negativity, thought to be generated in the anterior cingulate. Valdes-Hernandez et al. (2010) also recently reported relationships between FA in posterior white matter (superior and posterior corona radiata and posterior corpus callosum) and the α frequency EEG activity. Herein, the significant regression relations between δ total power at Cz and transverse diffusivity in the left and right cingulate bundles can be interpreted as implicating white matter degradation, and myelin status in particular, with damped NOGO P3 generation in alcoholism and older age (Fjell and Walhovd 2004; Stige et al. 2007; Vallesi et al. 2009).
