the Genetics of Alcoholism (COGA), individuals with DSM-IV alcohol dependence (AD) manifested increased resting EEG interhemispheric theta coherence8,9, indicating altered cortico-cortical functional connectivity. Recent work22 identified resting state theta EEG coherence networks that were correlated with resting state executive control networks detected with functional magnetic resonance imaging (fMRI) in prior AD studies; this demonstrates that there is a correspondence between resting state fMRI connectivity and resting-state EEG activity. When compared to light drinkers, individuals with AUD have reduced cortical grey matter23,24 and white matter volumes, and reduced myelination25,26. In addition, individuals with AUD have a smaller corpus callosum25,27, and show disruptions of the integrity of white matter tracts in the corpus callosum on the micro-structural level28, possibly via disruptions in myelination29. Taken together, these findings suggest corpus callosal interhemispheric connections may be disturbed in AUD.
