Wacker, J., & Gatt, J.M. (2010). Resting posterior versus frontal delta/theta EEG activity is associated with extraversion and the COMT VAL¹⁵⁸MET polymorphism. Neuroscience Letters, 478, 88-92. 

This study provided novel evidence to support the utility of the delta/theta posterior–anterior distribution of the resting EEG as a probe in the dopaminergic basis of extraversion, and the impact of the gene, COMT Val¹⁵⁸Met, in moderating this process.

The full article can be read on Pubmed