in particular. GABRA2 encodes the α2 subunit of the GABAA receptor, and inhibitory GABAergic interneurons are centrally involved in producing high frequency oscillations, particularly those in the beta and gamma range. The specific frequency of oscillations in neuronal networks is dependent on the magnitude and kinetics of inhibitory synaptic potentials between interneurons mediated specifically by GABAA receptors (Whittington et al., 2000). Of course, this is not the only source of beta activity; coherent oscillations of excitatory neurons represent another important mechanism (Whittington et al., 2000). Nevertheless, GABAergic activity is clearly particularly important for “inhibition-based” high-frequency rhythms. In addition, a number of studies have reported associations between the GABRA2 gene and externalizing spectrum disorders, such as heavy drinking or alcohol or drug dependence (Agrawal et al., 2006; Bauer et al., 2007; Covault, Gelernter, Hesselbrock, Nellissery, & Kranzler, 2004; Drgon, D’Addario, & Uhl, 2006; Edenberg et al., 2004; Enoch, Schwartz, Albaugh, Virkkunen, & Goldman, 2006; Fehr et al., 2006; Soyka et al., 2008), perhaps with anxiety (Enoch et al., 2006), and antisocial personality (Dick, Agrawal, et al., 2006; Dick, Bierut, et al., 2006), or related personality traits (Villafuerte, Strumba, Stoltenberg, Zucker, & Burmeister, 2013). GABRA2 has been implicated in schizophrenia as well
