As explained in Stewart, Bismark, et al. (2010), resting EEG asymmetry derived from AVG, Cz, and LM references has produced an inconsistent pattern of findings, wherein null results between depressed and non-depressed individuals have been reported in several cases (e.g., Bruder et al., 1997; Metzger et al., 2004; Nitschke et al., 1999; Pizzagalli et al., 2002; Reid et al., 1998) and asymmetry results for depressed women have also been more robust than those for men when these montages are utilized (Stewart, Bismark, et al., 2010). In addition, researchers have shown that convergence of AVG, Cz, and LM montages is not particularly high for frontal EEG data collected at rest (Hagemann et al., 2001; Reid et al., 1998). Furthermore, unlike the CSD-transformed data, which is most likely to reflect predominantly frontal sources (Hagemann et al., 2001; Kayser & Tenke, 2006; Kayser & Tenke, 2012), these other references are thought to index both proximal (frontal) and distal (parietal and occipital) sources, so it is not surprising that discrepant findings emerged for resting data as a function of reference mode. CSD is advantageous
