These findings were replicated more recently (Andrew and Fein, 2010a) for evoked and total power in delta and theta ERO in long-term abstinent alcoholics; the authors proposed that P300 and ERO measures provide comparable information. Phase locking enhances signal-to-noise ratios; however the increase in non-phase locked (induced) theta oscillations was suggested to be a marker of chronic alcohol abuse on the brain (Gilmore and Fein, 2012). This effect may recover, at least partially, with extended abstinence. The increased induced theta was also a strong predictor of alcoholism status (Andrew and Fein, 2010b).
