Fein and colleagues (Andrew and Fein 2010b; Gilmore and Fein 2012) have recently reported increased event-related synchronization (ERS) of induced theta activity in two different samples of long-term abstinent alcoholics (LTAA), compared to age- and gender-comparable controls in a three-condition visual oddball task. Event-related oscillatory activity, extracted with time-frequency (TF) methods, represents frequency-specific event-related changes in the ongoing EEG, and is distinguished by whether they are phase locked to the stimulus (Kalcher and Pfurtscheller 1995; Pfurtscheller and Lopes da Silva 1999). TF activity that is phase locked to the stimulus is referred to as evoked oscillations, while non-stimulus-phase-locked activity is termed induced oscillations (Klimesch et al. 1998). Theta ERS is an increase in induced theta (3–7 Hz) power relative to prestimulus values (Kalcher and Pfurtscheller 1995; Pfurtscheller and Lopes da Silva 1999).
