In the present study, although reductions in phase locking were found in all frequency ranges investigated, only changes at alpha frequencies were associated with blood ethanol concentrations. EEG power in the alpha frequency ranges is a sensitive measure of the effects of ethanol on the brain (Ehlers and Schuckit, 1988). Alpha activity has been associated with level of alcohol intoxication in previous studies (Ehlers and Schuckit, 1991, Ehlers et al., 1999). In fact, Lukas et al. (1986, 1989) have reported that episodes of EEG alpha activity closely correlated with the subjective experience of ethanol-induced euphoria. It has been suggested that synchronized alpha may reflect the degree of inhibitory activity of central executive processes involved in modifying information processing (Klimesch et al., 2007). Ethanol is also known to produce an increase in motoric and cognitive disinhibition, interpreted as a loss of executive functioning (Rose and Duka, 2007). Additionally, behavioral under-control has been associated with risk for alcohol dependence (Slutske et al., 2002; Zucker et al., 2008). Further studies will be necessary to link changes in alpha phase locking, ethanol consumption, disinhibitory behaviors and executive functioning.
