EEG low-voltage alpha and alpha power in African American young adults: relation to family history of alcoholism.
BACKGROUND
Several studies support an association between having a low-voltage EEG and alcohol dependence; however, it is not clear whether this measure represents a risk marker or is a result of years of heavy drinking. The present study's aims were to investigate the prevalence of low-voltage alpha EEG variants in African American young adults who have not yet developed alcohol dependence and to test for associations between low-voltage alpha (LVA) EEG, alpha power, and a family history of alcohol dependence.


METHODS
Clinical ratings and spectral characteristics of the EEG, collected using bipolar recordings, were investigated in 81 African American young adult men and women (18-25 years old) who had no personal history of alcohol dependence. Information on psychiatric diagnoses, personality features, personal drinking and drug use history, and family history (FH) of alcoholism was obtained.


RESULTS
Thirty-two percent (n = 26) of the participants had an LVA EEG variant, and an additional 22% (n = 18) had borderline LVA. The presence of an LVA variant was not associated with drinking status, a family history of alcoholism, or a personal history of anxiety disorders but was associated with significantly higher extroversion scores. Participants who had an FH of alcoholism had significantly higher spectral power in the slow alpha frequencies (7.5-9 Hz). FH was not associated with any significant differences in any other EEG frequency band.


CONCLUSIONS
These findings suggest that considerable ethic variation may exist in the prevalence of LVA EEG variants. In addition, like findings in other populations of non-African descent, having an FH of alcohol dependence may be associated with significantly higher voltage in the alpha frequency ranges.