Quantitative EEG abnormalities are associated with memory impairment in recently abstinent methamphetamine-dependent individuals

This study examined the association between brain electrical activity, measured using quantitative electroencephalography (QEEG), and performance on measures of episodic memory in a sample of nine methamphetamine-dependent individuals who were evaluated after 4 days of monitored abstinence and 10 non-drug-using comparison subjects. In methamphetamine users, but not in comparison subjects, increased theta power was correlated with poorer performance on the delayed recall subtests of the Rey Auditory Verbal Learning Test and the Rey-Osterrieth Complex Figure Test (p<0.05). There was no association between alpha, beta, and delta power and performance on the memory tests. These results complement previous findings by demonstrating that the electrophysiological abnormalities associated with methamphetamine dependence are likely to affect behavior in an observable and important manner (i.e., memory deficits) when users are not intoxicated.