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Topographic measures of electroencephalographic (EEG) amplitude were used to compare recovered alcoholics (n = 14) with sex- and age-matched control subjects. Delta, alpha, and beta activity did not distinguish the groups, but regional differences in theta distribution did. Recovered alcoholics showed more uniform distributions of theta amplitudes in bilateral anterior and posterior regions compared with controls. Because a minimum of 5 years had elapsed since the recovered alcoholic subjects fulfilled DSM-III-R criteria for alcohol abuse or dependence, it is unlikely these EEG theta differences reflect the effects of withdrawal.

Reliabilities of quantitative measures of absolute and relative EEG amplitudes were assessed in healthy older adults under the eyes closed (n = 46) and eyes opened (n = 45) conditions. For the theta, alpha, beta 1, and beta 2 bands, reliabilities of 28 scalp derivations were stable over the 4.5 month test interval. Reliabilities of delta were lower. When appropriate transformations were applied, the reliabilities of absolute EEG amplitude measures tended to exceed those of relative measures. There were not, however, striking differences in reliabilities under the eyes closed, as compared to eyes opened condition. We concluded that when coupled with the criterion of interpretability, the generally higher reliabilities of absolute, as opposed to relative, amplitude measures render them preferable in clinical research.

Some previous quantitative EEG research indicates that depressed subjects show increased alpha and beta compared to controls. In this report, absolute and relative amplitude measures of topographic EEG were used to compare elderly subjects with major depression to sex and age matched control subjects. Elderly depressed subjects showed significantly higher absolute alpha amplitude than controls, but regional differences did not specifically distinguish them. Relative alpha amplitudes, and absolute and relative measures of beta, delta, and theta did not reliably distinguish depressed and control subjects. The results are discussed in the context of previous EEG research in depression and the elderly. Methodological features and the implications of these findings for state and trait dependent conceptualizations of depression are considered.

Research published in the past decade that used quantitative indices to evaluate the waking EEG characteristics of depressed patients is reviewed. Methodological problems that make results of different research laboratories difficult to compare include diagnostic heterogeneity of depressed groups, lack of inclusion of control subjects, and differences in the EEG techniques. Despite interpretive problems that arise from such substantial variation, consistencies nevertheless emerge. Unmedicated, actively depressed patients appear to exhibit elevated EEG alpha and beta compared to control subjects. Delta and theta distinguished depressed patients from controls in some single studies, but variation in age, specific diagnostic depression categories, and EEG acquisition and analysis techniques rendered these results less definitive. Quantitative EEG differences that may distinguish depressed subject samples from those with other psychiatric disorders are considered. Factors that limit comparability of the findings are discussed in conjunction with strategies that deserve systematic study in future research.

The interindividual distributions of EEG amplitudes were evaluated in 60 healthy subjects, aged 56-76. Skew and kurtosis were used to assess the normality of the amplitude distributions in 5 frequency bands (delta, theta, alpha and 2 beta ranges) and 28 scalp derivations while the subjects were awake and rested with their eyes closed and opened. Most of the interindividual EEG amplitude distributions were not normally distributed. Two transformations were applied to the EEG amplitudes: the square root and the natural logarithm. Evaluation of skew and kurtosis indicated that the natural logarithmic transformation was more effective than the square root in reducing the positive skew and leptokurtosis that characterized the untransformed interindividual EEG amplitude distributions. For all frequency bands except theta, the log transformation rendered the distributions approximately normal in form. Correlations between log transformed EEG amplitudes and age were not statistically significant. These findings are discussed in the context of previous research, aging, and methodological features.

Late-middle-aged and elderly normal volunteers with past histories of Major Depression according to the Diagnostic and Statistical Manual of Mental Disorders (third edition-revised) criteria were compared with sex- and age-matched control subjects using topographic electroencephalographic (EEG) indices. Healthy, euthymic recovered depressed subjects showed greater alpha amplitudes than controls. Delta, theta, and beta amplitudes did not reliably distinguish the groups. Considered in the context of previous research indicating that actively depressed subjects exhibit elevated EEG alpha compared to controls, these findings raise questions concerning state and trait conceptualizations of depression and EEG alpha.

The use of low-dose L-deprenyl, a selective MAO-B inhibitor, in Alzheimer's disease patients has been associated previ ously with improvements in agitation and episodic learning and memory. Behavioral, cognitive, and regional electroen cephalogram (EEG) measures were obtained in a 4-week open pilot study of 14 patients with probable Alzheimer's disease by NINCDS criteria who were administered 10 mg L-deprenyl per day. L-Deprenyl administration was associated with significant improvements on the agitation and depression factors of the Brief Psychiatric Rating Scale, the Cornell Scale for Depression in Dementia, and spouses' blind ratings. Recall improved on the Buschke Selective Reminding Task, but intrusions also tended to increase; verbal fluency decreased. Absolute EEG delta measures were selectively sup pressed in the right frontal region. The pattern of changes suggests that L-deprenyl may be associated with improvement in behavioral and cognitive performance, in part through a mild behavioral disinhibiting effect. (J Geriatr Psychiatry Neurol 1991;4:143-148). [ABSTRACT FROM PUBLISHER]