One method of improving measures of behavior is through new techniques in quantitative electrophysiology. Quantitative electrophysiology uses computerized analyses of the electroencephalogram and sensory-evoked responses to measure brain development objectively. The use of these techniques involves referencing an individual to a large normative data base of standardized brain measures. In contrast to conventional psychometric measures, electrophysiological measures more directly assess brain functions. These measures can identify any organic basis for learning disabilities and detect brain abnormalities that may produce maladaptive behavior. Electrophysiological assessments can also assess brain responses to changes in medicinal regimens and other treatments. Significant predictors of antisocial behavior can be isolated and addressed to prevent the onset of such behavior. 5 figures and 116 references.