Hyperactive behavior and EEG arousal reactions in children.

EEG arousal reactions and parameters of spontaneous EEG activity were studied in two extreme groups of behavior problem children (11 hyperactives and 11 non-hyperactives), selected on the basis of a rating of motor restlessness the core symptom of the "hyperactivity syndrome". The EEG was recorded in three reaction time experiments: a tone light conditioning paradigm and two series with random stimulation. An automatic analysis of EEG parameters was employed to describe the time functions of alpha amplitudes in the single trial. The main findings are: 1. In periods free from stimulation, hyperactive children have higher alpha and beta amplitudes, more alpha waves and a smaller amount of beta waves. This indicates a lower state of EEG arousal in the hyperactives. 2. The amplitude reduction to tone (in the single trial) develops more slowly in the hyperactive group. This group difference increases over the experimental situations. 3. The arousal responses to tone, in terms of the level of maximum amplitude reduction, become comparably weaker in the hyperactives across the experiments. 4. Under all experimental conditions the hyperactives exhibit shorter arousal responses to the light stimulus than the non-hyperactive children. 5. Reaction time performance of the groups is clearly different, hyperactives showing the longer latencies. 6. Although conditional changes in the arousal reactions to both stimuli are reliably demonstrable in all children, the groups show no difference in the corresponding measures. These findings are discussed under the aspects of activation and of attention behavior of the subjects.