The present study is directed toward investigating whether the hyperponesis found in schizophrenics plays some type of etiologic role in the schizophrenic process or is merely a consequence of the disorder. Hyperponesis is a neurophysiologic state measurable electromyographically.Four schizophrenic patients were followed chronologically by means of serial multi-channel integrated EMGs so that time relationships between neurophysiologic state and clinical condition could be determined. Results were analyzed statistically.It was found that schizophrenics in remission exhibited an intermittent hyperponesis whose lability increased and/or baseline rose prior to relapse. A persistent hyperponesis was present during the exacerbation. A reduction in the hyperponesis, whether chlorpromazine-induced or spontaneous, was followed by improvement in the patient's clinical condition.After a consideration of several possibilities and the available evidence, the followig hypothesis was suggested: Hyperponesis is a form of energy expenditure within the nervous system, a way of reacting to environment and self, that has detrimental effects on nervous system function. It can trigger a schizophrenic exacerbation in a nervous system prone to schizophrenic reactions through inherited or acquired characteristics. When the hyperponesis is diminished adequately, by whatever means, the nervous system is freed from this deleterious influence and can return to a state of better functioning.