The hyperkinesia of parakinetic catatonia, which in its early stages may develop only after stimulation, draws its characteristic form from the nature of the movements. Voluntary movements are unnaturally jerky, involuntary movements even more so. Fluid connection between movements is absent: a movement occurs, stops for a moment, and then the next one suddenly begins. The motor process is jerky and grotesque, even when individual movement is accelerated. In terms of content, involuntary movements are characterized by bizarre reactive and distorted expressive movements, with facial expressions appearing vividly in the form of grimaces. Simple movements resemble chorea. In the defect state parakinesia may still be varied, but certain forms are continually repeated as bizarre gestures. The peculiar movement disorder is also expressed in verbalizations. Words are chopped off, produced in isolated jerks, and generally only short, non-grammatical sentences are formed. Oral as well as written utterances of the patients are partly relevant, partly irrelevant, and often non-sensical remarks are found.

Additional cases in the families occurred relatively often and were usually also characteristic of parakinetic catatonia.