1. No difference was observed in speed of reaction when a group of patients with schizophrenic illnesses was compared to a control group.2. Previously reported differential responsiveness of patients and controls to variation in length of preparatory interval and regularity of stimulus presentation was not observed. The usefulness of such a technique for differentiating schizophrenics from normals is questioned.3. Variability of speed of reaction tends to be significantly greater in the patient group. This result is consistent with previous findings. It is suggested that this represents an increase in the amplitude of fluctuations in readiness which are oscillatory in character.