A patient maintains an unusual posture for an extended period. Before revealing the answer, decide what distinguishes a stereotyped posture from perseveration of posture.

Ask how the posture originated. A stereotyped posture differs from perseveration of posture, in which the posture arose from an examiner's own passive manipulation or occurred fortuitously and is then maintained, whereas a stereotyped posture may be adopted and sustained spontaneously by the patient, with no such external origin required. Perseveration of posture specifically requires that the examiner placed the limb there, or that it arose fortuitously, with the patient then maintaining it without being explicitly asked to, whereas a stereotyped posture can be actively and spontaneously initiated by the patient themselves. The origin of the posture, spontaneous versus externally or fortuitously placed, is the key distinguishing feature between the two.