Stereotyped movements in a group of autistic children.

The authors studied the stereotyped movements presented by a group of 20 autistic children, evaluating the patient observation protocols according to a psychodynamic model of autism. The stereotyped movements were analysed considering ten different parameters: type, site, morphology, frequency, association, complexity, active sensory channel, trigger event, affect during stereotyped movement, and function. The results indicate that each autistic child possesses highly idiosyncratic "stereotypical behavioural equipment", which includes behaviours ranging from simple, reflex-like actions, to much more complex movement patterns. Stereotyped movements were found to appear, in response to different stimuli, at moments when the subject's psychophysical state needed "resetting". Eight possible functions of stereotyped movements were identified. These correspond to two main purposes: reinforcement or weakening of the autistic barrier. The need for rehabilitation is questioned, since not all stereotyped behaviours interfere with explorative and cognitive activities.