SECONDARY AND SYNDROMIC STEREOTYPIES

Objective: To determine what is presently known or hypothesized about secondary or syndromic stereotypies and to discuss whether the pathophysiology of primary and secondary stereotypies is different.

Methods: Review of the literature of secondary and syndromic stereotypies.

Results: Systematic studies of secondary versus primary stereotypies are lacking. It has been suggested that a classification system of stereotypies should include primary or “physiologic stereotypies” versus secondary or syndromic stereotypies. In this latter group the stereotypical movements are present in individuals with other independent neurological diagnoses such as mental retardation or autism or in specific syndromes such as Rett or in syndromes caused by congenital cerebellar lesions. Although the suggestion has been made that associated or syndromic stereotypies or secondary stereotypies can be differentiated at a phenomenological or neurobiological level from primary or “physiologic stereotypies” there is little or no data to support this hypothesis.

Conclusion: Our understanding of stereotypies in children with neurological disorders is limited. Systematic study of stereotypies is needed in specific syndromes such as autism in which there is a high association of stereotypies.

Keywords: stereotypies, autism, neurological syndromes