Self-injurious and aggressive behaviors are common in fragile X syndrome (FXS). However, little is known about the persistence of these behaviors and associated risk markers. We established the prevalence and persistence of self-injurious and aggressive behaviors over eight years in males with FXS, and associations with risk markers. Results…

Adaptive behavior in mentally retarded males with fragile X syndrome was longitudinally examined in 17 subjects, ages 1 to 17. Findings included relative strength in daily living skills and weakness in socialization only for older subjects, and significant declines in adaptive behavior scores from first to second testing for the older subjects.…

This study reports behavioral and cognitive stability and change in 76 children with autistic spectrum disorders, evaluated at ages 7 and 11. Verbal IQ, performance IQ, severity of autistic characteristics, and social characteristics were analyzed. The study found that IQ and more severe expression of autistic symptoms were very stable. (CR)