Shared Features or Co-occurrence? Evaluating Symptoms of Developmental Coordination Disorder in Children and Adolescents with Autism Spectrum Disorder.

Motor differences are common in Autism Spectrum Disorder (ASD), but rarely evaluated against diagnostic criteria for Developmental Coordination Disorder (DCD). We aimed to determine whether motor problems in ASD represent the possible co-occurrence of DCD. We retrospectively reviewed standardized assessments and parent-reports to evaluate motor ability in 43 individuals with ASD against diagnostic criteria for DCD, and compared to 18 individuals with DCD. Over 97% of cases in the ASD group scored below the 16th percentile in motor ability, with most below the 5th percentile. Over 90% of cases in the ASD group met criteria for co-occurring DCD. Motor challenges are a clinically-significant problem in ASD; systematically assessing the prevalence of co-occurring ASD + DCD is necessary to optimize assessment and intervention.

Effects of a topical anesthetic on non-socially maintained self-injurious behavior.

In the present study we hypothesized that the self-injurious behavior (SIB) of a 12-year-old male diagnosed as having autism and severe mental retardation was maintained by automatic reinforcement. Further, we hypothesized SIB served a sensory reinforcement function related to sensation at the skin surface. The participant engaged in high rates of SIB in the form of self-slapping. A functional analysis resulted in undifferentiated findings. Additional observations indicated that SIB occurred only to exposed skin surfaces. To test for a sensory function, we applied a topical anesthetic to the participant's skin. SIB was reduced by 20 to 60% after application of the dermal anesthetic. These results support an automatic reinforcement hypothesis. Implications for treatment are discussed.