Behavior analysts typically teach conditional discriminations in a mixed-trial format but may switch to a blocked-trial format for learners displaying limited acquisition. No known research has shown that mixed-trial methods are more effective or efficient than blocked-trial methods for teaching discriminations, so it is not clear why this format…

Individuals with Prader-Willi Syndrome (PWS) are at risk for autism spectrum disorder (ASD), including socialization problems. The PWS chromosome 15q11-13 maternal uniparental disomy (mUPD) subtype displays greater ASD symptoms than the paternal deletion (DEL) subtype. Since interpreting faces leads to successful socialization, we compared face…

Williams Syndrome (WS) is a developmental disorder typified by deficits in visuospatial cognition. To understand the nature of this deficit, we characterized how people with WS perceive visual orientation, a fundamental ability related to object identification. We compared WS participants to typically developing children (3-6 years of age) and…

Previous studies indicate that Multiple Complex Developmental Disorder (MCDD) children differ from PDD-NOS and autistic children on a symptom level and on psychophysiological functioning. Children with MCDD (n = 21) and PDD-NOS (n = 62) were compared on two facets of social-cognitive functioning: identification of neutral faces and facial…

Visual perception may be a developmental prerequisite to some types of social understanding. The ability to perceive social information given visual motion appears to develop early. However, children with autism have profound deficits in social cognitive function and may fail to see social motion in the same way that typically developing children…