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…

Learning to use grapheme to phoneme correspondences (GPCs) provides a powerful mechanism for the foundation of reading skills in children. However, for some children, such as those with Developmental Language Disorder (DLD), the GPC learning process takes time, is laborious, and impacts the entire reading and spelling processes. The present study…

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…

Five individuals with autism or other developmental disabilities participated in paired-stimulus preference assessments during repeated baseline probes. All subjects initially showed a pronounced bias by typically selecting the stimulus placed in either the left or right position. Biased responding for 3 subjects was eliminated when training…

In a recent article published in "The Behavior Analyst," Stewart, McElwee, and Ming (2010) suggested that "scientific experts in scientific contexts" should use more "technically accurate and precise labeling" when describing the Assessment of Basic Learning Abilities (ABLA) in published articles. They concluded by stating, "We believe that…

Level 6 of the Assessment of Basic Learning Abilities (ABLA) assesses the ease or difficulty with which persons with developmental disabilities are able to learn a two-choice auditory-visual discrimination. We investigated whether participants who passed ABLA Level 6 (Group 1) would more readily learn object naming (vocal tacts) than those who…

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…

Williams Syndrome (WS) is a rare neurodevelopmental disorder, which stems from a genetic deletion on chromosome 7 and causes a profound weakness in visuospatial cognition. Our current study explores how orientation perception may contribute to the visuospatial deficits in WS. In Experiment 1, we found that WS individuals and normal 3-4 year olds…

The American Academy of Pediatrics recommends vision screening of all children between 3 and 5 years of age, and states have mandated vision screening for all school children. Participants were three 4-6-year old school children with either a developmental delay or autism who scored "could not test" on the state required vision screening.…

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…

We examined the relationship between three discrimination skills (visual, visual matching-to-sample, and auditory-visual) and four stimulus modalities (object, picture, spoken, and video) in assessing preferences of leisure activities for 7 adults with developmental disabilities. Three discrimination skills were measured using the Assessment of…

Many everyday matching tasks taught to persons with developmental disabilities are visual-visual non-identity matching (VVNM) tasks, such as matching the printed word DOG to a picture of a dog, or matching a sock to a shoe. Research has shown that, for participants who have failed a VVNM prototype task, it is very difficult to teach them various…

Background: Prior studies have showed that presentation methods could affect the accuracy of a choice assessment. Methods: In the current study, high- and low- preferred work tasks were identified in nine adults with developmental disabilities. Both tasks were then introduced in pairs within a choice assessment using the actual tasks, pictures of…

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…