Communication deficits in infants and toddlers with developmental disabilities

A systematic review of acquisition and mastery of skills taught using the Picture Exchange Communication System

The Picture Exchange Communication System (PECS) is a popular augmentative and alternative communication intervention for individuals with developmental disabilities that includes six, sequential phases of instruction. We systematically reviewed published and unpublished single-case PECS studies for details about the percentage of participants mastering PECS phases, how long it took participants to master PECS phases (in trials to mastery), and what constituted mastery of PECS phases. We found most participants mastered only the first two phases of PECS, and Phases I, II, and IV showed the slowest and widest variability in trials to mastery. Moreover, participants who were taught the third PECS phase learned to select from an average array of three symbols, which may limit the range of messages they can communicate. We discuss our findings in light of a few important limitations and provide directions for future researchers along with recommendations for professionals who might consider PECS.

Nouns and predicates comprehension and production in children with Down syndrome

Our study investigated the lexical comprehension and production abilities as well as gestural production taking into account different lexical categories, namely nouns and predicates. Fourteen children with DS (34 months of developmental age) and a comparison group of 14 typically developing children (TD) matched for gender and developmental age were assessed through a test of lexical comprehension and production (PiNG) and the Italian MB-CDI. Children with DS showed a general weakness in lexical comprehension and production that appeared more evident when the lexicon was assessed through a structured test such as the PiNG that requires general cognitive skills that are impaired in children with DS. As for the composition of the lexical repertoire, for both groups of children, nouns are understood and produced in higher percentages compared to predicates. Children with DS produced more representational gestures than TD children in the comprehension tasks and above all with predicates; on the contrary, both groups of children exhibited the same number of gestures on the MB-CDI and during the subtests of PiNG production. Children with DS produced more unimodal gestural answers than the control group. Theoretical implications of these results are discussed.

An investigation of self-injurious behaviors in adults with severe intellectual disabilities

Self-injurious behavior (SIB) is commonly observed among individuals with intellectual disability (ID) living in state-run supports and services centers. Specific examples of SIB include poking oneself in the eye; harming oneself by hitting, scratching, or pinching; and pica (i.e., swallowing objects causing bodily harm). Previous research has focused on SIB in individuals with ID more generally without focusing on specific levels of ID or taking into account other important personal variables. This study examined 45 adults with severe ID living in two large state-run facilities in the Southeastern United States who were separated into groups for comparison (ASD and non ASD; verbal and nonverbal). Data was collected on the presence of SIB using the Autism Spectrum Disorder-Problem Behavior Adult Version (ASD-PBA). A two-way analysis of variance (ANOVA) was conducted to determine if there were significant differences between groups on rates of SIB. Individuals with ID and ASD exhibited significantly higher rates of SIB than individuals with only ID, F (1,43)=50.84, p<0.05. Furthermore, verbal individuals had significantly higher rates of SIB than nonverbal individuals, F (1,43)=57.612, p<0.05. There was a significant interaction between the effects of ASD diagnosis and verbal ability on rates of SIB, F (1,43)=50.84, p<0.05. The implications of these findings in the context of other research on ID, ASD, SIB, and verbal abilities are discussed.

Discriminant analysis of the autism spectrum disorder observation for children

PURPOSE

To run a discriminant analysis on the individual items and the total scale of the ASD-OC to determine if they significantly discriminated between ASD and atypical groups.

METHOD

The measure was administered to 78 children as part of an outpatient evaluation.

RESULTS

The DA revealed that all of the items, excluding five, were significant predictors by themselves. Additionally, Wilks' lambda was significant, λ = 0.16, χ(2)= 115.91, p < 0.001 for the function, indicating that all of the items together significantly discriminated between groups. The DA was run again excluding those items mentioned above and the variability accounted for by all of the items and prediction of group membership decreased. Therefore, all 45 items were retained for inclusion in the final version of the ASD-OC.

CONCLUSION

The ASD-OC is able to discriminate between ASD and atypical groups.

How do researchers define self-injurious behavior?

Self-injurious behavior is commonly observed among persons with intellectual disabilities. However, a second parallel use of this term is used in the general mental health field for self-mutilation. The authors describe these two disorders and how they differ. Characteristics of what we refer to as repetitive self-injurious behavior among persons with intellectual disabilities and risk factors for these behaviors are discussed. We also describe different assessment/testing methods which aid in defining this phenomenon. The implications of these data for research and clinical practice are discussed.