Autism as a disorder of prediction.

A rich collection of empirical findings accumulated over the past three decades attests to the diversity of traits that constitute the autism phenotypes. It is unclear whether subsets of these traits share any underlying causality. This lack of a cohesive conceptualization of the disorder has complicated the search for broadly effective therapies, diagnostic markers, and neural/genetic correlates. In this paper, we describe how theoretical considerations and a review of empirical data lead to the hypothesis that some salient aspects of the autism phenotype may be manifestations of an underlying impairment in predictive abilities. With compromised prediction skills, an individual with autism inhabits a seemingly "magical" world wherein events occur unexpectedly and without cause. Immersion in such a capricious environment can prove overwhelming and compromise one's ability to effectively interact with it. If validated, this hypothesis has the potential of providing unifying insights into multiple aspects of autism, with attendant benefits for improving diagnosis and therapy.

Assessing the predictive validity of the admission process in a master's level speech language pathology program.

Astin's Input-Environment-Outcome (I-E-O) model served as the theoretical foundation to assess (a) undergraduate GPA, (b) undergraduate Speech Language Pathology majors, and (c, d) GRE-Q and GRE-V scores (Input) as predictors of students' graduate GPA (Environment), and graduate GPA as a predictor of PRAXIS scores (Outcome). The sample for this study was 122 students who completed the Speech-Language Pathology Program in recent academic cycles at a graduate school in the northeastern United States. The sample was representative of other programs in the country in terms of gender, undergraduate GPA, and GRE scores. Results appear to support the predictive validity of the linear combination of the input predictors of the environment variable (GPA) and of the environment variable on the outcome, i.e., PRAXIS scores.

Age-related impairments in the revision of syntactic misanalyses: effects of prosody.

Two experiments examined whether young and older adults differ in comprehending sentences that contain temporary syntactic closure ambiguities. Experiment 1 examined age-related differences using the Auditory Moving Window (AMW) task, in which sentences were presented in a segment-by-segment self-paced fashion. Experiment 2 examined age-related differences using a sentence recall task, in which sentences were presented in their entirety. Sentences were constructed to have cooperating prosody (i.e., where prosody is consistent with the syntactic boundaries), baseline prosody (i.e., where prosody is ambiguous in the syntactically ambiguous region), and conflicting prosody (i.e., where cross-splicing relocates the prosodic phrase break at a misleading point in syntactic structure). The results showed that both young and older adults make comparable use of prosodic information to interpret temporary syntactic ambiguities, although younger adults may make use of this information more quickly than older adults. In addition, older adults appeared to be less able than young adults to revise initial syntactic misinterpretations caused by conflicting prosodic information. These results are interpreted with respect to age-related impairments in the allocation of working memory resources and inefficient inhibitory function during spoken language processing.

An Investigation of Language Impairment in Autism: Implications for Genetic Subgroups.

Autism involves primary impairments in both language and communication, yet in recent years the main focus of research has been on the communicative deficits that define the population. The study reported in this paper investigated language functioning in a group of 89 children diagnosed with autism using the ADI-R, and meeting DSM-IV criteria. The children, who were between 4- and 14- years-old were administered a battery of standardized language tests tapping phonological, lexical, and higher-order language abilities. The main findings were that among the children with autism there was significant heterogeneity in their language skills, although across all the children, articulation skills were spared. Different subgroups of children with autism were identified on the basis on their performance on the language measures. Some children with autism have normal language skills; for other children, their language skills are significantly below age expectations. The profile of performance across the standardized measures for the language-impaired children with autism was similar to the profile that defines the disorder specific language impairment (or SLI). The implications of this language impaired subgroup in autism for understanding the genetics and definition of both autism and SLI are discussed.