Self-ordered pointing in children with autism: failure to use verbal mediation in the service of working memory?

This study tested the hypothesis that children with autism are impaired in using verbal encoding and rehearsal strategies in the service of working memory. Participants were 24 high-ability, school-age children with autism and a comparison group matched on verbal and non-verbal IQ, receptive and expressive vocabulary, and visual memory. Working memory was assessed using verbal and non-verbal variants of a non-spatial, self-ordered pointing test [Petrides, M., & Milner, B. (1982). Deficits on subject-ordered tasks after frontal- and temporal-lobe lesions in man. Neuropsychologia, 20, 249-262] in which children had to point to a new stimulus in a set upon each presentation without repeating a previous choice. In the verbal condition, the stimuli were pictures of concrete, nameable objects, whereas in the non-verbal condition, the stimuli were not easily named or verbally encoded. Participants were also administered a verbal span task to assess non-executive verbal rehearsal skills. Although the two groups were equivalent in verbal rehearsal skills, the autism group performed significantly less well in the verbal, but not the non-verbal, self-ordered pointing test. These findings suggested that children with autism are deficient in the use of verbal mediation strategies to maintain and monitor goal-related information in working memory. The findings are discussed in terms of possible autistic impairments in episodic memory as well as working memory.

Effects of Diabetic Ketoacidosis on Visual and Verbal Neurocognitive Function in Young Patients Presenting with New-Onset Type 1 Diabetes.

OBJECTIVE: To evaluate the effects of diabetic ketoacidosis (DKA) on neurocognitive functions in children and adolescents presenting with new-onset type 1 diabetes. METHODS: Newly diagnosed patients were divided into two groups: those with DKA and those without DKA (non-DKA). Following metabolic stabilization, the patients took a mini-mental status exam prior to undergoing a baseline battery of cognitive tests that evaluated visual and verbal cognitive tasks. Follow-up testing was performed 8-12 weeks after diagnosis. Patients completed an IQ test at follow-up. RESULTS: There was no statistical difference between the DKA and non-DKA groups neither in alertness at baseline testing nor in an IQ test at follow-up. The DKA group had significantly lower baseline scores than the non-DKA group for the visual cognitive tasks of design recognition, design memory and the composite visual memory index (VMI). At follow-up, Design Recognition remained statistically lower in the DKA group, but the design memory and the VMI tasks returned to statistical parity between the two groups. No significant differences were found in verbal cognitive tasks at baseline or follow-up between the two groups. Direct correlations were present for the admission CO2 and the visual cognitive tasks of VMI, design memory and design recognition. Direct correlations were also present for admission pH and VMI, design memory and picture memory. CONCLUSION: Pediatric patients presenting with newly diagnosed type 1 diabetes and severe but uncomplicated DKA showed a definite trend for lower cognitive functioning when compared to the age-matched patients without DKA.

The relationship between standardized measures of language and measures of spontaneous speech in children with autism.

This study investigated the relationship between scores on standardized tests (Clinical Evaluation of Language Fundamentals [CELF], Peabody Picture Vocabulary Test-Third Edition [PPVT-III], and Expressive Vocabulary Test) and measures of spontaneous speech (mean length of utterance [MLU], Index of Productive Syntax, and number of different word roots [NDWR]) derived from natural language samples obtained from 44 children with autism between the ages of 4 and 14 years old. The children with autism were impaired across both groups of measures. The two groups of measures were significantly correlated, and specific relationships were found between lexical-semantic measures (NDWR, vocabulary tests, and the CELF lexical-semantic subtests) and grammatical measures (MLU, and CELF grammar subtests), suggesting that both standardized and spontaneous speech measures tap the same underlying linguistic abilities in children with autism. These findings have important implications for clinicians and researchers who depend on these types of language measures for diagnostic purposes, assessment, and investigations of language impairments in autism.