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This study examined memory functions in individuals with autism. Based on previous evidence of executive function (EF) deficits, we hypothesized that subjects with autism would demonstrate a pattern of intact and impaired memory functions similar to that found in other groups with EF deficits, such as patients with frontal lobe pathology. We compared the performance of high-functioning children and adolescents with autism (n = 19) and clinical comparison subjects (n = 19) matched on sex, CA, and VIQ on measures of memory and EF. The group with autism performed significantly worse than comparison subjects on measures of temporal order memory, source memory, supraspan free recall, working memory, and EF, but not on short- and long-term recognition, cued recall, or new learning ability, consistent with the predictions of the EF theory. The cognitive measures were significantly more intercorrelated in the autism group than the comparison group, consistent with a limit in central cognition.

Objective To examine prospectively the emergence of behavioral signs of autism in the first years of life in infants at low and high risk for autism. Method A prospective longitudinal design was used to compare 25 infants later diagnosed with an autism spectrum disorder (ASD) with 25 gender-matched low-risk children later determined to have typical development. Participants were evaluated at 6, 12, 18, 24, and 36 months of age. Frequencies of gaze to faces, social smiles, and directed vocalizations were coded from video and rated by examiners. Results The frequency of gaze to faces, shared smiles, and vocalizations to others were highly comparable between groups at 6 months of age, but significantly declining trajectories over time were apparent in the group later diagnosed with ASD. Group differences were significant by 12 months of age on most variables. Although repeated evaluation documented loss of skills in most infants with ASD, most parents did not report a regression in their child’s development. Conclusions These results suggest that behavioral signs of autism are not present at birth, as once suggested by Kanner, but emerge over time through a process of diminishment of key social communication behaviors. More children may present with a regressive course than previously thought, but parent report methods do not capture this phenomenon well. Implications for onset classification systems and clinical screening are also discussed.

Deficits specific to the syndrome of infantile autism appear in imitation, emotion sharing, theory of mind, pragmatics of communication, and symbolic play. Current competing theories of Hobson and of Baron-Cohen, Frith, and associates account for some, but not all, of these specific deficits. The present article suggests that early social capacities involving imitation, emotion sharing, and theory of mind are primarily and specifically deficient in autism. Further, these three capacities involve forming and coordinating social representations of self and other at increasingly complex levels via representational processes that extract patterns of similarity between self and other. Stern's theory of interpersonal development is offered as a continuous model for understanding the development and deficits of the autistic child and as a means for integrating competing theories about the primary deficits in autism. Finally, the article suggests a neuropsychological model of interpersonal coordination involving prefrontal cortex and executive function capacities that is consistent with the social deficits observed in autism.

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A study was designed to test 2 alternative hypotheses--a symbolic hypothesis and an executive function hypotheses--for the imitation and pantomime deficits found in previous studies of autism. The subjects were 17 adolescent high-functioning subjects with autism spectrum disorders and 15 clinical comparison subjects who were matched on chronological age and verbal IQ. Meaning and sequence were manipulated in facial and manual imitation tasks. Sequence was manipulated in the pantomime and control tasks. Recognition memory and motor control tasks were matched to the experimental tasks. The results provided no support for the symbolic deficit hypothesis; meaning aided rather than hindered the performance of the group with autism. Partial support for the executive deficit hypothesis was found. There were no group differences on motor control tasks, and few on the memory control tasks, arguing against deficits in motor initiation, basic motor coordination, or visual recognition memory.

The presence of maladaptive behaviors in young people with autism spectrum disorder (ASD) can significantly limit engagement in treatment programs, as well as compromise future educational and vocational opportunities. This study aimed to explore whether the Early Start Denver Model (ESDM) treatment approach reduced maladaptive behaviors in preschool-aged children with ASD in a community-based long day care setting. The level of maladaptive behavior of 38 children with ASD was rated using an observation-based measure on three occasions during the intervention: on entry, 12 weeks post-entry, and on exit (post-intervention) over an average treatment duration of 11.8 months. Significant reductions were found in children’s maladaptive behaviors over the course of the intervention, with 68% of children showing a treatment response by 12 weeks and 79% on exit. This change was accompanied by improvement in children’s overall developmental level as assessed by the Mullen scales of early learning, but not by significant changes on the Vineland Adaptive Behavior Scales-II or Social Communication Questionnaire. Replication with a larger sample, control conditions, and additional measures of maladaptive behavior is necessary in order to determine the specific factors underlying these improvements; however, the findings of the present study suggest that the ESDM program may be effective in improving not only core developmental domains, but also decreasing maladaptive behaviors in preschool-aged children with ASD.

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