Neuropsychological Correlates of Early Symptoms of Autism

Abstract

Both the medial temporal lobe and dorsolateral prefrontal cortex have been implicated in autism. In the present study, performance on two neuropsychological tasks--one tapping the medial temporal lobe and related limbic structures, and another tapping the dorsolateral prefrontal cortex--was examined in relation to performance on tasks assessing autistic symptoms in young children with autism, and developmentally matched groups of children with Down syndrome or typical development. Autistic symptoms included orienting to social stimuli, immediate and deferred motor imitation, shared attention, responses to emotional stimuli, and symbolic play. Compared with children with Down syndrome and typically developing children, children with autism performed significantly worse on both the medial temporal lobe and dorsolateral prefrontal tasks, and on tasks assessing symptoms domains. For children with autism, the severity of autistic symptoms was strongly and consistently correlated with performance on the medial temporal lobe task, but not the dorsolateral prefrontal task. The hypothesis that autism is related to dysfunction of the medial temporal lobe and related limbic structures, such as the orbital prefrontal cortex, is discussed.

Do Gaze Cues in Complex Scenes Capture and Direct the Attention of High Functioning Adolescents with ASD? Evidence from Eye-tracking

“…These results provide support for suggestions of diminished salience of social stimuli in autism (Dawson et al 1998;Klin et al 2003;Swettenham et al 2003;Chawarska et al 2003). Typically developing participants tended to fixate on the face extremely rapidly and also fixated on the face to a greater degree early in viewing than late in viewing.…”

“…It has been proposed that the salience of social stimuli is diminished in individuals with ASD (Dawson et al 1998;Klin, Jones, Schultz & Volkmar, 2003).…”

Case Study of the Development of an Infant with Autism from Birth to Two Years of Age

“…failed to follow any of the examiner's gazes or points. His performance on this task was at or below the average level obtained in a previous study by preschool children with autism (Dawson, Meltzoff, Osterling, & Rinaldi, 1998) Social Orienting-The ability to orient to social and nonsocial stimuli was assessed by the second author. The stimuli consisted of two social stimuli (clapping hands and calling the child's name) and two nonsocial stimuli (playing a musical jack-in-the-box and shaking a rattle).…”

“…These findings are particularly interesting in light of current theories which emphasize impairments in imitation and frontal lobe functioning as core features of autism (Rogers & Pennington, 1991;Dawson, 1991;Meltzoff & Gopnik, 1993;Smith & Bryson, 1994). An assessment of deferred imitation requiring long term memory for actions was not conducted and would be of interest given the cognitive requirements and brain regions involved in such tests (Dawson, Meltzoff, Osterling & Rinaldi, 1998;Meltzoff, 1995). Moreover, although he was able to perform immediate imitation tasks with objects in a relatively structured, and distraction free testing situation, he failed to engage in social imitative play in less structured situations that entailed social engagement with another person and spontaneous attention to another person's behavior (e.g., during free play with mother).…”

Executive dysfunction in autism☆

“…Although performance of autistic 3-4-year-olds was impaired on tasks associated with ventromedial (VMPFC) and dorsolateral (DLPFC) prefrontal areas, only performance on the former was found to be correlated strongly with joint attention ability [40,41]. At five years, difficulties were observed on delayed response and delayed non-matching to sample tasks, both tasks associated with VMPFC, once non-verbal mental ability had been covaried [40]. Structural equationmodelling indicated that performance on these tasks wasmore strongly associated with joint attention abilities than performance on tasks associated with activation of DLPFC, suggesting that core autism symptoms might be related specifically to VMPFC [40].…”