Executive Functions in Young Children with Autism

Abstract

The executive dysfunction hypothesis of autism has received support from most studies of older people with autism; however, studies of young children have produced mixed results. Two studies are presented that compare the performance of preschoolers with autism (mean = 51 months/4.3 years of age) to a control group matched on age, and verbal and nonverbal ability. The first study (n = 18 autism and 17 control) found no group differences in performance on 8 executive function tasks (A not B, Object Retrieval, A not B with Invisible Displacement, 3-Boxes Stationary and Scrambled, 6-Boxes Stationary and Scrambled, and Spatial Reversal), but did find that children with autism initiated fewer joint attention and social interaction behaviors. The second (longitudinal) study of a subset of the children (n = 13 autism and 11 control) from the first study found that neither groups' performance on Spatial Reversal changed significantly over the course of a year. The results of these studies pose a serious challenge to the executive dysfunction hypothesis of autism.

Executive dysfunction in autism☆

“…Deficits in mental flexibility but not in the on-line maintenance and manipulation of information (taken as another executive function), were seen in young children with autism of approximately four years in relation to developmentally disordered as well as normally developing controls. Twelve months later joint attention impairment at the first test was a significant predictor of mental flexibility (assessed by a spatial reversal task) at test two in the autism group only [43].…”

“…functioning [40][41][42][43]. The greatest deficits being seen in the older samples and on a test of mental flexibility.…”

“…Given the complexity of tasks of executive function used with older children and adults, it is not possible to make comparisons using the well-known tasks described above. Using tests developed for nonhuman primates as well as for young children, studies of preschool-aged autistic children have identified a pattern of intact and impaired performance in executive functioning [40][41][42][43]. The greatest deficits being seen in the older samples and on a test of mental flexibility.…”

“…Deficits in mental flexibility but not in the on-line maintenance and manipulation of information (taken as another executive function), were seen in young children with autism of approximately four years in relation to developmentally disordered as well as normally developing controls. Twelve months later joint attention impairment at the first test was a significant predictor of mental flexibility (assessed by a spatial reversal task) at test two in the autism group only [43].The link between joint attention and executive function has been investigated further in studies that have drawn particular parallels between behavioural tasks and neuroanatomical structures. Dawson and colleagues have studied young autistic children in comparison with normal developing children and those with Down syndrome.…”

Social and attention factors during infancy and the later emergence of autism characteristics

“…In typical adults, multiple distributed neuroanatomical systems, primarily associated with the prefrontal cortex, mediate such functions (Kramer & Quitania, 2007;Stuss, 2007). Some researchers have proposed that impairment in the prefrontal cortex is secondary to those found in social-communicative systems in the medial temporal lobe (Dawson et al, 2002;Griffith, Pennington, Wehner, & Rogers, 1999). An alternative account suggests that key characteristics of autism have their origins in early non-social abilities.…”