Cross‐Sectional Evidence for a Decrease in Cognitive Function With Age in Children With Autism Spectrum Disorders?

Abstract

Autism spectrum disorders (ASD) are associated with early disturbances in brain maturation processes and these interferences presumably have their consequences for the progressive emergence of cognitive deficits later in life, as expressed in intelligence profiles. In this study, we addressed the impact of age on cognitive functioning of 6- to 15-year-old children and adolescents with ASD. Intelligence profiles were measured by the Wechsler Intelligence Scale for Children and compared among four consecutive age cohorts (children aged 6.17-8.03 years, 8.04-9.61 years, and 9.68-11.50 years and adolescents aged 11.54-15.85 years) of 237 high-functioning boys with ASD. The results clearly demonstrated that the global intelligence level was lower in children aged 8 years and older, when compared with 6- and 7-year-old children with ASD. This is mostly due to the Freedom From Distractibility factor, suggesting that older children were less able to sustain their attention, they were more distractible, or had more graph motor difficulties. Moreover, an effect of age was also found with respect to the relatively poor performance on the subtest Comprehension when compared with other verbal comprehension subtests, indicating that specifically the impairments in verbal comprehension and social reasoning abilities were more profound in older children when compared with 6- and 7-year-old children with ASD. Findings of this cross-sectional study showed that it is relevant to take age into account when evaluating the impact of cognitive impairments on intelligence in children with ASD, because the impact of these developmental disorders might be different at different ages.

A Discrepancy in Comprehension and Production in Early Language Development in ASD: Is it Clinically Relevant?

“…Taken together, our findings from the comparison of LT and ASD toddlers and the longitudinal data for the ASD group at 30 and 44 months is consistent with previous research reporting significant comprehension-production discrepancy profiles in children with ASD (Barbaro and Dissanayake 2012; Barneveld et al 2014; Ellis Weismer et al 2010; Hudry et al 2010; Kover et al 2013; Luyster et al 2008; Maljaars et al 2012; Seol et al 2014; Volden et al 2011). However, we found a higher percentage of children with ASD who exhibited a discrepant comprehension-production profile in our smaller ASD-LT comparison sample (91%) than our broader longitudinal sample of children with ASD at a mean age of 30 months (62%).…”

“…On the other hand, our longitudinal findings confirm previous cross-sectional results (Seol et al 2014), indicating that the relative comprehension weakness diminishes from toddlerhood through the preschool period. Other cross-sectional studies examining older children, however, have reported discrepant comprehension-production profiles after age six (Barneveld et al 2014; Kover et al 2013). Future longitudinal studies need to tease apart whether the discrepant comprehension-production profile later in development re-emerges or whether those who persist in exhibiting a discrepant comprehension-production profile at 66 months continue to display this profile throughout development.…”

“…Children with autism spectrum disorders (ASD) often present with a discrepant comprehension-production language profile—a relative degree of delay that is more pronounced for comprehension than production (i.e., higher production than comprehension performance) (Barbaro and Dissanayake 2012; Barneveld et al 2014; Charman et al 2003; Ellis Weismer et al 2010; Hudry et al 2010; Kover et al 2013; Loucas et al 2008; Luyster et al 2008; Maljaars et al 2012; Seol et al 2014; Volden et al 2011). More children with ASD show the discrepant comprehension-production profile than typically developing (TD) children or children with other developmental and intellectual disabilities (Barbaro and Dissanayake 2012; Ellis Weismer et al 2010; Maljaars et al 2012; Seol et al 2014).…”

“…These findings were based on statistical comparison of language domains across receptive-expressive subtests/tests (Barbaro and Dissanayake 2012; Barneveld et al 2014; Hudry et al 2010; Kjelgaard and Tager-Flusberg 2001; Kover et al 2013; Luyster et al 2008), analysis of difference/discrepancy scores (Loucas et al 2008; Pickles et al 2014; Volden et al 2011), or visual examination of graphed data for vocabulary (Charman et al 2003; Hudry et al 2010), see Table 1. Other researchers have categorized children according to their language domain profile.…”

Cognitive profile in adults with Asperger syndrome using WAIS-IV: Comparison to typical adults

“…Being a neurodeveloppemental disorder, the impact of AS might be different throughout life, as shown by some cross sectional studies (e.g. Barneveld, Swaab, van Engeland, & de Sonneville, 2014). It is relevant to take age into account when evaluating intelligence in ASD individuals.…”