Parallel Age-Related Cognitive Effects in Autism: A Cross-Sectional Replication Study

Abstract

Findings on age-related effects on cognition in autism spectrum conditions (ASC) in adulthood are ambiguous across studies. As these studies substantially differ in their methodology, replication studies are needed. In this replication study we used frequentist and Bayesian analyses to investigate the hypothesis that in autistic adults compared to non-autistic adults we see mostly parallel, but also protective age-related cognitive effects. Participants were 88 autistic adults, and 88 non-autistic matched comparisons (age range: 30-89 years). Cognitive measures were administered on the following six domains: verbal memory, visual memory, working memory, Theory of Mind (ToM), verbal fluency, and processing speed, and self-reported cognitive failures. We observed that non-autistic adults outperformed autistic adults on ToM, verbal fluency, and verbal memory, but only the first two were confirmed with Bayesian replication analyses. Also, more cognitive failures were reported by autistic adults. No interactions between group and age were observed, suggesting a parallel age-related effect on all cognitive domains. In sum, we replicated earlier observed difficulties in ToM and verbal fluency which seem to persist at older age. Also, we replicate the previously reported parallel age-related cognitive patterns, but found no evidence for protective age-related patterns.

Prepotent Response Inhibition in Autism: Not An Inhibitory Deficit?

“…As this is an oftenobserved characteristic of autistic children and young autistic adults when performing experimental tasks, (e.g., Pirrone et al, 2020) it could be that autistic adults diverge from this strategy when growing older and/or that the strategy of the non-autistic adults becomes more cautious, and thus more similar to the "autistic" strategy ("the aging analogy" by Bowler et al, 2014). This is consistent with research on other cognitive domains (e.g., verbal memory, fluency, and processing speed) indicating similar age-related effects in autistic and non-autistic adults ("parallel aging"; e.g., Davids et al, 2016;Lever & Geurts, 2016;Torenvliet et al, 2021;Tse et al, 2019). Depending on the timing of these age-related changes, task strategy could also have shifted before the age of 20 (i.e., the youngest in our sample).…”

“…Based on previous research, we expected no age-related differentiation in the proposed components of inhibitory performance. We also did not expect age-related differences for autistic and non-autistic adults, given that the majority of findings in other cognitive domains suggest a parallel development (e.g., Torenvliet et al, 2021;Tse et al, 2019). Exploratorily, we investigated the role of ADHD-symptoms in both autisticand non-autistic individuals.…”

A Longitudinal Study on Cognitive Aging in Autism

“…The current study investigated longitudinal cognitive aging in a sample of autistic (n=128) and non-autistic adults (n=112) between 24 and 85 years, extending our previous crosssectional work (Lever & Geurts, 2016;Torenvliet et al, 2021). A comprehensive cognitive test battery (k=15) was administered in three waves in two, overlapping, cohorts.…”

One Size Does Not Fit All: An Individualized Approach to Understand Heterogeneous Cognitive Performance in Autistic Adults

“…All measures were considered to have sufficient psychometric properties and have been previously used in aging as well as autism research. These cognitive measures were also described in Torenvliet et al, (2021).…”

“…Also, higher rates of self-reported cognitive failures have been observed in autistic adults compared to non-autistic adults (e.g., Lever & Geurts 2016). However, those studies objectively measuring cognition, mostly report parallel (i.e., similar) age-related cognitive effects between those with and without autism (Torenvliet et al, 2021;Tse et al, 2019, but see Powell et al, 2017. Given the aforementioned increased incidence of age-related disease, and the cognitive heterogeneity that is known to exist in autism, group-based comparisons on objective cognitive measures might overlook individuals with autism that are particularly vulnerable for cognitive decline.…”