1. Elderly with autism: a cognitive profile
Goal: To determine the cognitive profile in older autistic adults.
Results: In the first study we focused on adults aged 53 till 83 years of age. In this study we observed that aging had a smaller impact on fluency in the autism group than in the control group, while aging had a more profound effect on visual memory performance in the autism group. Hence, we provide novel evidence that elderly with an autism diagnosis have subtle neuropsychological deficits, and that the developmental trajectories differ between elderly with and without an autism diagnosis in particular cognitive domains. However, given the small sample size we need to be careful with these conclusions. Therefore, in a much larger follow up study (adults aged 18 till 80 years) we tested whether these findings could be replicated. We observed a different pattern. In general there were hardly any differences between the participants with and without an autism diagnosis in the cognitive performance on various tasks. More over the role of aging did also hardly differ between the two groups. Especially relevant is our finding that we did not find any hints that there might be accelerated cognitive aging in autistic adults. However, we did see some hints of a different aging trajectory on two memory tasks. On these tasks the age-related differences between those with and without an autism diagnoses became smaller as the ‘decrease’ we observed in adults without a diagnoses was not observed in the autistic adults. The current study is a cross-sectional study so we actually can not speak of a decrease or an increase, we could only observe age-related difficulties. This is why we currently run a follow up study were we test the participants twice within a time frame of approximately 2 to 4 years. With this new study we hope to determine a) on which domains we do observe an increase and/or a decrease b) which cognitieve strategies people use c) and which individual differences are prominent to unravel the often observed heterogeneity (i.e., can we determine predictive subgroups?).
Details: In the publication of Geurts & Vissers (2012) in the Journal of Autism and Developmental Disorders (JADD) you can find all details for the first small study. For the second study details can be found in Lever & Geurts (2015) in Autism Research, in Lever et al. (2015) in Journal of Abnormal Psychology, and in Lever et al. (2016) in Developmental Psychopathology. Based on this study we also wrote about symptomatology, comorbidity, and brainaging. For these papers we refer to the publications section of this website.
For a description of this project in Dutch see d’Arc onderzoek.