Decreased Cortical Thickness in the Anterior Cingulate Cortex in Adults with Autism.
High-functioning adults with autism have a measurably thinner right caudal ACC — a solid biological talking point for BCBAs.
01Research in Context
What this study did
Laidi et al. (2019) scanned high-functioning adults with autism and matched controls. They used MRI to measure cortical thickness across the whole brain.
The team ran the same test twice: once in a discovery sample and again in a new replication sample. This double-check makes the finding harder to dismiss.
What they found
Adults with autism had a thinner right caudal anterior cingulate cortex (ACC) than non-autistic adults. The result showed up in both samples.
The ACC helps us shift attention, monitor errors, and feel pain. A thinner sheet here may explain some social-cognitive quirks seen in autism.
How this fits with other research
Marcell et al. (1988) used older CT scans and saw no brain-shape differences in autistic adults. Laidi et al. (2019) used sharper MRI and did find a difference. Better tools, clearer picture — the new study supersedes the old null result.
Perihan et al. (2020) pooled 23 trials showing CBT eases anxiety in high-functioning kids with autism. Charles shows a possible brain marker in similar high-functioning adults. Together they hint that anxiety treatments and brain markers may track the same "high-functioning" subgroup.
Sun et al. (2023) found reduced pupil oscillation during face tasks in autistic adults. Charles found thinner ACC. Both papers flag quiet biological signals in the same population, giving you more than one window to discuss neurology with families.
Why it matters
You now have a concrete, MRI-backed fact: the right caudal ACC is thinner in high-functioning adults with autism. Mention it when medical providers or parents ask, "Is there real brain evidence?" It also reminds us that attention and error-monitoring struggles may have a structural base, so give clients extra response time and clear feedback cues.
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02At a glance
03Original abstract
Autism spectrum disorder (ASD) is a developmental disorder underdiagnosed in adults. To date, no consistent evidence of alterations in brain structure has been reported in adults with ASD and few studies were conducted at that age. We analyzed structural magnetic resonance imaging data from 167 high functioning adults with ASD and 195 controls. We ran our analyses on a discovery (n = 301) and a replication sample (n = 61). The right caudal anterior cingulate cortical thickness was significantly thinner in adults with ASD compared to controls in both the discovery and the replication sample. Our work underlines the relevance of studying the brain anatomy of an adult ASD population.
Journal of autism and developmental disorders, 2019 · doi:10.1371/journal.pone.0151879