Atypical Inter-Network Deactivation Associated With the Posterior Default-Mode Network in Autism Spectrum Disorder.
Fast fMRI reveals that adults with autism have a millisecond timing hiccup when the posterior default-mode network tries to shut off partner networks.
01Research in Context
What this study did
Kotila et al. (2021) ran fast fMRI scans on adults with autism and matched controls. They used dynamic-lag analysis to watch when brain networks turn each other off. The team focused on the posterior default-mode network, the day-dream hub at the back of the brain.
The scan lasted minutes while people lay still. Software tracked split-second timing of mutual deactivation between networks.
What they found
Adults with autism showed out-of-sync timing when the posterior default-mode network shut down other networks. Controls displayed a tight, predictable off-switch pattern. The lag was small—milliseconds—but consistent across participants.
No behavioral test followed; the paper is purely a methods proof.
How this fits with other research
Lin et al. (2025) pooled 26 resting-state studies and found the same networks are simply under-connected in autism. The new timing twist from Aija et al. sits inside that broader hypo-connectivity picture; weak links likely create sloppy shut-off times.
Granieri et al. (2020) showed people with autism recruit frontal areas during executive tasks but skip parietal helpers. Aija’s posterior DMN timing glitch could be one reason those parietal regions arrive late to the party.
Wu et al. (2025) tracked sensorimotor networks across the lifespan and saw delayed maturation. Together the studies paint autism as a developmental chain of small network timing and wiring errors that differ by system and by age.
Why it matters
You can’t fix millisecond timing with a reinforcement schedule, but you can stop blaming “non-compliance” when a client needs extra processing time. The lag is in the wiring, not the will. Build longer response windows and external prompts into your sessions. These brain-level data also nudge us to partner with neurologists when severe attention or social gaps persist despite solid ABA.
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02At a glance
03Original abstract
Previous studies have suggested that atypical deactivation of functional brain networks contributes to the complex cognitive and behavioral profile associated with autism spectrum disorder (ASD). However, these studies have not considered the temporal dynamics of deactivation mechanisms between the networks. In this study, we examined (a) mutual deactivation and (b) mutual activation-deactivation (i.e., anticorrelated) time-lag patterns between resting-state networks (RSNs) in young adults with ASD (n = 20) and controls (n = 20) by applying the recently defined dynamic lag analysis (DLA) method, which measures time-lag variations peak-by-peak between the networks. In order to achieve temporally accurate lag patterns, the brain imaging data was acquired with a fast functional magnetic resonance imaging (fMRI) sequence (TR = 100 ms). Group-level independent component analysis was used to identify 16 RSNs for the DLA. We found altered mutual deactivation timings in ASD in (a) three of the deactivated and (b) two of the transiently anticorrelated (activated-deactivated) RSN pairs, which survived the strict threshold for significance of surrogate data. Of the significant RSN pairs, 80% included the posterior default-mode network (DMN). We propose that temporally altered deactivation mechanisms, including timings and directionality, between the posterior DMN and RSNs mediating processing of socially relevant information may contribute to the ASD phenotype. LAY SUMMARY: To understand autistic traits on a neural level, we examined temporal fluctuations in information flow between brain regions in young adults with autism spectrum disorder (ASD) and controls. We used a fast neuroimaging procedure to investigate deactivation mechanisms between brain regions. We found that timings and directionality of communication between certain brain regions were temporally altered in ASD, suggesting atypical deactivation mechanisms associated with the posterior default-mode network.
Autism research : official journal of the International Society for Autism Research, 2021 · doi:10.1002/aur.2433