The developmental trajectory of functional excitation-inhibition balance relates to language abilities in autistic and allistic children.
A jump in brain excitability during late childhood predicts poorer listening skills in both autistic and non-autistic kids.
01Research in Context
What this study did
Hannah et al. (2023) tracked brain excitability in autistic and non-autistic kids. They wanted to see if surges in excitability line up with poor listening skills.
All kids were in late elementary or early teen years. The team used safe lab tools to measure excitability many times over two years.
What they found
Kids who showed a jump in cortical excitability also scored lower on listening tests. This link showed up in both autistic and non-autistic groups.
The study found no fixed 'too much excitation' trait that lives only in autism. Instead, the timing of the surge mattered most.
How this fits with other research
Hua et al. (2024) pooled brain-scan papers and saw autistic youth under-activate key sound areas during listening tasks. Hannah's work adds a 'when' factor: the surge in excitability, not just the baseline level, hurts comprehension.
Fleury et al. (2018) followed the same age range and found autistic kids keep growing in language at the same rate as peers, but they start lower and never close the gap. Hannah's excitability surge may be one reason that gap stays open.
Reichard et al. (2019) showed the same steady growth pattern in younger kids. Together the three studies form a timeline: early vocabulary gaps appear by age four, excitability surges in late childhood, and comprehension scores stay low into the teens.
Why it matters
Watch for developmental windows, not just diagnosis labels. If a client around 10-13 suddenly struggles with listening tasks, check for rapid skill loss rather than blaming 'autism traits.' Build in quiet breaks, slow-rate instructions, or noise-reduction headphones during these growth spurts. Targeting the timing of excitability may help close the stubborn comprehension gap that starts early and lingers.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add a brief listening check after any fast-paced activity block; if accuracy drops, insert a 2-minute quiet reset before continuing.
02At a glance
03Original abstract
Autism is a neurodevelopmental condition that has been related to an overall imbalance between the brain's excitatory (E) and inhibitory (I) systems. Such an EI imbalance can lead to structural and functional cortical deviances and thus alter information processing in the brain, ultimately giving rise to autism traits. However, the developmental trajectory of EI imbalances across childhood and adolescence has not been investigated yet. Therefore, its relationship to autism traits is not well understood. In the present study, we determined a functional measure of the EI balance (f-EIB) from resting-state electrophysiological recordings for a final sample of 92 autistic children from 6 to 17 years of age and 100 allistic (i.e., non-autistic) children matched by age, sex, and nonverbal-IQ. We related the developmental trajectory of f-EIB to behavioral assessments of autism traits as well as language ability. Our results revealed differential EI trajectories for autistic compared to allistic children. Importantly, the developmental trajectory of f-EIB values related to individual language ability. In particular, elevated excitability in late childhood and early adolescence was linked to decreased listening comprehension. Our findings provide evidence against a general EI imbalance in autistic children when correcting for non-verbal IQ. Instead, we show that the developmental trajectory of EI balance shares variance with autism trait development at a specific age range. This is consistent with the proposal that the late development of inhibitory brain activity is a key substrate of autism traits.
Autism research : official journal of the International Society for Autism Research, 2023 · doi:10.1002/aur.2992