DISTINCT ALPHA OSCILLATORY AND APERIODIC EEG PROFILES IN WILLIAMS AND DOWN SYNDROMES

Previous work reported sparse evidence of altered brain activity in individuals with Williams (WS) and Down (WS) syndromes. Here, we used EEG to record resting-state brain activity in eyes-closed (EC) and eyes-open (EO) conditions in individuals with WS, individuals with DS, mental age-matched TD children and TD adults.
Individuals with WS exhibited lower individual alpha peak frequency (IAF) and lower alpha power than individuals with DS and TD adults. Individuals with WS exhibited no difference in IAF compared to TD children, but their alpha power was lower than that of TD children in EC. Individuals with DS exhibited higher IAF and alpha power than individuals with WS, but no differences in IAF or alpha power compared to TD children or adults.
Individuals with WS exhibited flatter slope and lower offset of the aperiodic component than TD children. In EO, individuals with WS exhibited no difference in slope or offset compared to individuals with DS or TD adults. In EC, individuals with WS exhibited a flatter slope than individuals with DS and a higher offset than TD adults. Individuals with DS exhibited a flatter slope and a lower offset than TD adults in EO, and a steeper slope and higher offset than TD adults in EC. Individuals with DS exhibited a steeper slope and a higher offset than TD adults, but no difference compared to TD children.
Our findings of distinct alpha oscillations and aperiodic EEG profiles in DS and WS provide new evidence of gene-specific effects on resting-state brain activity.