Lifespan EEG Reference Charts Reveal Aperiodic Confounds in Beta-Band Biomarkers Across Neurological and Neuropsychiatric Disorders

The research established the first comprehensive reference charts for beta oscillations based on data from 22,094 individuals aged 1 to 100 years. Beta power exhibited a three-phase trajectory: increasing during childhood and adolescence, peaking around age 50, and declining in later life. Adjusted beta frequency revealed a previously unknown dip during adolescence around ages 12-13 years, consistent across all brain lobes and both sexes. Beta power was reduced across most clinical groups, with schizophrenia being a notable exception, showing lower absolute but increased adjusted beta power. The research demonstrates that aperiodic activity does not merely modify beta measurements but reverses their apparent developmental trajectory, a systematic bias that distorts understanding of beta frequency development and obscures specific oscillatory signatures in clinical disorders.