Brain anatomy and molecular signaling predict neurophysiological dynamics across the lifespan

Neural activity emerges from interactions between local cellular architecture, neuromodulatory systems, and large-scale cortical networks. Yet it remains unclear how this multiscale biological context constrains electrophysiological dynamics in humans and how this changes across the lifespan. We combined resting-state magnetoencephalography (MEG) from 350 adults (18-88 years) with cortical maps reflecting cytoarchitecture, myelination, metabolism, gene expression, and neurotransmitter receptors in a multivariate prediction framework. Specific markers explained most regional variance in MEG power spectra and temporal autocorrelation, similarly for both measures, revealing frequency- and timescale-specific signatures that followed canonical spectral boundaries. Age-related MEG patterns spatially aligned with markers of neuroinflammation, monoaminergic-cholinergic signaling, cortical development and myelination, and cerebrovascular organization. This work identifies key components of an anatomical and molecular scaffold and their relative importance for neural activity across the lifespan, informing future experimental perturbations and generative models.