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bioRxiv · 10.1101/2025.03.28.645908

Cortical functional connectivity across the adult lifespan and its relation to sensorimotor integration

Ruuskanen, S.·Avendano-Diaz, J. C.·Liljeström, M.·Parkkonen, L.
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Abstract

The operation of the human brain relies on functional networks enabled by inter-areal oscillatory synchronization between neuronal populations. Although disruptions in this functional connectivity are associated with brain disorders, evidence on its healthy age-dependent variation and behavioral relevance remains limited. Utilizing magnetoencephalography (MEG) recordings from 576 adults aged 18-87 years, we investigated the evolution of resting-state functional connectivity (rs-FC) across the healthy adult lifespan. We observed age-related, frequency-specific changes in widespread cortical networks. Alpha-band (8-13 Hz) rs-FC decreased, while delta (1-4 Hz), theta (4-8 Hz), and gamma-band (40-90 Hz) rs-FC increased with age. Beta-band (13-30 Hz) rs-FC followed a non-linear trajectory, peaking in middle age. The global delta, theta, alpha, and beta-band patterns differed from concurrent changes in oscillatory power, underscoring their dissociable contributions. Notably, reduced beta-band rs-FC was associated with increased sensorimotor attenuation, indicating that changes in rs-FC are behaviorally relevant for sensorimotor function. These findings advance our understanding of healthy brain aging and highlight a link between resting-state brain activity and sensorimotor integration. Key pointsO_LIFunctional connectivity is altered across the healthy adult lifespan in a frequency-dependent manner C_LIO_LIChanges in source power do not explain global functional connectivity trajectories C_LIO_LIBeta-band connectivity at rest is associated with sensorimotor attenuation independent of age-related effects C_LI

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Ruuskanen, S., Avendano-Diaz, J. C., Liljeström, M., Parkkonen, L.. 2025-03-29. Cortical functional connectivity across the adult lifespan and its relation to sensorimotor integration. https://doi.org/10.1101/2025.03.28.645908

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