Brief personalized rhythmic auditory stimulation facilitates cognitive and neural processing in ageing

There is growing interest in non-invasive brain stimulation (NIBS) as a safe and practical method to support cognitive function during ageing. NIBS using rhythmic sensory stimuli entrains brain oscillations and synchronizes functional networks, but the choice of NIBS frequency to enhance performance in cognitive tasks remains unclear. We adopt a network neuroscience approach to NIBS, linking network connectivity, EEG oscillatory frequencies and behavioural performance to test the effects of personalized rhythmic auditory stimulation (RAS) on an inhibitory control task (Simon task) in older adults aged 60-75 years. Simon task trials were preceded by ≈1.7-3.2 s of personalized RAS (clicks) at each individual's theta oscillation frequency (fθ), a slightly faster variant (fθ+), a fixed low-frequency control at 2 Hz (f2Hz) or a non-rhythmic control (NR). Reaction times (RTs) after personalized stimulation were faster than f2Hz and NR, with stronger brain entrainment to rhythmic stimulation linked to faster RTs. Task-related EEG signals showed enhanced attentional processes and more efficient cortical responses following the personalized stimulation. Individuals with lower baseline performance had the greatest benefits. The findings suggest personalized RAS enhances cognitive performance in ageing and provides a cost-effective neurorehabilitation approach to mitigate age-related cognitive decline.