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bioRxiv · 10.64898/2026.07.22.739645

Aperiodic EEG activity is a domain-specific marker of attentional aging in neurotypical adults

Cazares, C.·Rigby, A.·Kang, L.·Getzmann, S.·Arnau, S.·Wascher, E.·Voytek, B.
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Abstract

Aperiodic neural activity has been reliably shown to be reduced among older adults, and these reductions are associated with age-related cognitive decline. These results suggest that aperiodic activity, as measured by the spectral exponent, might be a viable electrophysiological biomarker for cognitive aging. However, this has not been tested longitudinally, within participants, during normal aging. Here, we used a longitudinal cohort to test whether changes in aperiodic activity between two sessions, approximately 5 years apart, track behavioral change across two domains: sustained attention (Psychomotor Vigilance Test) and executive function (modified Simon task). We found that aperiodic activity declined within individuals after the interval, independent of age at baseline. This within-person change tracked concurrent changes in reaction times during visual attention but was not associated with changes in any Simon task measure. Within a resampling framework, the aperiodic-PVT association was stable across cohort resamples and independently fitted partitions, though it was not confirmed in a small, frozen held-out set. These findings suggest the longitudinal decline in aperiodic activity specifically tracks sustained-attention processing speed rather than general cognitive aging, supporting its potential as a domain-specific biomarker of attentional aging in neurotypical populations.

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Cazares, C., Rigby, A., Kang, L., Getzmann, S., Arnau, S., Wascher, E., Voytek, B.. 2026-07-27. Aperiodic EEG activity is a domain-specific marker of attentional aging in neurotypical adults. https://doi.org/10.64898/2026.07.22.739645

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