YNIMG Journal 2026 Journal Article
The individual alpha bandwidth: A trait-like neural marker associated with sensory processing and executive function
- Zeliang Jiang
- Pan Zhang
- Hanlin Wang
- Wenxiao Zhong
- Xingwei An
- Zhijie Zhang
Alpha oscillations are a fundamental rhythm of human brain activity, yet most studies have emphasized the peak alpha frequency (IAF) while overlooking the width of the alpha band. Here, we examined the individual alpha bandwidth (IAB) as a complementary marker across four EEG datasets. Using a unified preprocessing pipeline, we assessed its reliability and functional relevance. Test-retest analyses showed good-to-excellent reliability, supporting its trait-like stability. Importantly, IAB estimated with the Savitzky-Golay filter (SGF) method-but not with FOOOF or amplitude-difference-was significantly related to sensory and cognitive processes, whereas IAF showed no such associations. In perception, wider parieto-occipital IAB during eyes-closed rest was associated with larger P2 amplitudes in visual and auditory evoked potentials. In cognition, wider parieto-occipital IAB during eyes-open rest was linked to smaller flanker interference effects and enhanced N450 amplitudes. Mediation analysis further revealed a significant indirect effect of N450 on the IAB-inhibitory control relationship, whereas the direct effect was not significant. These findings suggest that IAB reflects both perceptual and executive processes, but its functional relevance is constrained by methodological and experimental factors. Specifically, associations were method-dependent (emerging only with SGF), state-dependent (perception during eyes-closed rest, cognition during eyes-open rest), and in the cognitive domain, also frequency-window dependent (significant only within 6-14 Hz). Overall, this study establishes IAB as a reliable neural marker of individual differences in sensory and executive function while underscoring key methodological considerations for future research.