Quantitative EEG fingerprints: Spatiotemporal stability in interhemispheric and interannual coherence

Abstract

The aim of our study is to examine the persistence of EEG coherence in the fundamental waves—delta, theta, alpha, and beta—both across spatial domains (within the brain, interhemispheric) and over extended periods (interannual). The long-term stability of a specific EEG wave coherence suggests its potential as a neural fingerprint. A total of 28 participants were included in the intrahemispheric-interannual FFT coherence analysis, comparing EEG data collected years apart. The average interannual interval between the first and second EEG recordings was 7.11 ± 4.56 years, with a range from 1.88 to 19.19 years. The combined data from the two EEG sessions shared 62.7 % of their variance, underscoring significant overlap in their information content. The interannual canonical correlation between the first and second EEGs was 0.792, indicating a strong relationship over time. Overall, alpha coherence, particularly in the frontal lobe, showed marked long-term stability, suggesting it as a strong candidate for an EEG fingerprint. Notably, when comparing fundamental wave coherences in the occipital lobe between the first and second EEGs, only the beta coherence exhibited a remarkable correlation over the years.