Markery zaburzeń poznawczych w epilepsji widoczne w badaniu EEG spoczynkowego: znaczenie aktywności gamma, fal alfa i połączeń funkcjonalnych mózgu
Resting-state EEG markers of cognitive dysfunction in epilepsy: evidence from gamma power, alpha activity, and functional connectivity
W skrócie
Badacze przeanalizowali badania EEG mózgu u 65 pacjentów z epilepsją, aby znaleźć oznaki zaburzeń pamięci i myślenia. Okazało się, że pacjenci z gorszymi wynikami w testach poznawczych mieli wyższą aktywność fal gamma i niższą aktywność fal alfa, a także zmienione połączenia między obszarami mózgu. Te wyniki pokazują, że badanie EEG może pomóc w wczesnym wykryciu problemów z pamięcią i myśleniem u osób z epilepsją.
Oryginalny abstract (angielski)
PURPOSE: Cognitive dysfunction is a common comorbidity in epilepsy, linked to disrupted neural oscillations and network synchronization. Resting-state electroencephalography (EEG) provides a non-invasive approach to identify electrophysiological biomarkers of cognitive dysfunction. This study examined relationships between resting-state EEG spectral power, functional connectivity, and cognitive performance among people with epilepsy. METHODS: Sixty-five persons with epilepsy (mean age 38.72 ± 1.63 years) underwent eyes-closed resting-state EEG and Montreal Cognitive Assessment (MoCA). Participants were classified into preserved cognition (nPCCD; MoCA ≥ 26, n = 35) and comorbid cognitive dysfunction (PCCD; MoCA < 26, n = 30) groups. Power spectral density (PSD) and band-powers were extracted from clean EEG, and functional connectivity was assessed via magnitude-squared coherence. Pearson correlations assessed associations between MoCA and band-powers, and group comparisons evaluated inter-group differences. RESULTS: Global gamma power negatively correlated with MoCA scores all (r= -0.30, p = 0.01, n = 65) and PCCD group (r= -0.57, p = 0.0003), indicating higher gamma activity with poorer cognition. The nPCCD group exhibited higher global alpha power than the PCCD group [17.48 ± 2.63 vs. 10.83 ± 1.76 µV²/Hz, p = 0.0091], with topographic significance over bilateral temporal and parietal regions (15 channels, p < 0.05). Functional connectivity differed between groups across frequency bands, most prominently in alpha. (p < 0.05). CONCLUSIONS: Resting-state EEG reveals elevated gamma power significantly correlates with poorer cognitive performance across all participants as well as PCCD, and also reduced alpha power, and altered functional connectivity as neurophysiological markers of cognitive dysfunction in epilepsy. Combining spectral and network-level measures may improve characterization, early identification, and targeted management of cognitive comorbidity in epilepsy.