Association between electroencephalogram alpha-band oscillations and executive and processing functions in patients with cerebral small vessel diseases.

Electroencephalogram (EEG) alpha-band oscillations may reflect executive and processing function in patients with cerebral small vessel disease (CSVD). We aimed to assess such association and its relationship with CSVD severity, and to identify specific alpha-band parameters and the cut-off values for cognitive screening. We analysed the dispersion of amplitude-frequency characteristics of EEG alpha-band and different alpha-band parameters (PFα , ΔPFα , PPα , NCL) in different brain locations. We also assessed patients' executive and processing functions using verbal fluency test (VFT) and color trails test (CTT), and CSVD severity using total burden and Fazekas scores. 129 patients were recruited in the study. After adjusting for age, gender and education, PFα(F3), PFα(F4) and NCL were significantly associated with VFT-composite performance (0.05). CTT-1 time and error were associated with PFα(F3), PFα(F4), ΔPFα(O1;F3) and CSVD severity (0.05), whereas CTT-2 time was only associated with CSVD severity. Moreover, the correlations between alpha-band oscillations and cognitive function were higher in low than in high disease-severity group (ρ: -0.58 vs. -0.38, 0.05). The AUC of selected alpha-band parameters were higher than 0.8 for VFT and CTT. Specific alpha-band parameters in the frontal lobe were identified to correspond to executive and processing function. Assessing EEG alpha-band oscillations may assist in screening cognitive impairment.