ELECTROENCEPHALOGRAPHIC CORRELATES OF PACED BREATHING

MULTICHANNEL EEG, respiration, blood pressure and ECG were recorded du ring paced breathing at five frequencies in 18 subjects in order to el ucidate the effects of paced breathing on power changes in alpha, beta and theta bands, and on rhythmical variability of these parameters. M ean power in the beta band and low-frequency beta power variability (0 .12-0.04 Hz) increased during paced breathing at frequencies of 0.25 a nd 0.20 Hz. The total variability of alpha power in the right parietal and occipital electrodes decreased during paced breathing at 0.1 Hz c ompared with initial rest. The results point to increased cortical exc itability during paced breathing at eupnoeic frequencies and to dimini shed cortical sensitivity to desynchronizing influences during paced b reathing at 0.1 Hz.