Spectral and coherence analysis applied to sleep apnea

The various mechanisms that have been proposed to explain sleep apnea in the elderly are examined. Spectral analysis of the electroencephalogram (EEG), not only in the frequency domain using autoregressive algorithms and the fast Fourier transform, but also in the time domain with comb filters and period-amplitude (PA) analysis, is discussed. The PA features, in particular, may provide an improved basis for the coherence function between ventilation and the state-dependent input.<
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