Phase amplitude coupling of theta-gamma EEG frequency bands in sleep apnoea

Phase amplitude coupling of neuronal oscillations has been suggested to link with upper brain functions such as cognitive and memory process. It is suggested that cross frequency coupling (CFC) occurred when the amplitude of fast oscillation is modulated by the phase of slow oscillation. In this study, we assess CFC in terms of Modulation Index (MI) of theta, low gamma (LG) and high gamma (HG) in sleep stages N1, N2, N3 and REM of healthy and sleep apnoea patients. The results showed theta phase modulated more the HG band in all sleep stages. Theta-HG coupling was more pronounced in the sleep apnoea as compared to the healthy.