One of the unique features of neural oscillations is that rhythms of distinct frequencies exhibit specific coupling properties (Canolty & Knight, 2010; Jensen & Colgin, 2007; Young & Eggermont, 2009). Cross‐frequency coupling (CFC), which refers to the statistical relationship between the combination of amplitude and phase of two different frequency bands, is an electrophysiologically derived measure of oscillatory coupling in the brain. Phase‐amplitude coupling (PAC), a type of CFC where the phase of a low‐frequency rhythm modulates the amplitude of a high‐frequency rhythm, is becoming an important indicator of information transmission in the brain (Muthuraman et al., 2020). It constitutes a flexible mechanism for combining information across different temporal scales within local cortical networks and plays a functional role in the execution of cognitive functions (Kikuchi et al., 2017; Malinowska & Boatman‐Reich, 2016; Reinhart & Nguyen, 2019; Seymour et al., 2017; Spyropoulos et al., 2018). Concerning sleep disorders, patients with obstructive sleep apnea had significantly lower theta–gamma PAC in the sensorimotor cortex at all sleep stages (Gouveris et al., 2022). Moreover, one study used PAC and amplitude‐amplitude coupling (AAC) to
