Supplemetal Figure S2

Polysomnography recordings during inhalation of 2.5% CO2 across different sleep stages in a participant. From top to bottom, traces show diaphragm electromyography (EMGdi), electroencephalography (EEG), electrooculography (EOG), nasal airflow (FLOW), end-tidal carbon dioxide (ETCO2), and sleep stage. Although EMGdi, EEG, and airflow varied across sleep stages, ETCO2 and inspired CO2 remained nearly constant throughout the overnight study.