Jack Li suffers from obstructive sleep apnea. With the aid of CPAP, he can sleep soundly, reports New Jersey Monthly.

While they talk, Kelley adheres the wires to different parts of Li’s body: six on his scalp to measure brain waves (EEG); two on his jawline and four on his legs to measure muscle movement (EMG); two next to his eyes to measure eye movement (EOG); and two on his torso to track cardiac activity (ECG). She attaches a microphone to his throat to detect vibrations from snoring and a pulse oximeter to one of his fingertips to measure oxygen levels. Next, Kelley wraps two adjustable belts around Li’s chest and stomach to measure respiration. Finally, she covers his nostrils with a breathing apparatus that delivers continuous positive airway pressure, or CPAP.