How many channels are typically recorded during a full PSG?

A typical full polysomnography (PSG) study records around 20 channels. This setup is designed to thoroughly assess various physiological parameters during sleep. The channels usually include EEG (electroencephalogram) traces to monitor brain activity, EOG (electrooculogram) for eye movements, EMG (electromyogram) for muscle activity, along with recordings of airflow, respiratory effort, oxygen saturation, and heart rate.

Having 20 channels allows for comprehensive monitoring of sleep stages, detecting sleep disorders like sleep apnea, and understanding other physiological processes occurring during sleep. The combination of these channels provides a detailed view of the patient's sleep architecture and helps clinicians make informed decisions regarding any potential sleep disorders. Thus, the choice of 20 channels reflects the standard practice in sleep studies, ensuring that all necessary data is collected for a complete assessment.