Which aspect of sleep does a polysomnography primarily record?

Polysomnography primarily records brain waves because it is a comprehensive sleep study that captures the electrical activity of the brain during different sleep stages. This data is crucial for diagnosing various sleep disorders, as the patterns of brain waves can indicate whether a person is in light sleep, deep sleep, or REM sleep. Brain waves are measured using electroencephalography (EEG), which is an integral part of polysomnography. While polysomnography does also record other physiological parameters like muscle activity, heart rate, and sometimes body temperature, its main purpose is to monitor and analyze the brain's activity throughout the sleep cycles. This focus on brain waves makes it possible to assess the overall health and function of a person's sleep architecture, aiding in accurate diagnosis and treatment of sleep-related issues.