Which of the following might be monitored during a sleep study?

Monitoring EEG, EOG, and EMG activity during a sleep study is crucial for understanding the various stages of sleep and muscle activity throughout the night. EEG (electroencephalogram) provides insights into brain wave patterns, allowing technologists to determine different sleep stages, including REM (Rapid Eye Movement) and non-REM sleep. EOG (electrooculogram) tracks eye movements, which are particularly significant during REM sleep when most dreaming occurs. EMG (electromyography) measures muscle activity, especially of the chin, which helps in assessing muscle tone during the different sleep phases.

These measurements are integral to diagnosing sleep disorders such as insomnia, sleep apnea, and narcolepsy. Unlike some of the other options, which may be relevant in different contexts, the monitoring of EEG, EOG, and EMG is a fundamental aspect of polysomnography and is specifically designed to capture the physiological changes that occur during sleep.