Woman having a problem sleepingIn-lab testing is the most accurate method of evaluating sleep conditions. One common test is the polysomnography (PSG) that are usually conducted at a sleep center. This would be performed overnight and is typically used for diagnosing sleep apnea, narcolepsy, and restless leg syndrome.

What Exactly is a Polysomnography?

A polysomnography, also known as a PSG sleep study or test, is performed while you’re fully asleep. A sleep technician or specialist would observe you while you’re sleeping, record the results, and try to determine if you have a sleep disorder.

Specifically, the specialist would measure your brain waves, the activity of your skeletal muscles, heart rate, blood oxygen levels, eye movement, and breathing rate to help in charting your sleep cycles. Observing your sleep cycle and the reactions of your body to the changes in your sleep cycle would help in identifying what’s disrupting your sleep pattern.

PSG would record the shifts of your body between two sleep stages, including rapid eye movement (REM) sleep and non-rapid eye movement (Non-REM) sleep. The latter is composed of two phases — light sleep and deep sleep.

While you’re in REM, you have high brain activity and you’d be dreaming, but only your breathing muscles and eyes would be active. During non-REM sleep, you’ll have slower or reduced brain activity. An individual without a sleep problem is capable of switching between REM and non-REM sleep every 90 minutes. This means that they would experience between four and six sleep cycles every night.

Polysomnography Test Results

Your PSG sleep study score would be reviewed by a sleep specialist in 30-second data epochs and you’ll get your results in seven to 10 days. Your eye movements and brain wave activity would help specialists identify which sleep stages you reached during your test as well as how long each stage and cycle lasted to figure out if you have a sleep disorder.

Your leg movements while sleeping could help identify sleep stages and could be used for diagnosing RBD, or REM sleep behavior disorder, which is a parasomnia characterized by physical activity while in REM sleep where you’re supposed to be still. It likewise helps in determining if you have movement disorders.

Your chin movements during sleep could help in diagnosing bruxism, while your breathing irregularities, blood oxygen levels, and heart rhythms could be used for diagnosing breathing disorders related to sleep. Once your sleep specialist has reviewed your results, they would send it to your doctor so that you could begin proper treatment as soon as possible.