What Is a Sleep Study? Polysomnography Explained
A sleep study, or polysomnography (PSG), is an overnight test that records your brain waves, breathing, oxygen, heart rhythm and movements to diagnose sleep disorders such as sleep apnea.
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A sleep study, formally called polysomnography (PSG), is the reference test for diagnosing sleep disorders. It records what your body does while you sleep so a sleep physician can see problems you can't notice yourself.