Sleep Disorder Glossary

Snoring: Sounds made during sleep caused by breathing vibrations in the pharynx. In the diagnosis of obstructive sleep apnea, snoring volume and frequency of occurrence often correlate with the severity of the condition. Snoring noise is recorded in both diagnostic sleep studies and CPAP titration studies.

Sleep apnea: An “apnea” is when breathing stop for 10+ seconds during sleep. There are two basic types of sleep apnea: Obstructive apnea is caused by a closure of the air passage despite efforts to breathe, and central apnea is a lack of effort to breathe. Obstructive sleep apnea is by far the most common type.

Insomnia: Difficulty with falling asleep or staying asleep.

Restless leg syndrome: The sleep disorder characterized by tingling, creeping, crawling, or aching sensation in the legs that tend to occur when an individual is not moving. There is an almost irresistible urge to move the legs that relieve the sensations. Inability to remain at rest can result in severe sleep disturbance.

Gastroesophageal Reflux (GERD): The flow of stomach acid upwards into the esophagus, which can cause arousals and disrupt sleep.

Narcolepsy: This sleep disorder is characterized by excessive sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations, and an abnormal tendency to pass directly into REM sleep from wakefulness. It was recently found to be caused by an abnormal gene in the brain.

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