The Sleep Process

Apnea

An  apnea is a reduction or cessation of breathing or airflow during sleep.

Catalepsy

Catalepsy is a condition marked by abrupt attacks of muscular weakness or loss of muscle tone.  It is triggered by emotional stimuli such as laughter, anger or fear.  It is often associated with narcolepsy.

Cpap/Bipap

A CPAP machine maintains a Continuous Positive Airway Pressure to the subject’s airway so that unobstructed breathing becomes possible, reducing and/or preventing apnea.   A Bipap machine (Bilevel Positive Airway Pressure) provides two levels of pressure: Inspiratory Positive Airway Pressure (IPAP) and a lower Expiratory Positive Airway Pressure (EPAP) for easier exhalation.

EEG

An electroencephalogram (EEG) is a recording of the electrical activity of the brain, obtained by attaching sensing electrodes to the head.

Insomnia

Difficulty in initiating or maintaining sleep, or both.

Narcolepsy

A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep.

Night Terrors

A partial awakening from non-REM sleep with extreme fear.

Parasomnias

A term for sleep disorders that involve abnormal and unnatural movements, behaviors, emotions, perceptions, and dreams that occur while falling asleep, sleeping, between sleep stages, or arousal from sleep.

Periodic Limb Movement Disorder

Recurring episodes of repetitive and stereotyped limb movements during sleep.

Polysomnography

Simultaneous measurement of several signals during sleep, for example: brain electrical activity, heart activity, airflow, respiration and oxygen saturation.

Stages of Sleep

Sleep occurs in a fairly regular cycle consisting of four types of non-REM sleep: stage 1 (drowsy sleep), stage 2 (light sleep), stages 3 and 4 (deep sleep), followed by a stage of REM (rapid eye movement) sleep.  Typically there are 4-5 cycles during a night, each cycle lasting about 90 minutes.

Sleep Clinic

A center in which sleep problems or disorders are detected, diagnosed and treated.

Sleep Number Bed

Part of a proprietary adjustable mattress system.  Each sleeper’s best adjustment is characterized by a number from 1 to 100.

Sleep Paralysis

During REM sleep the body is paralyzed.  Sleep paralysis occurs when the brain awakes from a REM state, but the body paralysis persists.

Sleep Walking

Walking while sleeping.  Occurs most frequently during middle childhood and young adolescence

REM Sleep

Stage 5 of the sleep cycle is characterized by Rapid Eye Movement.  Most involuntary muscles are paralyzed.  This stage of sleep has been called ‘a wakened brain in a paralyzed body’.

Restless Legs Syndrome

Restless legs syndrome (RLS) is a disorder characterized by unpleasant feelings of creeping or crawling that causes a strong urge to move the legs.