Sleep (cont.)
Medical Author:
Melissa Conrad Stöppler, MD
Melissa Conrad Stöppler, MDMelissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology. Medical Editor:
Charles Patrick Davis, MD, PhD
Charles Patrick Davis, MD, PhDDr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications. In this Article
 What are the stages of sleep?There are two general states of sleep: 1) rapid eye movement (REM) sleep, and 2) non-rapid eye movement (NREM) sleep. NREM sleep is further subdivided into stages (see below). 1. REM sleep (rapid-eye movement): REM sleep is unlike any of the other stages of sleep. It was first described in 1953 when sleep researchers noticed a unique pattern of brain waves (signals recorded on an electroencephalogram (EEG), a type of test that measures the electrical impulses within the brain). These brain waves had a fast frequency and low voltage, similar to the brain waves seen in the normal awake state. Other characteristics of REM sleep include complete inactivity of the voluntary muscles in the body, with the exception of the muscles that control eye movements. Rapid eye movements are also observed during REM sleep. People who are awakened during REM sleep often report that they were dreaming at the time. About 20% to 25% of sleep time is REM sleep; in infants it can comprise about 40%. 2. NREM (non-rapid eye movement): NREM sleep has traditionally been considered to be divided into 4 stages. However, new guidelines from the American Academy of Sleep Medicine (AASM) published in 2007 have recharacterized NREM sleep as occurring in 3 stages, according to the pattern of brain electrical activity:
Sleep typically occurs in cycles that range from 90 to 120 minutes in length, with 4-5 cycles occurring during each night's sleep. In the first half of the night, there is a transition from wakefulness into stage N1 sleep, then to stages N2, and N3. Stages N2 and N3 then reappear, followed by the first instance of REM sleep. Cycles of stage N2 and REM sleep alternate with each other for the second half of the night. Disruptions in the entire sleep cycle or in the individual phases are believed to account for the various types of sleep disorders. Patient CommentsViewers share their comments
Sleep - Deprivation Symptoms
Question: Besides lack of sleep, what other symptoms have you experienced with sleep deprivation?
Sleep - Problems Experienced
Question: What sleep problems have you experienced?
Sleep - Treatment
Question: Please discuss any treatments you have tried for your sleep problems.
|
Suggested Reading on Sleep by Our Doctors
-
Related Diseases & Conditions
46 articles-
Hip Bursitis
- Bursitis of the hip results when the fluid-filled sac (bursa) near the hip becomes inflamed due to localized soft tissue trauma or strain. Symptoms include
-
Bed Bugs
- Bed bugs (from the insect family Cimicidae) are small, reddish-brown tick-like insects that feed by sucking the blood of mammals. They are often found
-
Night Sweats
- Night sweats are severe hot flashes that occur at night and result in a drenching sweat. In order to distinguish night sweats that arise from medical causes
-
Anxiety
- Anxiety is a feeling of apprehension and fear characterized by physical symptoms. Anxiety disorders are serious medical illnesses that affect approximately
-
Cystic Fibrosis
- Cystic fibrosis is a disease of the mucus and sweat glands. Cystic fibrosis is an inherited disease. The outcome of the disease leaves the body malnourished,
-
Tension Headache
- A tension headache is a headache previously thought to be caused by contraction of the muscles in the back of the neck, on the scalp, and sometimes in
-
Posttraumatic Stress Disorder
- Post-traumatic stress disorder (PTSD), a psychiatric condition, can develop after any catastrophic life event. Symptoms include nightmares, flashbacks,
-
Restless Leg Syndrome
- Restless leg syndrome (RLS or restless legs syndrome) is a common cause for painful legs that typically eases with motion, and becomes worse and more noticeable
-
Depression
- Depression is an illness that involves the body, mood, and thoughts and affects the way a person eats and sleeps, the way one feels about oneself, and
-
Jet Lag
- Jet lag (desynchonosis) is a temporary disorder that results from travel across time zones. Symptoms include anxiety, constipation, headache, nausea, dehydration,
-
Sleep Apnea
- Sleep apnea is defined as a reduction or cessation of breathing during sleep. The three types of sleep apnea are central apnea, obstructive apnea (OSA),
-
Fatigue
- Fatigue can be described in various ways. Sometimes fatigue is described as feeling a lack of energy and motivation (both mental and physical). The causes
-
Chronic Pain
- Chronic pain is pain (an unpleasant sense of discomfort) that persists or progresses over a long period of time. In contrast to acute pain that arises
-
Marfan Syndrome
- Marfan syndrome is hereditary condition affecting connective tissue. A person with Marfan syndrome may exhibit the following symptoms and characteristics:
-
Chronic Fatigue Syndrome
- Chronic fatigue syndrome is a debilitating and complex disorder characterized by profound fatigue that lasts 6 months or longer, is not improved by bed
-
Grief: Loss of a Loved One
- Grief is the feeling one experiences after a loss (of a friendship, death of loved one, job). Complicated grief refers to grief that lasts for more than
-
Snoring
- Snoring, like all other sounds, is caused by vibrations that cause particles in the air to form sound waves. While we are asleep, turbulent air flow can
-
Insomnia
- Insomnia is the perception or complaint of inadequate or poor-quality sleep because of difficulty falling asleep; waking up frequently during the night
-
Concussion
- Concussion is a short-lived loss of brain function that is due to head trauma. There are two types of concussion, simple and complex. Symptoms of concussion
-
Stress Management Techniques
- Stress may be considered as any physical, chemical, or emotional factor that causes bodily or mental unrest and that may be a factor in disease causation.
-
Teeth Grinding (Bruxism)
- Bruxism is the medical term for teeth grinding. Bruxism may be caused by stress or anxiety and often happens during sleep. Symptoms and signs include jaw
-
Deviated Septum
- A deviate septum is a condition in which the bone and cartilage that divide the nasal cavity of the nose in half (nasal septum) is significantly off center
-
Cluster Headaches
- The term cluster headache is a type of headache that recurs over a period of time. There are episodes that last one to three times a day during a period
-
Autism Spectrum Disorder (In Children and Adults)
- Autism in children and adults is a developmental disorder, characterized by impaired development in communication, social interaction, and behavior. Autism
-
Narcolepsy
- Narcolepsy, a chronic disease of the central nervous system causes have not been fully determined. Some theories include abnormalities in hypocretin neurons
-
Dysthymia
- Dysthymia is a less severe form of chronic depression. Symptoms and signs include insomnia, suicidal thoughts, guilt, empty feeling, loss of energy, helplessness,
-
Sleepwalking
- Sleepwalking is a condition in which an individual walks or does other activities while asleep. Factors associated with sleepwalking include genetic, environmental,
-
Insomnia Treatment (Sleep Aids and Stimulants)
- Insomnia is difficulty in falling or staying asleep, the absence of restful sleep, or poor quality of sleep. Insomnia is a symptom and not a disease. The
-
Depression in Children
- Childhood depression can interfere with social activities, interests, schoolwork and family life. Symptoms and signs include anger, social withdrawal,
- See All Related Diseases & Conditions »
-
Hip Bursitis
-
Medications
36 articles -
Procedures & Tests
3 articles -
Pictures, Images & Quizzes
16 articles -
Doctor's & Expert's Views
29 articles -
Health News
358 articles -
Health Features
56 articles
