Depression and sleep disorders are inextricably linked. Many people who suffer from depression experience some kind of sleep disorder, either sleeping too much or too little. Others with depression find themselves exhausted even after a full night’s sleep. These people usually are experiencing abnormal REM sleep, a common complication of depression.
What Is REM Sleep?
REM (or rapid-eye movement) sleep is the fifth stage of sleep. Stage 1 involves drowsiness, Stage 2 is light sleep, and Stages 3 and 4 are deep sleep. Stage 5, REM sleep, is categorized by frequent quick movements of the eyes beneath the eyelids. Dreams occur during REM sleep.
During REM sleep, the brain is particularly active and the body’s large limbs are paralyzed. Many scientists believe that the temporary paralysis is the body’s way of ensuring that people don’t act out their dreams during REM sleep.
Depression and Sleep
People with depression are often plagued by sleep problems. They may have trouble falling asleep because they can’t stop worrying or thinking unpleasant thoughts. They may wake up intermittently during the night and have trouble sleeping in the morning. However, one of the most serious problems with depression and sleep has to do with the stages of sleep, particularly REM sleep.
Normally, a person cycles through the stages of sleep several times each night. In people with depression, the cycles are disorganized. People with depression often lapse into REM sleep quickly after falling asleep, shortening or completely bypassing the other stages. They stay in REM sleep for longer periods of time than their non-depressed counterparts, during which brain activity is often more intense.
Depression and sleep changes are problematic for a few reasons. Because REM sleep is associated with emotional memory, people with depression may be plagued with an overabundance of unpleasant dreams. Frequent bad dreams contribute to restlessness and insomnia in some people. Also, the combination of overactive REM sleep and insomnia can lead to a host of health issues. Short-term side effects may include:
- Daytime drowsiness
- Impaired memory function
- Tension headaches.
Chronic sleep deprivation can lead to serious health issues, such as diabetes and heart disease.
Depression REM sleep disorder has a strong genetic link and is common among first-degree relatives. Many people whose depression has gone into remission still experience REM sleep disorders. Some studies indicate that REM sleep disorder may actually contribute to the onset of depression.
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