Chronic use of alcohol can disrupt a person's sleep months or even years after a person stops drinking, according to researchers from Boston University School of Medicine.
The researchers say chronic alcohol use can disrupt cells in an area of the brain stem involved in regulating many aspects of sleep, Boston Magazine reports.
As a result of prolonged exposure to alcohol, the activity that excite neurons in the brain increases, while at the same time decreasing the activity of a chemical that inhibits activity of these neurons. This causes over-activity of brain chemicals, and leads to a disruption in the normal sleep cycle, the researchers write in Behavioral Brain Research.
Lead author Subimal Datta says more research is needed to identify exactly how these brain changes are occurring, and to create medications to treat alcohol-related sleep disorders. "Identifying the specific mechanisms that lead to change in brain activity will allow us to develop targeted medications, which could help treat people suffering from sleep issues related to alcohol use disorders," Datta said in a news release.
A study published last year found drinking alcohol may help a person fall asleep, and increase deep sleep during the first half of the night, but can disrupt sleep during the second half.
Researchers reviewed 20 previously published studies on alcohol and sleep. They found alcohol reduced the time it takes people to fall asleep, and helped them to sleep more deeply during the first half of the night, no matter how much they consumed.
During the second half of the night, sleep disruption, or waking after falling asleep, increased. Having at least two drinks reduced overall rapid eye movement (REM) sleep. Dreaming occurs during REM sleep, and is thought to be important for memory.