WESTCHESTER, Ill. - Four days' exposure to a REM sleep deprivation procedure reduces cell proliferation in the part of the forebrain that contributes to long-term memory of rats, according to a study published in the February 1 issue of the journal SLEEP.
The study, authored by Dennis McGinty, PhD, of the V.A. Greater Los Angeles Healthcare System, focused on male Sprague-Dawley rats. REM sleep deprivation was achieved by a brief treadmill movement initiated by automatic online detection of REM sleep. A yoked-control (YC) rat was placed in the same treadmill and experienced the identical movement regardless of the stage of the sleep-wake cycle.
According to the results, REM sleep was reduced by 85 percent in REM sleep deprived rats and by 43 percent in YC rats. Cell proliferation was reduced by 63 percent in REM sleep deprived rats compared with YC rats. Across all animals, cell proliferation exhibited a positive correlation with the percentage of REM sleep.
"Several studies have shown that sleep contributes to brain plasticity in general, and to adult neurogenesis, in particular," said Dr. McGinty. "Neurogenesis is a concrete example of brain plasticity, suppression of adult neurogenesis is thought to be important in pathologies such as depression. One current question has to do with the relative contribution of the two sleep states, non-REM and REM, which have very different, even opposite, physiological properties. This study showed that REM sleep has a critical role in facilitating brain plasticity. The study does not exclude an equally important role for non-REM sleep. In other recent work, we have shown that sleep fragmentation can also suppress adult neurogenesis. How sleep affects the molecular mechanisms underlying neurogenesis remains to be explored."
It is recommended that older adults get between seven and eight hours of nightly sleep.
The American Academy of Sleep Medicine (AASM) offers the following tips on how to get a good night's sleep:
- Follow a consistent bedtime routine.
- Establish a relaxing setting at bedtime.
- Get a full night's sleep every night.
- Avoid foods or drinks that contain caffeine, as well as any medicine that has a stimulant, prior to bedtime.
- Do not bring your worries to bed with you.
- Do not go to bed hungry, but don't eat a big meal before bedtime either.
- Avoid any rigorous exercise within six hours of your bedtime.
- Make your bedroom quiet, dark and a little bit cool.
- Get up at the same time every morning.
Those who suspect that they might be suffering a sleep disorder are encouraged to consult with their primary care physician or a sleep specialist.
SLEEP is the official journal of the Associated Professional Sleep Societies, LLC, a joint venture of the AASM and the Sleep Research Society.
SleepEducation.com, a patient education Web site created by the AASM, provides information about various sleep disorders, the forms of treatment available, recent news on the topic of sleep, sleep studies that have been conducted and a listing of sleep facilities.
For a copy of this article, entitled, "Rapid eye movement sleep deprivation contributes to reduction of neurogenesis in the hippocampal dentate gyrus of the adult rat", or to arrange an interview with an AASM spokesperson regarding this study, please contact Jim Arcuri, public relations coordinator, at (708)492-0930, ext. 9317, or firstname.lastname@example.org.