May 5, 2024

Length of REM Sleep Linked to Body Temperature

According to new research from UCLA, the length of REM sleep is connected to animals body temperature level, with higher body temperatures associated with lower quantities of REM sleep.
Warm-blooded animal groups with lower body temperature levels have more rapid-eye-movement sleep (REM) sleep, while those with higher body temperatures have lower quantities of REM sleep. This is according to new research study from Jerome Siegel, a University of California, Los Angeles (UCLA) teacher who said his study recommends that REM sleep imitates a “thermostatically regulated brain heating system.”

Siegel states the findings suggest a previously unnoticed relationship between body temperature and REM sleep, a duration of sleep when the brain is extremely active. Published just recently in Lancet Neurology, the study was authored by Prof. Siegel, who directs the Center for Sleep Research at the Jane and Terry Semel Institute for Neuroscience and Human Behavior at UCLA.

REM sleep first happens about 90 minutes after falling asleep. Most of your dreaming takes place throughout REM sleep, although some can also happen in non-REM sleep. As you age, less of your time sleeping is invested in REM sleep.

Rapid eye movement first takes place about 90 minutes after going to sleep. Behind closed eyelids, your eyes dart rapidly from side to side. Mixed frequency brain wave activity ends up being closer to that seen in wakefulness. Your breathing ends up being faster and irregular, and your heart rate and blood pressure increase to near waking levels. Many of your dreaming takes place throughout REM sleep, although some can also happen in non-REM sleep. Your arm and leg muscles become briefly paralyzed, which prevents you from acting out your dreams. As you age, less of your time sleeping is spent in REM sleep.

Birds have the highest body temperature of any warm-blooded, or homeotherm, animal group at 41 ° C( 106 ° F) while getting the least REM sleep at 0.7 hours each day. Thats followed by people and other placental mammals (37 ° C/99 ° F), 2 hours of REM sleep), marsupials (35 ° C/95 ° F, 4.4 hours of REM sleep), and monotremes (31 ° C/88 ° F, 7.5 hours of REM sleep).
Brain temperature falls in non-REM sleep and then increases in REM sleep that generally follows. This pattern “allows homeotherm mammals to conserve energy in non-REM sleep without the brain getting so cold that it is unresponsive to danger,” Siegel stated.
The quantity of human beings REM sleep is neither low nor high compared to other homeotherm animals, “weakening some popular views recommending a function for REM sleep in learning or psychological regulation,” he said.
Referral: “Sleep function: an evolutionary perspective” by Jerome M Siegel, PhD, 1 October 2022, The Lancet Neurology.DOI: 10.1016/ S1474-4422( 22 )00210-1.
Siegels research is supported by National Institutes of Health grants (HLB148574 and DA034748) and the Medical Research Service of the Department of Veterans Affairs. He declared no contending interests.