According to a new review,REM sleep may still warm you up even if the content of your dreams isn't hot.

Warm-blooded creatures with lower body temperatures tend to have longer periods of REM sleep, while those with higher body temperatures don't.

According to Siegel, the association is noteworthy and should be investigated further.

During non-REM sleep, the brain and body temperatures can be too low.

The brain becomes very active during REM and the temperature of the organ goes up. REM sleep usually follows non-REM sleep, which is when the brain and body are not as active.

"REM sleep might be thought of as a thermostatically controlled brain- heating mechanism, which is triggered by the temperature reduction linked to the reduced metabolism and the decrease in energy consumption in non-REM sleep," wrote Siegel.

REM sleep ends after the amount of REM required to raise brain temperature is reached.

Some animals show a change in sleep duration from one season to the next. In winter, non-hibernating animals like reindeer sleep 43 percent more than in the summer. In the winter months, humans in hunter-gatherer societies sleep an hour longer.

REM sleep may be able to protect the animal brain from the cold.

Siegel thinks it's possible since other theories around REM sleep have 888-492-0 888-492-0s.

According to some scientists, non-REM sleep can help clear toxins from the brain, while REM sleep can help enhance memory and learn.

REM sleep is a state of high brain activity similar to waking in most mammals. After toxins are cleaned up in the brain, they will be re-created.

There is no obvious relationship between REM sleep duration and cognitive power, which suggests that its role in learning may be overstated. It takes platypuses up to 8 hours of REM sleep a night. It's difficult to argue that the platypus needs this sleep stage.

The strange creature is a monotreme, a type of middle ground between cold and warm-blooded animals. The platypus would need more REM sleep in order to maintain a functional brain temperature.

REM sleep may have originally evolved as a way for endotherms to keep their brains warm in case of a threat.

dolphins may be an exception that proves the rule as they show no signs of sleep. Uni-hemispheric sleep involves only one side of the brain falling asleep at a time. In exceptional cases, the brain's temperature might not be as easily influenced by sleep because a'space heating' is still going in one part of the room.

Migrating birds do show some signs of REM sleep, even though they do not partake in uni-hemispheric sleep. This stage of sleep involves both sides of the brain, so these types of birds only fall into REM for a short time. It could be very dangerous to fly with an inactive brain.

Fur seals sleep both sides of their brain on land and only one side in the water, so Siegel thinks the uni-hemispheric exception could be tested further.

The idea of REM sleep keeping the motor running for animals like us is complicated by the debate surrounding REM sleep in cold-blooded reptiles, which can't be ruled out.

It is important for animals to sleep to save energy. REM sleep might be a solution to an old problem.

There was a study published.