In our dreams we are turning into some kind of Indiana Jones. We are experiencing numerous adventures, we are turning into celebrated dancer or even into a super hero. But in spite of all adventures, dance performances or nightly flights we are not falling out of the bed. But, why are we not?
Our sleep is divided into different sleeping phases. We hardly move during deep sleep and during REM-sleep. The decreasing muscle-tension is one reason for that. Our muscles are somehow paralyzed only our eyes are rapidly moving during REM-sleep (REM=rapid eye movement). That’s the reason why we are relatively safe during dreaming, because, not everything we are dreaming about is transferred into an actual movement. Except for sleep walkers who mostly wander around during deep sleep and people who suffer under the so-called “REM-sleep-behavior-disorder”, short, RBD. RBD is a sleep disturbance in which people concerned act out the dreamed movements during the REM-phase. This might be a risk of injury, for the people concerned as well as for their bed-neighbors.
Tossing and turning during sleep mainly happens during light sleep. Here, we are awakening but quickly fall asleep again, for example, when we are freezing and are looking for our blanket. When changing the position, our muscles are activated and we shortly awaken. According to studies, this process might repeat up to 10 times per hour. The better your sleeping underlay supports and adapts to your body, the less shifts are necessary, by the way. Subconsciously the dreaming persons realize their local position and adjust to it. That’s why we are able to realize when we are at the edge of the bed.
Small children often sleep in a crib to prevent them from falling out of the bed. Adults on the other hand, seem to have a protective mechanism. With children, this function is not so much pronounced and therefore, they fall out of the bed, once in a while. Similar to the learning effect of walking this process has to be learned.