Why we don’t fall out of bed when we’re sleeping – 01/22/2023 – Equilibrium

Even if you’re one of those who crash the bed and sleep like a log until the next morning, everyone knows that both the mind and body remain active while we sleep.

Not only do we dream, we snore, we talk, we laugh, we scream, we turn, we snuggle, and we stretch—and we even bang and kick.

But whether you sleep in a camp bed that’s less than 65 cm wide or the 200 cm super king bed, you’re likely to wake up where you slept, no matter how restless your night.

Why then do we not fall out of bed?

“It’s fascinating because we think that when we sleep we are completely disconnected from our surroundings, but no: if someone nearby screams, you wake up”, explains Russell Foster, professor at the University of Oxford, UK, to the BBC’s Crowd Science program. .

“Our bodies continue to collect information through our receptors.”

And there is a sense that definitely does not fall asleep.

“It’s almost like a sixth sense. It tends not to be as good when you’re a kid — that’s why some fall out of bed — but it gets better with age.”

So we don’t “lose our senses” when we fall asleep, particularly the sleep that keeps us from waking up dazed—and maybe even bruised—on the floor.

Sixth Sense?

In popular culture, the sixth sense is associated with extrasensory perception, clairvoyance, premonition, intuition, the ability to communicate with a world inhabited by souls and ghosts.

But scientists like Foster mean something less esoteric.

It’s called proprioception, and experts identified this ability more than a century ago.

Pioneering studies on it were carried out in the 19th century by some of the great names in neuroscience: the Frenchman Claude Bernard, “one of the greatest of all scientists”, according to the historian of science I. Bernard Cohen; the Scottish anatomist Charles Bell, whose work Idea of ​​a New Anatomy of the Brain (1811) has been called the “Magna Carta of neurology”; and Charles Sherrington, who won the 1932 Nobel Prize in Physiology/Medicine and who coined the term proprioception.

What was not clearly known until the second decade of this millennium is how much we depend on it.

Want to see proprioception in action?

Close your eyes and then touch the tip of your left elbow with your right index finger.

Did you find it easy? How did you do it?

Somehow you knew where your fingertip was and you also knew the position of your left elbow.

Also, you could describe your entire body posture without having to see it.

This is proprioception: the awareness we have of where each part of our body is in space.

Proprioception is possible thanks to neurophysiological signals from receptors in our muscles, tendons, joints and skin, which inform the brain about muscle length and elongation, joint rotation, local changes and skin flexion.

It lets us know which direction our joints are moving, makes us aware of our posture and balance.

It’s the sense that, for example, helps you regain balance when you lose it.

Although in this case there is another system that also plays an important role.

Imagine that you are blindfolded, and I lean you forward slowly.

You will immediately feel that your body’s position was changing with respect to gravity.

This is due to the fluid-filled vestibular system in the inner ear, which helps us maintain balance. This system also provides our experience of acceleration through space and is linked to the eyes.

But those don’t really help with not falling out of bed, as they are closed when we sleep, so we won’t lose our way.

Let’s go back to proprioception, quoting an article published on the academic news site The Conversation.

“(Proprioception) is a key component of our ‘global positioning system’, which is essential in our daily lives because we need to know where we are in order to move somewhere”, says an excerpt from the article, authored by four academics.

“Proprioception allows us to determine the position, speed and direction of each part of the body, whether we see it or not, and thus allows the brain to guide our movements.”

Thanks to her, when we are sleeping, we can move freely, but without going beyond the confines of the bed.

This text was originally published here