What is the reason behind the need to “fall” asleep rather than choosing to be asleep?

Question

What is the reason behind the need to “fall” asleep rather than choosing to be asleep?

In: 252

Answer 1

Basically because we weren’t designed to be perfect humans in current day.

But evolved over millions of years.

It started with bacteria that had biological clocks to regulate their metabolism.

And throughout evolution to more complex life forms and eventually mammals and humans, more and more complex systems were added on to the body, and later to the primitive brains of amphibian like animals etc.

So sleeps works like it does for us; because it’s a barely working amalgamation of various time keeping and resting-maintenance systems that came about by random chance and were good enough to make our far away ancestors reproduce.

Additionally having the capability to consciously fall asleep and that not be extremely dangerous; would kinda require a fully sentient being.

Even for our more closely related prey mammals siblings; having that ability would just lead to problems. A deer just ‘random lt’ deciding to fall asleep? On what basis would it decide to do so?

So all of the brain and body has developed a tightly regulated system of basically comparing two signals: one is the body and brain saying ‘i need Rest’ and the other is the body and brain saying ‘we need to be awake because it is dangerous here, we are not yet done feeding for the day etc’

And the we need to rest signal will just continuously get stronger, until for animals that active in the day, it will in the evening make the brain go ‘better get into resting mode, and slow down the awake systems and go into restoration mode’.

This is caused by molecules like adenosine accumulating throughout every waking second; or melatonin which is being produced once it starts getting dark, or cortisol which is released in the very early morning to jump start you.

This way, baring disease, it leads to falling asleep when the body and brain needs it, and it is safest to do for the degree of need to be asleep.

Since all of these systems have evolved long before conscious though and sentience, they simply continued working like this once we became sentient. Because it’s good enough.