What gives us the heavy feeling of “tiredness” in our brain/head when we’re tired?

Question

What gives us the heavy feeling of “tiredness” in our brain/head when we’re tired?

In: Biology

Answer 1

A chemical called Adenosine is formed in the brain when we are awake and as we exert energy. It then binds to the parts of our brain that control alertness and wakefulness. It is an inhibitory transmitter, meaning it slows down the activity in these areas. It also tells other parts of our brain to produce chemicals that make us feel sleepy. These effects of Adenosine lead to what we call “sleep pressure”, or the need to sleep.