Why the room spins when laying down drunk
It's because the alcohol changes the density of some of the bits of your balance system.
Your balance sensors are in each inner ear on each side of your head. There is a small blob of jelly, attached to the 8th Cranial Nerve.
The blob of jelly normally has exactly the same density as the liquid (endolymph) which surrounds it. So the little blob of jelly in the liquid will neither sink nor float - but it will move if there's any acceleration going on. When it moves it stimulates the 8th Cranial Nerve, which then sends signals to your balance centres in your brain.
When alcohol gets into the blood stream, it slowly diffuses into the endolymph, and makes it more dense. So the little blobs of jelly begins to float, and this stimulates the 8th Cranial Nerve, giving you the impression that your bed is spinning.
As the night wears on, the alcohol gradually diffuses into the blob of jelly as well, making it as dense as the liquid it floats in - so the spinning sensation lessens. After a few more hours, the alcohol begins to leave the endolymph, so now the blob of jelly is slightly denser, and you get the impression of spinning in the opposite direction.
So you could go to sleep with the room spinning one way, and wake up with it spinning the other way.
Dr Karl S. Kruszelnicki
This was a regular occurrence for me during my drinking years. The room always seemed to spin anticlockwise.
Though it was not still spinning when I woke up.
Your balance sensors are in each inner ear on each side of your head. There is a small blob of jelly, attached to the 8th Cranial Nerve.
The blob of jelly normally has exactly the same density as the liquid (endolymph) which surrounds it. So the little blob of jelly in the liquid will neither sink nor float - but it will move if there's any acceleration going on. When it moves it stimulates the 8th Cranial Nerve, which then sends signals to your balance centres in your brain.
When alcohol gets into the blood stream, it slowly diffuses into the endolymph, and makes it more dense. So the little blobs of jelly begins to float, and this stimulates the 8th Cranial Nerve, giving you the impression that your bed is spinning.
As the night wears on, the alcohol gradually diffuses into the blob of jelly as well, making it as dense as the liquid it floats in - so the spinning sensation lessens. After a few more hours, the alcohol begins to leave the endolymph, so now the blob of jelly is slightly denser, and you get the impression of spinning in the opposite direction.
So you could go to sleep with the room spinning one way, and wake up with it spinning the other way.
Dr Karl S. Kruszelnicki
This was a regular occurrence for me during my drinking years. The room always seemed to spin anticlockwise.
Though it was not still spinning when I woke up.