[Hank]

Hank asked the Naked Scientists:

What physiological mechanism is at work in the old college trick of sticking a
sleeping person's hand in warm water to precipitate involuntary urination?

What do you think?

[Karsten]

Don't know if it works. I would wake up if anyone even took a breath in my presence when I am sleeping.

I assume it is based on the myth/phenomenon that one relaxes when exposed to warm water.

Karsten

[Chemistry4me]

A question similar to this has been asked before: http://www.thenakedscientists.com/forum/index.php?topic=18867.0