How powerful is a human brain in computing terms, and how exactly can it be quantified in order to be able ..?

Question

to make such a comparison?

Answer 1

I really do not think that the performance measures used for computers, e.g., millions of floating point operations per second, is an appropriate measure for the human brain.  Certainly computers can do computational mathematics quickly because they are designed for that purpose.  However, there is no computer that can control as many aspects of a human's physiology better than the brain.  

I was both a neurophysiologist and computer scientist.