The therapeutic benefits of laughter are widely known, however, and this is intriguing from the standpoint of basic science. Laughter is one of the most fundamental components of human behavior, transcending all age and cultural boundaries. It produces a hit of pure, direct pleasure. Yet scientists still do not understand what is happening in the brain to give such a positive feeling.Laughter breaks all the rules of survival. It uses up energy, makes predator-attracting noise and serves no obvious function in terms of gaining nourishment, accomplishing reproduction, or protecting from danger; yet it appears to be as natural as breathing. So fundamental is it, in fact, that people in all societies spend time—and often money—engineering themselves into situations where laughter is likely. It must be there for a reason.From psychological, zoological, medical and neuro-scientific standpoints, then, laughter should be at the top of the scientific research list. As a medicine it would be cheap and side-effect free; it ought to be promoted.But would scientific enquiry rob laughter of its quintessential merit, the elusive "feel-good factor"? There is no reason why this should be so. True, analyzing subjective conscious experience is one of the biggest and hardest questions facing those working on the brain, and laughter and pure fun are perhaps the hardest aspects of consciousness to come to grips with.