Laugh? I nearly got completely better

Once Upon a time there was a man, Norman Cousins, who was suddenly diagnosed as suffering from spinal disease and given a 0.2 per cent chance of survival. More than 20 years on, Cousins is still alive: he owes his life to a procedure that no one would have normally have prescribed for his condition. We now know that this same procedure helps minimise pain, counteract stress and improve immunity.

The procedure is unusual for several reasons. First, unlike many medical advances, doctors and scientists have suspected that it might be in some way therapeutic for quite some time. Thomas Sydenham, the "English Hippocrates" of the 17th century, with great insight and foresight predicted that, were it ever possible to set in train, then it would be more powerful than "20 asses laden with drugs". In the 19th century, Darwin thought that even in healthy people, it would enhance mental powers. A second surprising feature is that routine implement-ation of the procedure is only finally being promoted now. Certain clinics and hospital projects are being established where the procedure is practised and results so far are very promising. On the other hand, there is a basic problem in evaluating the clinical value of the procedure with any precision, because of the way clinical trials need to be conducted. In typical scenarios, the drug being tested is given to some patients but not others, with neither group knowing whether or not they had been given the drug or a "placebo". Since we are dealing with a procedure, it would be impossible for the patient to be ignorant of whether or not they had received it, particularly since it is essential that the patient be conscious.

Two great advantages of the procedure are that there are no side effects whatsoever, and that a clinician does not need to be present. Perhaps even more appealing, though, is that the procedure does not require high-tech equipment and would be cheap to instigate on a large scale nationwide, or even worldwide. In fact, the costs of setting it up in some form or other could actually be zero.

It sounds like the Holy Grail of all NHS mandarins. So it is surprising that not one of my basic medical books mentions it at all. One problem is that the reasons for the frequent triggering of the procedure, and indeed its basic mechanism of efficacy, are completely mysterious. When I did find a book on the subject, the author Robert Holden had counted as many as 80 different, and often contrasting, theories.

The procedure is to laugh. Apart from the clear therapeutic benefits that laughter seems to initiate, to which Cousins stands as testimony, I also find it intriguing from the standpoint of basic science. Laughter is one of the most fundamental components of human behaviour, transcending all age and cultural boundaries. Irrespective of the cause, why does laughter produce such a hit of pure, unadulterated, direct pleasure? What is happening in the brain that gives such a marvellous feeling?

It is also a strange activity in which to indulge since it breaks all the rules of efficient survival. Laughter uses up energy, makes predator- attracting noise and serves no obvious function in terms of gaining nourishment, accomplishing reproduction, or distancing ourselves from danger. And yet most of us will spend time and money engineering ourselves into situations where laughter is likely. From psychological, zoological, medical and neuroscientific standpoints, then, laughter should be at the top of the scientists' list for understanding.

Or is it that laughter is the last bastion of humanity, and so must be ring-fenced and protected from the probings of the scientist? Is there a fear that something so intimate is not tractable to scientific method, and conversely that scientific enquiry will rob laughter of its quintessential merit, the elusive feel-good factor? I do not see why it should be so. True, subjective conscious experience is one of the biggest and hardest questions for those working on the brain, and laughter and pure fun are perhaps the hardest aspects of consciousness to come to grips with. But what a shame to let nature have the last laugh.