This weekend, my friendly neighbourhood hospital pharmacist told me this story about a girl who suffered from horrible intestinal trouble from the tender age of 6. Her insides would clutch up so much that it was impossible for to live a normal life. She would miss days of school and days of work as she would suffer in her own guts' grasp.

My friendly neighbourhood hospital pharamacist described it as 'her stomach suffered migranes'. In fact, the girl's doctor prescribed her to lie in a dark room for light affects a person's serotonin levels. It is serotonin receptors, you may recall, that Prozac and other anti-depressants are used to act upon.

The girl's story has a happy ending. She took part in a double-blind research study of a new drug. Double-blind means that it is not only the patients who are unaware who has been given the drugs being tested and who has been given the placebo, but the doctors who are measuring the results and the effects of the drugs (and the placebos) have no idea either.

My friendly neighbourhood hospital pharamacist then told me that a drug has to be measured against its placebo. The drug that helped our little girl measured a 65% rate of success among the group who were administered the drug. But, because the placebo result was a startling 50% percent, it meant that the drug was only 15% better than nothing.

Clouding my brain as I heard all this story, was a dim recollection that not long ago, scientists had discovered a knot of brain nerves in the digestive tract. It's been called The Second Brain.

Brains. Guts. Headaches. Stomach Aches.

Correlation or Causation? Whatever the exact connection, the relationship between the cerebral and enteric brains is so close that it is easy to become confused about which is doing the talking.

The whole thing has confused both my brains.