Leonardo da Vinci and Lewis Carroll could both “mirror write,” writing from right to left, reversing each letter so that the script looks normal when held up to a mirror. One theory is that mirror writing is a sex linked dominant hereditary trait, particularly among left handed people, with mirror writers benefiting from not one but two language centres, one on each side of the brain, connected via the corpus callosum (Medical Hypotheses 2004;62: 733-9).

Despite repeated beatings about the head, 82 amateur boxers participating in multiple bouts during a seven day tournament showed no evidence of cognitive dysfunction immediately afterwards. Their serial performance in tests of simple reaction times, choice reaction times, and working memory tests after three bouts was equal to that of boxers who had taken part in one and two bouts, and that of non-boxing control participants. Boxers whose bouts had been stopped by the referee proved the exception (Neurology 2004;62: 1497-502).

Smoking can cause chronic obstructive pulmonary disease, but only 15-20% of smokers get it. A study in Chest (2004;125: 1706-13) shows that bronchial cells from smokers who have obstructive disease produce a greater inflammatory response to stimulation with an irritant (tumour necrosis factor alpha) …