About one patient in ten of those resuscitated in such units report afterwards that they had some conscious experience while apparently dead.
Dr Peter Fenwick of the Institute of Psychiatry has arranged for messages to be placed near the ceiling of a coronary care unit which could only be seen by someone or their 'spirit' who was actually hovering up there.
The experience of 'nipping up to the ceiling', as he decribes it, is commonly reported by patients believed to be dead in 'after death' experiences.
The objective reality of this experience is being tested in a number of ways. One is the incorporation of an optical illusion into the ghost-detector, to see if subsequent reports mention the illusion or what is really there.
If the experiment were to show that people can obtain information quite independently of sense perception, we would have to reformulate a great many of our philosophical ideas, Dr Fenwick said yesterday. 'At least we would have to decide whether our ideas of the relationship between body and mind were correct.'
The experiment has been running for two months, and will run for at least another four. Two out- of-body experiences have been reported. 'I don't know whether they saw it or not,' Dr Fenwick said. 'They may have gone down instead.'
Going down a long tunnel or meeting a beam of light are the other two common features of near-death experiences, though the name is a misleading one, since at the time they appear as after-death experiences.
There is some correlation, Dr Fenwick said, with educational level; the more educated you are, the more likely you are to report back interesting things from the far side of the grave. He is seeking funding to prolong his experiment beyond six months. 'But funding bodies are more interested in molecular biology,' he said.