Scientists to uncover the truth of out-of-body experiences
Last updated at 2:33 PM on 19th September 2008
Some see a tunnel or a bright light. Others float above their hospital bed, looking down at doctors and nurses from the ceiling of an operating theatre.
Now - in the biggest study of its kind - scientists are to examine the near-death experiences of 1,500 hospital patients to see if out-of-body experiences are real or just a trick of the mind.
During the three-year investigation, doctors will place pictures on shelves high up in hospital rooms so that they can be seen only from above.
A team of doctors will study the 'out of body' experiences of 1,500 heart attack patients
If any patients recall the images, it would be the first hard proof that out-of-body experiences are real.
Dr Sam Parnia, who is leading the study at University of Southampton, said: 'If you can demonstrate that consciousness continues after the brain switches off, it allows for the possibility that the consciousness is a separate entity.
'It is unlikely that we will find many cases where this happens, but we have to be open-minded.
'And if no one sees the pictures, it shows these experiences are illusions or false memories. This is a mystery that we can now subject to scientific study.'
Around 10 to 20 per cent of people whose heart stops after a cardiac arrest report some near-death experiences.
These include memories, thoughts and sometimes detailed recall of the events during their brush with death.
The study will look at survivors from heart attacks at 25 UK and U.S. hospitals who experienced periods with no heartbeat or measurable brain activity.
During the study, doctors will use technology to study the brain and consciousness during cardiac arrest.
At the same time, they will test the validity of out-of-body experiences and patients' claims of being able to 'see' and 'hear' things while unconscious.
The researchers have set up special shelving in resuscitation areas. The shelves hold pictures – but they're visible only from the ceiling.
Hospitals involved include Addenbrooke's in Cambridge, University Hospital in Birmingham and the Morriston in Swansea, as well as nine hospitals in the U.S.
'Contrary to popular perception, death is not a specific moment,' said Dr Parnia. 'It is a process that begins when the heart stops beating, the lungs stop working and the brain ceases functioning.
'There then follows a period of time, which may last from a few seconds to an hour or more, in which emergency medical efforts may succeed in restarting the heart.
'What people experience during this period provides a unique window of understanding into what we are all likely to experience during the dying process.'
Many people who have gone through a near-death experience believe they have glimpsed the after-life.
Some report hearing voices telling them to return to the living world, others feel a tremendous sense of peace and well-being.
But scientists argue that the experiences have a biological basis.
Researchers have shown that the same parts of the brain are activated in near-death experiences as dreams and that people who report them are able to slip into a dream state more easily than others.
HOW TO TELL IF YOU'RE DEAD
If someone stops breathing, it can take several minutes before their heart slows down and comes to a stop.
But if their heart stops first - because of a cardiac arrest - breathing stops within seconds. This is the point of ‘clinical death’.
Consciousness is normally lost within a few seconds of clinical death, but the brain can survive unharmed for around four minutes.
It is during this period of unconsciousness that so-called out-of-body experiences happen, scientists say.
After four minutes, oxygen starvation starts to cause brain damage. Once the brain stem – the part of the brain that handles automatic tasks such as heartbeat and