"They saw everything go away and then you got this activity"

Dr Stuart Hameroff, a professor of anaesthesiology and psychology at the University of Arizona, says he has recorded brain activity that suggests we have 'souls.'

The findings are from research carried out at George Washington University in 2009. This saw researchers place small sensors on the brains of seven clinically dead patients minutes before their life support was switched off.

Speaking to Project Unity, Dr Hameroff said: "They saw everything go away and then you got this activity when there was no blood pressure, no heart rate."

He explained that the researchers noticed a sudden flurry of brain activity in one patient, called gamma waves, believed to be involved in sleep, perception and movement.

This brain activity last up to 90 seconds and was picked up on an electroencephalogram (EEG).

These waves, produced by neurons firing on and off at the same time, were being produced even after the heart stopped beating.

"So that could be the near-death experience, or it could be the soul leaving the body, perhaps," Dr Hameroff added.

The anaesthesiologist suggested that consciousness could be so deep in our biology that our minds could operate on a quantum level - the very basis of matter and energy in reality.

So instead of consciousness being created by neurons firing each other, it could be microtubules, tiny cellular structures made of protein that control the shape of the cell and how it divides, the Metro reports.

This would explain why our consciousness would be the "last thing to go" when we die.

"The point is it shows that consciousness is actually, probably, a very low energy process," Hameroff said.

The researchers stated: "As the brain reaches a critical level of hypoxia, the [action potential, an electrical signal that shoots down a neuron is lost by large numbers of neurons, and this loss of electrical potential causes a cascade of electrical act."