SEEING a white light before you die could be caused by activity in your brain, a study suggests.
A surge of brain waves similar to consciousness occurs just before someone passes away, US researchers found.
GettyA surge of brain waves similar to consciousness occurs just before someone passes away, US researchers found[/caption]
This could be behind stories from people who have nearly died, saying they heard the voices of lost loved ones or saw bright lights when they were on the edge of death.
Researchers monitored brain activity in cardiac arrest patients after they were removed from life support.
They found gamma waves — the fastest waves produced in the brain — accelerated when they were taken off the machines, despite being unconscious.
Dr George Mashour, of the Michigan Center for Consciousness Science, said: “How vivid experience can emerge from a dysfunctional brain during the process of dying is a neuroscientific paradox.
“This important study helps shed light on the underlying neurophysiologic mechanisms.”
The study, published in Proceedings of the National Academy of Science, studied four patients who passed away due to cardiac arrest in the hospital while under EEG monitoring.
All four of the patients were comatose and unresponsive, and were determined to be beyond medical help.
After being taken off ventilators, two of the patients showed an increase in heart rate along with a surge of gamma wave activity.
The activity was in the part of the brain linked to dreaming, visual hallucinations in epilepsy, and altered states of consciousness in other brain studies.
This could cause things like flashes of light, although it was impossible to tell what the patients actually experienced because they died, the team noted.
Dr Nusha Mihaylova, of the University of Michigan said: “We are unable to make correlations of the observed neural signatures of consciousness with a corresponding experience in the same patients in this study.
“However, the observed findings are definitely exciting and provide a new framework for our understanding of covert consciousness in the dying humans.”