After an after-death experience some people claim to have seen a bright white light at the end of a tunnel, others to feel the presence of loved ones, and others to have hovered over their bodies.

Now, scientists from the University of Michigan have announced that they have recorded activity in an area of ​​the brain responsible for consciousness.

Research by neuroscientist Jimo Borjigin and his team provides early evidence of an increase in consciousness-related activity in the dying brain.

“How the live experience it can result from a dysfunctional brain in its process of death it’s a neuroscientific paradox,” said Jimo Borjigin, who led the study. “We saw potential neuro-signatures of consciousness.”

The research

The researchers used data from the brains of four patients who were in a coma and not expected to survive. With the permission of their families, doctors disconnected the patients from life support machines. Shortly thereafter, the patients suffered cardiac arrest and died.

Scientists at the University of Michigan analyzed the brain activity data in the moments from the disconnection of mechanical support until the patients’ death.

After removal of mechanical ventilatory support, two of the patients presented with aincreased heart rate together with a flare up of the activity of C waveswhich is considered the fastest brain activity and is associated with consciousness.

The activity was detected in the so-called hot zone of neural correlates of consciousness, an area that has been associated with dreamsthe optics illusions during seizures and altered states of consciousness.

The other two patients did not show the same increase in heart rate or brain activity, according to the study published in the journal Proceedings of the National Academy of Sciences.

“It may activate the inner hidden consciousness, it may bring up past memories, it may be a survival mechanism of the brain, we don’t know,” Borjigin suggested.

In previous studies, Jimo Borjigin and colleagues have recorded similar signatures of gamma activation in the dying brains of both animals and humans after cardiac arrest.

However, due to the small sample size, the researchers stress, it is impossible to know what the four patients experienced because they did not survive.