Study uncovers what happens in the brain in the interval between life and death
Many are the stories told by those who have gone through processes of loss of consciousness such as a coma; a tunnel with a light at the end, a review of the most outstanding images of their life, etc. Well, researchers from the University of Michigan (UMich) in the United States have carried out a study based on data from four patients who died of cardiac arrest while under electroencephalogram (EGG) monitoring. to estimate the processing of our brain at this stage.
As this study published in the journal states. Proceedings of National Academy of Sciences: “While overt loss of consciousness is invariably associated with cardiac arrest, it is unclear whether patients may possess an ‘covert’ consciousness during the dying process.”
For the research, the scientists examined EGG signals by applying computational tools used in a previous study applied to animals. These signals were used because this -EGG- is the unique measure of brain activity which constitutes how awake a patient is in processes such as coma or general anesthesia.
“Larger multicenter studies, including ICU patients with monitored EEGs who survive cardiac arrest, could provide much needed data to determine whether or not these bursts in gamma activity are evidence of an occult consciousness even near death,” says researcher Jimo Borjigin.
Brain activity in the ‘hot zone’
Of the four patients analyzed, two of them showed a rapid and marked surge of gamma power, a surge of gamma wave cross-frequencies with slower oscillations, and increased functional interhemispheric connectivity directed in gamma bands.
This gamma activity was stimulated by global hypoxia (when no oxygen reaches the brain) and increased further as cardiac conditions deteriorated in patients on the verge of death. The brain activity was observed, specifically, in the ‘hot zone’ of the neural correlates of consciousness in the brain. This zone is located in the parieto-occipital region of the cerebral cortex, and its finding is relevant because it has been related to the neural correlate of dreams.. That is, when this area is stimulated during wakefulness, the sensation of living in a parallel world is induced, which is popularly known as dreaming.
Thus, the results of this study demonstrate that during the death process of these humans, a surge of gamma energy and brain connectivity could be seen which could be assimilated to some last processes of activity in the brain.