Near-death experiences (NDEs) have captivated our imagination and become deeply ingrained in our cultural landscape. These remarkable accounts often involve encounters with white light, visits from departed loved ones, and hearing voices, among other vivid attributes.
The striking similarity among these reports raises profound questions about the underlying reality and suggests that individuals who have survived death may offer glimpses of a consciousness that persists beyond the cessation of heart activity.
New Study Provides Early Evidence of Consciousness-Related Activity in the Dying Brain
In a recent publication in the Proceedings of the National Academy of Science, a groundbreaking study sheds light on the enigmatic nature of near-death experiences. The research presents compelling preliminary evidence of a surge of brain activity that correlates with consciousness in individuals on the brink of death.
A team led by Jimo Borjigin, Ph.D., an associate professor in the Department of Molecular & Integrative Physiology and the Department of Neurology, conducted a study that builds on animal studies carried out almost a decade ago in partnership with George Mashour, M.D., Ph.D., the founding director of the Michigan Center for Consciousness Science.
The study found comparable patterns of gamma activation in the dying brains of both animals and humans after experiencing oxygen deprivation due to cardiac arrest.
“How vivid experience can emerge from a dysfunctional brain during the process of dying is a neuroscientific paradox. Dr. Borjigin has led an important study that helps shed light on the underlying neurophysiologic mechanisms,” remarks Mashour.
The research team identified four patients who had experienced cardiac arrest in the hospital while being monitored with an electroencephalogram (EEG). All four patients were comatose and unresponsive, and after being determined to be beyond medical help, they were removed from life support with their families’ consent.
When ventilator support was discontinued, two of the patients demonstrated an increase in heart rate and a surge of gamma wave activity. Gamma wave activity is the fastest brain activity and has been associated with consciousness.
The observed activity was located in the “hot zone” of neural correlates of consciousness, which is situated at the junction between the temporal, parietal, and occipital lobes at the back of the brain. This area has been linked with dreaming, visual hallucinations in epilepsy, and altered states of consciousness in other brain studies.
Two of the patients in the study had a history of seizures, although they did not experience any seizures during the hour leading up to their deaths. Nusha Mihaylova, M.D., Ph.D., a clinical associate professor in the Department of Neurology who has collaborated with Dr. Borjigin since 2015 and collected EEG data from deceased patients in the ICU, provided this information. In contrast, the other two patients did not exhibit an increase in heart rate upon removal from life support, nor did they show heightened brain activity.
It is important to note that due to the small sample size, the authors caution against drawing broad conclusions about the implications of these findings. Furthermore, the study could not ascertain what the patients experienced during this time since they did not survive.
“We are unable to make correlations of the observed neural signatures of consciousness with a corresponding experience in the same patients in this study,” she points out.
“However, the observed findings,” according to her, “are definitely exciting and provide a new framework for our understanding of covert consciousness in the dying humans.”
Conducting larger, multi-center studies that monitor the EEG activity of ICU patients who survive cardiac arrest may offer valuable data to establish whether the surges in gamma activity observed in dying patients signify concealed consciousness close to death.
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