In Tibetan Buddhism, there’s a mystical concept known as “thukdam” or “tukdam,” in which an experienced meditator can slip into a state of mind said to be accessible at the time of death. The brain is believed to be “dead,” unable to register sensory impressions, yet some flickering of consciousness remains in the body. As per the tradition, mastery of tukdam can help a meditator prolong the process of death. After entering this state, a person can be declared dead, but the body will remain seated upright, their skin remaining supple and bright. The Dalai Lama, the spiritual leader of the Tibetan people, has said: “Individuals in tukdam... can remain in this state for a week or even a month according to their own wish.”
This might not sound like the typical domain of science, but the phenomenon has attracted the attention of numerous neuroscientists, doctors, psychologists, anthropologists, and Western philosophers in recent years.
Earlier this year, a multidisciplinary team from the Center for Healthy Minds at the University of Wisconsin–Madison published the first peer-reviewed paper on the phenomenon of tukdam. Reported their findings in the journal Frontiers in Psychology, researchers attempted to study brain activity of 14 long-term meditation practitioners (as healthy baselines) and compared it to 13 recently deceased practitioners who were said to have entered a state of tukdam.
And what did they see? Well, not much. The researchers did not detect any measurable brain activity in the 13 deceased people. However, they note that the earliest recording could only be achieved 26 hours after their death. As for reports that the bodies remain "fresh" after what appears to be their death, this remains unconfirmed.
Nevertheless, the researchers are not despondent by their findings. Western medicine has typically seen death as a binary state, like an “on” and “off” mode. However, some recent research has helped to challenge this view. Earlier this year, another study in the New England Journal of Medicine saw scientists closely monitoring the vital signs of over 600 seriously ill patients while they were being taken off life support. The key finding was that the heart can often stop and restart several times during the dying process before it totally stops for good. While this is still a long way from more spiritual ideas of life's final moments, it does suggest that death isn’t an acute “lights off” instance, but perhaps a process.
“In Western medicine, death is conceptualized in a binary state – either you’re alive in one moment or dead in another,” Richard Davidson, author of the recent study and director of the Center for Healthy Minds and the William James and Vilas Professor of Psychology and Psychiatry, said in a statement. “Yet biological processes don’t work in a simple on-off way. They are more graded. We hope this research catalyzes a conversation around the process of dying and raises questions about dying as a process and not a binary switch.”