The human brain shows larger-than-life activity at the time of death

The brains of dying people can trigger sudden life in their final moments.

According to a study published Monday, two apparently brain-dead people taken off life support showed sudden spikes in neural activity.

Findings published in Proceedings of the National Academy of Sciences provide scientific support for accounts of “near-death experiences” – powerful and often mystical experiences that occur when a patient is near death.

But they also shed new light on the surprisingly murky question of how we die, said Jimo Borjigin of the University of Michigan.

In a small study of four patients taken off life support, Borjigin’s team discovered something surprising: the brains of two of the four sprang to life in the moments before death.

In particular, patients exhibited a sudden increase in the specific type of brain waves that usually indicate conscious thought.

The production of these brain waves – called gamma waves – increased up to three hundred times their previous levels in a patient in the moments before death.

The gamma wave patterns of this dying patient reached higher levels than those found in normal conscious brains.

The process our body and brain go through when we die remains poorly understood. In the conventional narrative, death is simply the sudden termination of life processes, especially brain and heart activity.

For example, scientists don’t really understand what happens on the inside when a seemingly healthy person suffers a sudden trauma – like a car accident, a fall, or a heart attack – and quickly dies.

“If you don’t know exactly how they die, how do you save them?” Borzhigin asked

In practice, a person is legally dead when declared dead by a medical professional.

This professional does not make this call on the basis of a thorough inventory of the patient’s subjective mental state, but on the basis of the persistent absence of heartbeats or brain waves.

After a long period of inactivity, family members often choose to disconnect a patient from breathing apparatus, in which case their body slowly dies from lack of oxygen.

But recent findings suggest that something more complex and harder to detect is going on. Borjigin points out that there remains the possibility that a “secret consciousness” – a conscious experience that we are not currently able to detect – continues below the surface and comes back to urgent life as death approaches.

This may be an adaptive response similar to the spurt of cognitive activity that wakes a sleeping person (or, perhaps, a seal) with sleep apnea — in which the body stops breathing during sleep — in time to recover, Borjigin said.

“The brain has an extremely sensitive mechanism for sensing oxygen levels in your body,” she said. “Even tiny drops in oxygen levels – the brain knows this and is constantly regulating the oxygen supply.”

This goes against the idea of ​​the brain as a passive passenger – which Borjigin says makes sense.

“To think that when you have a cardiac arrest – where the heart stops or doesn’t pump blood – and the brain doesn’t do anything? It’s beyond my skills. The brain should go crazy – that’s exactly what’s happening,” she said.

His next hypothesis is that “the brain drops everything discretionary to focus on that essential function of survival, or self-resuscitation.”

This exploration of the inner territory of death is a far cry from Borjigin’s original area of ​​specialization: circadian rhythms and the science of sleep.

In 2008 she was study the impacts of stroke on the brain’s production of hormones that promote sleep, when she accidentally discovered something shocking.

In the moments before death, the rats’ brains connected to their machines displayed a sudden surge in serotonin, a brain chemical deeply linked to thought and sensing processes.

“Serotonin, as you probably know, is the essential neurotransmitter that’s important for the functioning of the brain — which, when it malfunctions, can lead to psychiatric disorders,” Borjigin told The Hill.

“So the first thing I thought – ‘Wow. I wonder if rats have hallucinations?’ »

His second thought was that this serotonin surge was probably a well-understood phenomenon. She was wrong – both about that and about understanding the general mechanics of death. “I started looking in the literature and was surprised to find that we literally knew next to nothing.”

In the conventional understanding of death, the brain is a semi-passive passenger carried by the heart — and it dies when the heart dies, Borjigin said.

There isn’t much room in this model, however, for what Borjigin had discovered: a sudden increase in activity in dying brains. She built on those findings in a 2013 PNAS study that found that the brain of the dying rats produced a surge of gamma waves – the indicative pattern of consciousness – as they suffered heart attacks.

“These data demonstrate that the mammalian brain can, albeit paradoxically, generate neural correlates of increased conscious processing as death approaches,” his team wrote in the 2013 paper.

This sentence contains an important caveat, and it is the one that hangs over all of this research. Dying rats may show “correlates” or traces of the activity which, in conscious mammals, is linked to consistent brain activity – but it is so far impossible to know, subjectively, what rats are experiencing or dying humans.

Nevertheless, the 2013 paper, with its findings on increased brain activity in dying rats, made the New York Times. His findings, writes the Times, could “explain the vivid and realistic visions experienced by some human victims of cardiac arrest” – visions reported by about 20% of heart attack patients.

These findings, Borjigin wrote at the time, may “explain why some people, during this state, can actually recall conversations that took place in the operating room.”

These findings helped push Borjigin to the frontiers of consciousness research. His sleep research focused on the pineal gland, a roughly almond-shaped organ below the forehead that releases the hormones that regulate sleep — and which many philosophical traditions have assumed to be the seat of consciousness.

In 2013, Borjigin worked with Rick Strassman of the University of Mexico School of Medicine on a study that found the chemical dimethyltryptamine (DMT) — the active ingredient in the powerful Amazonian psychedelic ayahuasca — in the pineal glands of rats.

Strassman is a leading scientist who helped revive research into the medical applications of psychedelics in the 1990s, sparking a renaissance in a field that medicine had largely turned away from since the 1970s.

Many of Strassman’s assumptions — including that the brain releases a surge of DMT upon death, a phenomenon he suggests may be linked to end-of-life religious experiences — don’t sit well with mainstream medical understanding.

But in 2019, Borjigin and Strassman discovered that dying rat brains released a surge of DMT Also.

That’s a strong indicator that human brains do something similar, Borjigin told an interviewer at the time – because the cognitive phenomena found in rats generally manifest themselves in humans as well, but not the other way around.

It’s hard to investigate much beyond that, however. Testing for a dying surge of DMT is highly invasive and – in the absence of end-of-life volunteers willing to have their skulls cut open at the time of death in the name of science – very difficult to substantiate.

And although the National Institutes of Health has devoted money and attention in recent years to medical applications of psychedelics – especially around cure depression or stop dangerous drugs like alcohol Or cigarettes – these studies largely focus on helping those who are unambiguously alive.

Additionally, “while psychedelic research has recently seen a renaissance, it’s primarily the use of psychedelics as medicine or drugs,” Borjigian added – rather than the study of how similar chemicals are produced. and used by the mammalian brain.

Since she began her studies of the cognitive life of the dying a decade ago, Borjigin has not received a single grant from the NIH, she told The Hill.

“We definitely need to expand our studies, and we need NIH funders for these kinds of studies — to just study a lot more patients, maybe across a whole national network.”

This could lead to a reassessment of how the heart and brain work together to avoid the point of death — and therefore, potentially, to a better understanding of their role in keeping us alive, Borjigin said.