Head's up: Brains found to survive decapitation

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A burst of brain activity dubbed the "wave of death" may not signal the end after all, a new study finds.

This burst, seen in the brains of rats about one minute after decapitation, is a result of brain cells suddenly losing access to oxygen and energy, but it is not necessarily irreversible, according to the research published online July 13 in the open-access journal PLoS ONE. Earlier this year, another group of researchers had suggested that the "wave of death" might signal brain death.

"In fact," researchers wrote in the new study, "this wave does not imply death, neither of neurons nor of individuals."

Time of death

The study highlights the difficulty of pinpointing the moment of death. Doctors now think of death as a process: The breath and heart must cease, as must brain activity.

Normally these three events take place in relatively quick succession, but that doesn't mean that all of the cells of the body are dead. For example, a 2002 study published in the Journal of Cellular and Molecular Medicine found that brain cells taken from a person several hours after death could survive for weeks in the lab.

Of course, brain cells surviving in a dish aren't the same thing as a live, conscious brain. In a study published in January in PLoS ONE, Dutch neuroscientist Anton Coenen of Radboud University Nijmegen and his colleagues were concerned about the ethics of killing lab rats via decapitation. The question, the researchers wrote, was whether awake rats suffer from a swift beheading or they quickly lose consciousness and avoid much pain.

To find out, the researchers decapitated both awake and anesthetized rats while measuring the electrical activity in the animals' brains with an EEG, or electroencephalograph.

In both awake and anesthetized rats, the EEG went dead about 17 seconds after decapitation -- though the researchers noted that it was at a low enough level to suggest a lack of consciousness within 3.7 seconds. Then they noticed something strange: About a minute after decapitation, a slow, large electrical wave roiled through the rats' brains.

Point of no return

Coenen's team speculated that this wave was the brain finally giving up the ghost. Neurons communicate with electrical signals, which they generate thanks to an imbalance of positive and negative charges along their cell walls. This imbalance is called a "membrane potential." Coenen and his colleagues speculated that the "wave of death" they saw on the EEG was the final loss of the membrane potential and a sign of irreversible brain death.

In the new paper, neurologist Michel van Putten of the University of Twente in the Netherlands and his colleagues used a computer model to simulate the chemical changes that happen in the brain during death of rats. They, too, found the wave of death. But van Putten and his colleagues don't agree that the wave represents a point of no return for the brain.

Even after the wave of death, the researchers wrote, the brain cells could still theoretically rally if resupplied with oxygen and glucose, the sugar that drives the brain. As evidence, the researchers point to the brain cells taken from deceased humans living on in the lab, as well as to a 1981 study published in the journal Stroke in which scientists saw electrical activity return to brain cells after 15 minutes of oxygen deprivation.

Coenen was reportedly pleased that the results of the modeling experiment matched his real-world observations in beheaded rats. However, Coenen told ScienceNews magazine, he still believes that the damage wreaked by the wave of death is irreversible. He plans to investigate further.

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[pdchapin]

I'm a big supporter of using animals in meaningful medical research but the line "In both awake and anesthetized rats, the EEG went dead about 17 seconds after decapitation" is disturbing. I can't see the point of this research and decapitating awake animals to study how long it takes them to die is a bit sick. It's research like this that give PETA ammunition to attack legitimate research.

[ibsteve2u]

"About a minute after decapitation, a slow, large electrical wave roiled through the rats' brains."

Huh. Maybe the St. Peter of rats is...reviewing.

[erasmus111]

"He plans to investigate further."


He should investigate further by experimenting on humans. Perhaps he should be used as the guinea pig.

I fail to see why animals should be used, when it's something to benefit us humans. The only sure way to know if something is harmless, or beneficial to us is to test on us. It would save millions of animals lives and it would also give quicker results. As it is, we test on animals for years and it still doesn't really answer whether it's safe for us until it's tried on us. Just think of the time and money saved.

If us humans need to have all our "things" and we feel the need to live longer, then we need to figure it out by using our "selves" as test subjects.

[Bobtheplumber]

I imagine that you use medicine, when you get sick you get antibiotics? When you go to the hospital you get medicine or get treated with the newest advances. You can't have it both ways. Okay first of all no money would be saved at all. Research would completely die thus shutting down a huge industry in America. So really only money would be lost if we stopped experimenting on animals. The only time they test on people is when they work most of the kinks out of the drug or treatment. You can't seriously be proposing that we take untested ideas and just say here Ted drink this maybe it'll improve your cancer. I'm sorry but morally and ethically even you wouldn't actually support that. The facts are simple, lab mice or rats are raised to be experiments. Their DNA is around 80-90% match to ours. So actually it is safe to experiment on them because it is like experimenting on us.

[Mike_in_USA]

would you please contact this researcher and volunteer for one of the experiments?

[pingnak]

The real news here is that some psychos are vivisecting animals for kicks, and CBS News thinks it's 'science'.

They ALREADY know how to kill rats humanely. A rat guillotine would be totally inhumane, even if it were reliable and 'instant', when triggered. You have to trap the rat in a device that won't let its head move. It's going to struggle, panic, etc. Terrifying. Then off comes its head. Messy, too.

So the only possible conclusion is they had time on their hands, and wanted to see what would happen when you whacked rats' heads off. Probably after some historical debate about guillotines.

[lucifersshadow]

"In both awake and anesthetized rats, the EEG went dead about 17 seconds after decapitation -- though the researchers noted that it was at a low enough level to suggest a lack of consciousness within 3.7 seconds."
3.7 seconds would be a long time . . . if it were you. I suppose the doctors during the French Revolution who stated that the guillotine was a humane way to execute "criminals" were quite wrong. Someone ought to publish this in Saudi Arabia.

[rf35]

So beheading isn't a quick and humane way to die?

[retiredgustav]

I remember reading stories of how the lips would be moving as if the recently beheaded were speaking. I wonder what their last words were?

[DrKnowe]

@retiredgustav:
"oh shi......."