So what would it be like to be a disembodied brain? The truth is, nobody knows. But it is probable it would be worse than being simply tedious — it would likely be deeply disturbing. They say his brain will be overwhelmed by the unfamiliar chemical and electrical signals sent to it by his new body, and it could send him mad.
A disembodied brain would be likely to react similarly — but because it would be unable to signal its distress, or do anything to bring its suffering to an end, it would be even worse. It is far from clear whether your disembodied brain would even be you.
The question of when people die is the subject of ongoing philosophical debate as well as my own research. In a number of published papers, I have investigated this question and how it relates to what makes us who we are, how we persist over time, and what changes we can survive.
Some working in this area think we are purely psychological beings, and so could survive as disembodied brains so long as our memories and personalities were preserved. So, because you die when your body does, your brain cannot be you. And so even if it has the same personality and memories as you, it can only be, at best, a psychological duplicate of you. But we should also be deeply concerned about the possibility of reanimating conscious human brains from an ethical standpoint.
According to the dominant view in ethics, living human beings possess full moral status — that is, they are deserving of the highest possible degree of moral respect. They have such a status by virtue of possessing high-level psychological properties that are grounded in the capacities of the conscious human brain. And so, according to this view, irrespective of whether your disembodied conscious brain would be you, it would still be an entity with full moral status.
Enter your keywords. Sign-Up Here. Chemical Witchcraft in Salem 28 Oct Happy Ether Day! Is it true that the Beatles wrote a song about LSD? Facebook Twitter YouTube Instagram. Accessibility Log in. In these immunofluorescence images, neurons appear green, astrocytes are red and cell nuclei are blue. Intuitively, we tend to think of resurrection as a spectacular, showy event: a phoenix rising from the ashes. But on a cellular level, resurrection is less a triumphant transformation than the crescendo of a finely tuned orchestra.
Their internal generators slow , their organelles may fragment, and their DNA breaks down. To mount a resurrection bid, cells must reverse these processes and attempt to repair the damage through a complex, tightly choreographed operation. They can often jump-start this intricate recovery on their own — a discovery that emerged several years ago as scientists questioned old assumptions about the finality of cell death.
The Tangs had long heard that once cells enter apoptosis, a classic death sequence many cells go through, they cannot be brought back to life because of caspases — the so-called executioner enzymes that chop cellular proteins into fragments. Caspases were considered the final death knell for almost any cell: Once they appeared, there was supposedly no way apoptosis could be reversed.
To find out, in the Tangs designed a simple experiment. They immersed human tumor cells in ethanol to kick-start apoptosis. But instead of tossing out the presumably dead cells afterward, they washed the cells and put them in a fresh culture medium. The results were shocking. By the next morning, some of the cells had regained their normal, healthy appearance. In place of the shrunken, shriveled cells they had left, they found flush cells with intact membranes.
Key organelles such as mitochondria were functioning normally again. All signs pointed to a dramatic reversal overnight — a cellular greatest comeback. Before treatment, the cell looks healthy. After 2. Washing and incubating the cell in fresh medium for an hour then returns it to a more normal appearance.
Click on the second and third images to watch time-lapse video of those changes. When the two scientists identified the enzymes active during this process, they confirmed that cells could recover even after caspases had begun to chop up their innards. The cell biologist Denise Montell — who worked with the Tangs at Johns Hopkins and was a co-author on the paper — had also begun questioning the existence of a cellular point of no return. To investigate, Montell, now of the University of California, Santa Barbara, submerged some human cancer cells in alcohol to initiate cell death.
The alcohol had the expected effect within a few hours: The cells began to shrink, their membranes bulging like water balloons with weak spots. Initially, she thought the cells had completely recovered after just two hours, but after 12 hours she realized that the cells looked much different than they had 10 hours before. In the first phase of anastasis, cells whose growth has been stopped during apoptosis begin to grow again and resume a normal cell cycle.
In the later stage, after about half a day, the cells begin to elongate and move around more than before as they divide and reproduce — a response that, in live animals, could help damaged tissues fill in and regrow. Montell also noticed that genes promoting growth and recovery were active during apoptosis to some extent, suggesting that the seeds of potential anastasis are sown even as apoptosis begins.
That allows them to see which cells progress partway through apoptosis, then reverse gear and return to normal function. The researchers have used various techniques to demonstrate that anastasis occurs in organisms ranging from fruit flies to rodents. That suggests anastasis may persist because of the evolutionary advantage it offers. If some cells die in the face of nutrient shortages, for instance, more nutrients will be available for the surviving cells to consume — provided they can reverse the death sequence.
When Hogan and Holly Tang gave fruit flies a protein-rich feast after days of deprivation, fly egg cells that had started apoptosis reversed course and repaired themselves. Anastasis, then, is a counterweight to the cellular pruning bodies perform under stress, an energetic yang to the yin of apoptosis.
While anastasis is a relatively recent discovery, a subtler form of resurrection has intrigued biologists for decades: the process cells use to dredge themselves out of deep dormancy. In a wide range of species, certain cells can slow down their activity dramatically, like lights that dim without quite going dark.
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