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"Correction | The article originally stated that the brain had been recovered. It has been updated to clarify that the rabbit brain has so far only been preserv

by ipsum2 11y ago

"Correction | The article originally stated that the brain had been recovered. It has been updated to clarify that the rabbit brain has so far only been preserved, not recovered." This is a far ways away from "returns successfully". The research just states that they can preserve the physical structure of neurons.

daenz 11y ago
What's great about merely preserving is that as long as we can preserve "indefinitely", the probability of future tech being able to recover the brain approaches 1.
- stcredzero 11y ago
  Assuming civilization doesn't collapse and the human race doesn't go extinct before becoming "The Progenitors."
- ryanhuff 11y ago
  Perhaps, but that's not helpful if the probability of the infrastructure to support the preservation (family who cares, businesses, or even civilization) surviving to reach that point approaches 0.
  - daenz 11y ago
    Then it's not indefinite preservation :)
- AnimalMuppet 11y ago
  But, see, until someone successfully recovers, we don't know if we successfully preserved enough for a successful recovery.
- wlesieutre 11y ago
  Alternately, all the people who would have been working on solving those problems say "I'll get my brain preserved so I can wake up and live in the awesome future after someone else solves how to thaw me!"
- Houshalter 11y ago
  That's the awesome thing about cryonics. It's like forward time travel, an ambulance ride to the future. We have found organisms almost perfectly preserved for thousands of years in far worse conditions, including seeds that were able to grow and living viruses and bacteria. As long as the synapses that make you you are preserved, then a sufficient level of technology could revive you. Whenever cryonics comes up on HN there is usually a lot of negative comments. It seems "weird" and that really repels people. That was my first reaction to it. As a kid I saw a photo of a cryonics facility in some magazine. A bunch of metal tubes with frozen dead bodies inside. I thought it was really creepy and disturbing. Pictures of thawing rabbit brains aren't exactly enticing.
- Retric 11y ago
  Analog systems decay even at low temperatures.
nxzero 11y ago
Thanks; kills me how corrections are placed at the bottom of a story by some pubs.
zck 11y ago
From criticisms I've read of freezing a brain by infusing it with aldehyde, it destroys things necessary for brain function, such that it will be impossible to bring a brain frozen this way back in the future. P.Z. Myers^1 has said (http://freethoughtblogs.com/pharyngula/2016/01/29/how-can-you-protect-a-brain-by-destroying-it/ http://freethoughtblogs.com/pharyngula/2016/01/29/how-can-yo...): >I was fixing zebrafish brains with a cocktail of acrolein, glutaraldehyde, and paraformaldehyde in the 1980s, trying to capture detailed images of synapses in the spinal cord. It worked pretty well, too. They know what they are getting out of this: an aldehyde-preserved brain. >What I didn’t do with my experiments in aldehyde-preserved brains was claim that I was preserving all the information necessary for nervous system function. I was quite aware that I was chemically nuking all the proteins in the tissue; I was washing out most of the chemistry; I was destroying most of the physiological information to preserve a structural skeleton of what was there, so I could see the physical arrangement of the pieces. Nothing more. And later: >The pattern of synaptic connections is an essential part of the story, but it is not sufficient. A simple counterexample: consider the effect of MAO inhibitors and various antidepressants. They modulate the activity of the brain by affecting the intercellular concentration of neurotransmitters. ... > These things are all destroyed by fixation. The information is no longer there. > If this organization is so confident that they have preserved all the necessary information, I’d like to know why they’re playing around with just the first step of the problem, doing so in impractically complex organisms, and not working on the necessary step of recovering that information. That’s the real test. > Take a simpler organism, like a fruit fly or a nematode. Kill it, fix it, freeze it, vitrify it. That should be trivial at their tiny scale. Then rebuild a fly brain from the extracted information and show me that it still knows how to walk, fly, eat, court, and mate. It's reasonably convincing [1] I know he's considered somewhat controversial, but he's a biologist here speaking a sub-topic in biology he's worked in. Even if you don't like him, this can't be dismissed out of hand.
- Houshalter 11y ago
  The synapses are the important part. The other information can be inferred or reconstructed. But your memories and behaviors are stored in the connections and weights of synapses. His test is extremely unrealistic. No one is claiming to have the technology now to be able to revive cryopreserved brains. All we can do is try to preserve as much information as possible so future technology will have more to work with.
dang 11y ago
Ok, we changed the title to incorporate that.

by ipsum2 11y ago

daenz 11y ago

What's great about merely preserving is that as long as we can preserve "indefinitely", the probability of future tech being able to recover the brain approaches 1.

stcredzero 11y ago
Assuming civilization doesn't collapse and the human race doesn't go extinct before becoming "The Progenitors."
ryanhuff 11y ago
Perhaps, but that's not helpful if the probability of the infrastructure to support the preservation (family who cares, businesses, or even civilization) surviving to reach that point approaches 0.
- daenz 11y ago
  Then it's not indefinite preservation :)
AnimalMuppet 11y ago
But, see, until someone successfully recovers, we don't know if we successfully preserved enough for a successful recovery.
wlesieutre 11y ago
Alternately, all the people who would have been working on solving those problems say "I'll get my brain preserved so I can wake up and live in the awesome future after someone else solves how to thaw me!"
Houshalter 11y ago
That's the awesome thing about cryonics. It's like forward time travel, an ambulance ride to the future. We have found organisms almost perfectly preserved for thousands of years in far worse conditions, including seeds that were able to grow and living viruses and bacteria. As long as the synapses that make you you are preserved, then a sufficient level of technology could revive you. Whenever cryonics comes up on HN there is usually a lot of negative comments. It seems "weird" and that really repels people. That was my first reaction to it. As a kid I saw a photo of a cryonics facility in some magazine. A bunch of metal tubes with frozen dead bodies inside. I thought it was really creepy and disturbing. Pictures of thawing rabbit brains aren't exactly enticing.
Retric 11y ago
Analog systems decay even at low temperatures.

nxzero 11y ago

Thanks; kills me how corrections are placed at the bottom of a story by some pubs.

zck 11y ago

From criticisms I've read of freezing a brain by infusing it with aldehyde, it destroys things necessary for brain function, such that it will be impossible to bring a brain frozen this way back in the future. P.Z. Myers^1 has said (http://freethoughtblogs.com/pharyngula/2016/01/29/how-can-you-protect-a-brain-by-destroying-it/ http://freethoughtblogs.com/pharyngula/2016/01/29/how-can-yo...): >I was fixing zebrafish brains with a cocktail of acrolein, glutaraldehyde, and paraformaldehyde in the 1980s, trying to capture detailed images of synapses in the spinal cord. It worked pretty well, too. They know what they are getting out of this: an aldehyde-preserved brain. >What I didn’t do with my experiments in aldehyde-preserved brains was claim that I was preserving all the information necessary for nervous system function. I was quite aware that I was chemically nuking all the proteins in the tissue; I was washing out most of the chemistry; I was destroying most of the physiological information to preserve a structural skeleton of what was there, so I could see the physical arrangement of the pieces. Nothing more. And later: >The pattern of synaptic connections is an essential part of the story, but it is not sufficient. A simple counterexample: consider the effect of MAO inhibitors and various antidepressants. They modulate the activity of the brain by affecting the intercellular concentration of neurotransmitters. ... > These things are all destroyed by fixation. The information is no longer there. > If this organization is so confident that they have preserved all the necessary information, I’d like to know why they’re playing around with just the first step of the problem, doing so in impractically complex organisms, and not working on the necessary step of recovering that information. That’s the real test. > Take a simpler organism, like a fruit fly or a nematode. Kill it, fix it, freeze it, vitrify it. That should be trivial at their tiny scale. Then rebuild a fly brain from the extracted information and show me that it still knows how to walk, fly, eat, court, and mate. It's reasonably convincing [1] I know he's considered somewhat controversial, but he's a biologist here speaking a sub-topic in biology he's worked in. Even if you don't like him, this can't be dismissed out of hand.

Houshalter 11y ago
The synapses are the important part. The other information can be inferred or reconstructed. But your memories and behaviors are stored in the connections and weights of synapses. His test is extremely unrealistic. No one is claiming to have the technology now to be able to revive cryopreserved brains. All we can do is try to preserve as much information as possible so future technology will have more to work with.

dang 11y ago

Ok, we changed the title to incorporate that.