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Check out Signing up your relatives.
Best of luck, and all my sympathy.
To quote a discussion of long term memory and the specific synaptic changes that take place from Molecular Repair of the Brain:
What, exactly, might these changes be? Very strong statements are possible in simple "model systems". Bailey and Chen, for example, identified several specific changes in synaptic structure that encoded learned memories from sea slugs (Aplysia californica) by direct examination of the changed synapse with an electron microscope[36].
"Using horseradish peroxidase (HRP) to label the presynaptic terminals (varicosities) of sensory neurons and serial reconstruction to analyze synaptic contacts, we compared the fine structure of identified sensory neuron synapses in control and behaviorally modified animals. Our results indicate that learning can modulate long-term synaptic effectiveness by altering the number, size, and vesical complement of synaptic active zones."
- "Morphological basis of long-term habituation and sensitization in Aplysia" by Craig H. Bailey and Mary Chen, Science 220, April 1, 1983, pages 91-93
In response to
Plastination is maturing and needs funding, says Hanson
A few comments:
1) Sign up for cryonics now. Do not delay because you think "Plastination might be better someday in the future".
- No one is offering plastination now, and you can die now.
- It's not clear when, if ever, anyone is going to offer plastination.
- It's not clear that plastination, if actually offered, will actually be better than cryonics.
2) With chemical preservation, good vascular perfusion is critical. Brain tissue which is not perfused is lost.
3) With cryopreservation, good vascular perfusion results in excellent preservation by vitrification. Brain tissue which is not perfused is still preserved.
4) Most of the costs for neuropreservation are from the up-front logistical and surgical costs. If you want minimal ischemic time and good vascular perfusion for chemical preservation you're still going to have to pay most if not all of those costs.
Ok, now we are squeezing a comment way too far. Let me give you a fuller view: I am a neuroscientist, and I specialize in the biochemistry/biophysics of the synapse (and interactions with ER and mitochondria there). I also work on membranes and the effect on lipid composition in the opposing leaflets for all the organelles involved.
Looking at what happens during cryonics, I do not see any physically possible way this damage could ever be repaired. Reading the structure and "downloading it" is impossible, since many aspects of synaptic strength and connectivity are irretrievably lost as soon as the synaptic membrane gets distorted. You can't simply replace unfolded proteins, since their relative position and concentration (and modification, and current status in several different signalling pathways) determines what happens to the signals that go through that synapse; you would have to replace them manually, which is a) impossible to do without destroying surrounding membrane, and b) would take thousands of years at best, even if you assume maximally efficient robots doing it (during which period molecular drift would undo the previous work).
Etc, etc. I can't even begin to cover complications I see as soon as I look at what's happening here. I'm all for life extension, I just don't think cryonics is a viable way to accomplish it.
Instead of writing a series of posts in which I explain this in detail, I asked a quick side question, wondering whether there is some research into this I'm unaware of.
Does this clarify things a bit?
You'll need to read Molecular Repair of the Brain. Note that it discusses a variety of repair methods, including methods which carry out repairs at sufficiently low temperatures (between 4K and 77K) that there is no risk that "molecular drift" would undo previous work. By making incredibly conservative assumptions about the speed of operations, it is possible to stretch out the time required to repair a system the size of the human brain to three years, but really this time was chosen for psychological reasons. Repairing a person "too quickly" seems to annoy people.
You might also want to read Convergent Assembly. As this is a technical paper which makes no mention of controversial topics, it provides more realistic estimates of manufacturing times. Total manufacturing time for rigid objects such as a human brain at (say) 20K are likely to be 100 to 1000 seconds. This does not include the time required to analyze your cryopreserved brain and determine the healthy state, which is likely to be significantly longer. Note that some alterations to the healthy state (the blueprints) will be required prior to manufacture, including various modifications to facilitate manufacture, the inclusion of heating elements for rewarming, and various control systems to monitor and modulate the rewarming and metabolic start-up processes as well as the resumption of consciousness.
After you've had time to digest the paper, I'd be interested in your comments. As Ciphergoth has said, there are no (repeat no) credible arguments against the feasibility of cryonics in the extant literature. If you have any, it would be most interesting.
As a neuroscientist, you might also be amused by Large Scale Analysis of Neural Structures.
For recent work on vitrification, I refer you to Greg Fahy at 21st Century Medicine.
In response to
Let's create a market for cryonics
The Alcor FAQ has a question and answer relevant to this discussion:
Q: Why haven't more people signed up for cryonics?
A: People don't sign up for cryonics because: it's not traditional, they're skeptical of anything they haven't seen work, it costs money, they're afraid of what their friends might think, they live in denial of their own death, they don't want to think about the subject, they procrastinate, they don't like life well enough to want more of it, or they are afraid of a future in which they may be alienated from friends and family and a familiar social environment.
Typical Alcor members (if any Alcor member could be called "typical") tend to be highly educated independent minded people who enjoy life and think cryonics has a reasonable chance of working. They pay for it with life insurance and think the future is likely to work out pretty well. They often have friends or relatives who are Alcor members. They expect Alcor to revive them using nanomedicine and expect to continue their lives with as much passion and joy as today — only with much more amazing technology.
I find it difficult to fathom why anyone would want to bring along a broken-down old body which is going to have to be replaced anyway.
Even assuming that making a new body is better than fixing the broken one (quite likely especially if ems are included in “new body”), how would its nerves (or equivalent) be connected to the repaired brain without a template of where each of the old nerves went? I was under the impression that the neural system, like the circulatory system, is “the same” between individuals only on the large scale, and individual fibers grow more or less randomly, like arterioles, the brain learning the positions of everything during growth.
I can well imagine almost-AGI level machines able to deduce most or maybe all of these based only on watching the effects of gentle prods to the inputs on unconscious brains, but with only human-level intelligence, even with em technology and fantastic (but not AI) computers I can’t quite see how you could do it without participation from the patient, and thus subjecting them to what I imagine might be described as “hellish maelstrom of the senses” for a quite long time.
(I don’t expect definite answers, of course—like the rest of cryonics, if we knew all the details we’d be doing it right now. I just wonder if this was discussed somewhere, and perhaps there’s something I’m not aware of which makes it simple in principle given some plausible anticipated advances. Do we even know if it’s possible, looking at just a single random axon, cut at the neck, to tell whether it connected to a nociceptor or a proprioceptor, even knowing exactly where it goes and everything there is in the brain? I mean, other than prodding it and asking the patient what they felt.)
You might want to read Cryonics, cryptography, and maximum likelihood estimation.
Short summary: if cryptanalytic methods can recover the wiring of World War II rotor machines knowing only some input-output pairs and with only limited information about the actual wiring, then similar algorithms should be able to recover the neuronal "wiring" between different cortical areas when we already have a wealth of information about that wiring plus a good knowledge of acceptable input-output pairs.
How many bytes in human memory? is a very brief article providing estimates of just that. Evidence from human learning experiments suggests that, after using a very good data compression algorithm, human long term declarative memory holds only a few hundred megabytes.
How much of that information is common knowledge, such as knowledge of the English language, memories from media such as books or television, or knowledge of local buildings and streets, is unclear.
Additional information specific to an individual could be gained from email, internet posts, and other personal electronic information and written records, such as diaries; as well as individual genomes, which will soon be ubiquitously available.
The modest information content of human declarative memory might be relevant to some of the discussions on this thread.
In response to
Alcor vs. Cryonics Institute
General advice: if you can afford it, sign up with Alcor. If you can't, sign up with CI.
If you want more information, I'd recommend the Alcor FAQs.
I should provide some context for my comments on Alcor's previous track record on creating endowments: we had just received a $7M bequest, had placed $3.5M into the Patient Care Trust Fund, and the Board had decided to put the other $3.5M into an Endowment and withdraw only 2% per annum, or about $70,000 per year, for Alcor's operational needs. Some members were feeling quite euphoric and were proposing that we spend some significant amount of the principal on various worthy projects, including reduced dues for said members and increased spending on certain pet projects. It seemed advisable to inject a note of sobriety into the discussion and to somewhat deflate the expanding expectations. While helpful, this bequest did not free us from the constraints of fiscal responsibility, and explaining why the Board was being so parsimonious with this windfall seemed appropriate at the time.
Given this context, I wouldn't interpret these comments as "disturbing".
In response to
How Likely Is Cryonics To Work?
There has been some discussion on this thread about who would revive you once you were cryopreserved, and how they would pay for it.
This is covered in the Alcor FAQ (which is really excellent, and well worth browsing):
Q: Who will revive the patients?
A: The short answer is "Alcor will revive them."
The third item in Alcor's mission statement is: "Eventually restore to health all patients in Alcor's care."
Reviving the patients is also required by Alcor's contracts with members: "When, in Alcor's best good faith judgement, it is determined that attempting revival is in the best interests of the Member in cryopreservation, Alcor shall attempt to revive and rehabilitate the Member."
Reviving the patients is also a duty of the Alcor Patient Care Trust: "At such time as Alcor deems that repair and revival of the Patients is feasible, the Trust shall expend whatever amounts of money are necessary to revive the Patients and reintroduce them to society, as long as on-going care of the Patients remaining in biostasis is not endangered. It is the intent of the Trust that such repair and revival proceed in such manner that ongoing Trust earnings reasonably can be predicted to provide for the eventual repair and revival of all Patients."
Financially, the Patient Care Trust should grow in real value over time — compound interest should eventually produce sufficient assets to cover the costs of revival. At the same time, as technology progresses the cost of reviving patients should decrease over time. Eventually, the ever increasing funds available in the PCT should be sufficient to pay for the ever decreasing costs of reviving the patients.
Socially, Alcor is a community. Some members of this community are alive and healthy, while others have been cryopreserved. This community forms an interconnected network of friendships and close ties. At any point in time the healthy members of this network have friends, relatives and loved ones in cryopreservation and will seek to revive them. Once revived, those members will in turn have other friends in cryopreservation, and they will in turn seek to revive them.
The plan is not for "them" to revive us. The plan is that we, the Alcor community, will revive ourselves.
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There is a helpful web page on the probability that cryonics will work.
There are also some useful facts at the Alcor Scientists' Cryonics FAQ.
The neuroscientist might wish to pay attention to the answer to "Q: Can a brain stop working without losing information?" The referenced article by Mayford, Siegelbaum, and Kandel should be particularly helpful.