19 July 2012

Plastination 2

Plastination 2

Previously

I blogged about Plastination, a potential alternative to cryonics.

Luke's comment got me to write more (always a risk commenters take)

The biggest problem

The big problem in plastination is that it is hit-or-miss. What it preserves, it seems to preserve well, but in current SOA, whole sections of the brain might be unpreserved. The researchers who developed it didn't care about bringing their lab rats back from the dead, so that was considered good enough.

From a layman's POV, infusing the whole brain doesn't look harder than cryonics infusing the whole brain with cryoprotectant, but there could be all sorts of technical details that make me wrong.

So which wins, plastination or cryonics?

A lot depends on which you judge more likely in a reasonable time-frame: repair nanobots or emulation. I'd judge emulation much more likely. We can already emulate roundworms and have partly emulated fruit flies. So I suspect Moore's law makes human emulation in a reasonable time-frame much more likely than not.

Can we prove it?

One thing I like about plastination-to-emulation is that we could prove it out now. Teach a fruit fly some trick, or let it learn something meaningful to a fruit fly - maybe the identity of a rival, if fruit flies learn that.

Plastinate its brain, emulate it. Does it still know what it learned? And know it equally well? If so, we can justifiably place some confidence in this process. If not, we've just found a bug to fix.

So with plastination-to-emulation, we have the means to drive a debugging cycle. That's very good.

Difference in revival population dynamics

One difference that I don't know what to make of: If they work, the population dynamics of revival would probably be quite different.

In plastination-to-emulation, revival becomes possible for everybody at the same time. If you can scan in one plastinated brain, you can scan any one.

In cryonics-to-cure-and-thaw, I expect there'd be waves as the various causes of death were solved. Like, death from sudden heart attack might be cured long before Alzheimer's disease became reversible, if ever.

11 July 2012

Plastination - the new cryonics?

Plastination - an alternative to cryonics

Previously

I'll assume that everyone who reads my blog has heard of cryonics.

Trending

Chemopreservation has been known for some time, but has recently received some attention as a credible alternative to cryonics. These pages (PLASTINATION VERSUS CRYONICS, Biostasis through chemopreservation) make the case well. They also explain some nuances that I won't go into. But basically, chemopreservation stores you more robustly by turning your brain into plastic. There's no liquid nitrogen required, no danger of defrosting. With chemopreservation, they can't just fix what killed you and "wake you up", you'd have to be scanned and uploaded.

Are thawing accidents likely? Yes.

Cryonics organizations such as Alcor just wouldn't let you thaw, because they take their mission very seriously?
Without casting any aspersions on cryonics organizations' competence and integrity, consider that recently, 150 autistic brains being stored for research at McLean Hospital were accidentally allowed to thaw (here, here, here). McLean and Harvard presumably take their mission just as seriously as Alcor and have certain organizational advantages.

My two cents: Store EEG data too

In the cryonics model, storing your EEG's didn't make much sense. When (if) resuscitation "restarted your motor", your brainwaves would come back on their own. Why keep a reference for them?
But plastination assumes from the start that revival consists of scanning your brain in and emulating it. Reconstructing you would surely be done computationally, so any source of information could be fed into the reconstruction logic.
Ideally the plastinated brain would preserve all the information that is you, and preserve it undistorted. But what if it preserved enough information but garbled it? Like, the information that got thru was ambiguous. There would be no way to tell the difference between the one answer that reconstructs your mind correctly and many other answers that construct something or someone else.
Having a reference point in a different modality could help a lot. I won't presume to guess how it would best be used in the future, but from an info-theory stance, there's a real chance that it might provide crucial information to reconstruct your mind correctly.
And having an EEG reference could provide something less crucial but very nice: verification.