17 replies to this topic

[vidstige]

I wondered about something i think is an a important complication. This is the brain and the aging about the brain. The most, maybe everyone of the bodys tissues can be replays with the bodys own embryonal stemcsells, not today but maybe tomorrow can we transplanted or injected the stemcells in the body or even we can get the dna program the right signals to create the tissues in the body on the way that be growing in the own body.

But the brain is a big problem. Every cells who is dying is a memorycells for the souls/mind. How could we reverse the brain to the young stadium/level withaut that we destroy our memory in our brain. And how could we get the brain who is not smaller than compact as an oldyer brain than a younger one.

Vidstige

[Mind]

You are right that the brain brings special problems to solve... challenges to overcome. Perhaps new ideas will come forth at the Imminst conference on November 5th, with a special focus on the brain.

[bgwowk]

Memory loss is indeed a fundamentally difficult issue. Lost health and functionality are not *fundamentally* difficult problems because in principle you can always set right whatever is molecularly wrong with a mature nanotechnology, although that is still likely farther in the future than most enthusiasts believe. Hopefully methods of neurological rejuvination will be found sooner and simpler than brute force molecular repair. Stem cells are a beautiful example of a biological shortcut for doing things that formerly were only theoretically possible with advanced nanotechnology. Similar shortcuts may exist in the neurological realm.

Note also that lost memories are going to be an issue even for brains that are biologically immortal. There is only so much storage capacity in three pounds of tissue. People who believe that memory retention is important to their immortality will have to eventually grow to become life forms very different than they are today.

---BrianW

[bgwowk]

One often finds nanotechnology being used as the panacea for all biological challenges.

Something that doesn't exist yet is not a panacea. I think the correct way to view "mature nanotechnology" is as an upper bound of what is theoretically possible as determined by physical law. As a practical matter, solutions to almost all the problems people look to nanotechnology to solve will be solved by tools more mundane than machines designed one atom at a time. But if all else fails, the "mature nanotechnology" paradigm means that it eventually will be possible have atom-level control over analysis and repair of living matter. That's not a panacea. It's just an observation about what is and is not prohibited by physical law.

In my view this is a counterproductive notion.

That depends on the purpose for which the notion is promulgated. Certainly upholding mature nanotech as a reason to rest on laurels because all bioligical problems are going to be solved in a few decades is ludicrous. Also, arguing that quality of preservation in cryonics doesn't matter because "nanotechnology is necessary and sufficient" for cryonics to succeed is absurd. However it is legitimate to uphold mature nanotechnology as an argument that biological immortality is ultimately possible, and that technology can exist that is capable of fully utilizing the information that cryonics does preserve.

For nanotechnology to work - if indeed it is able to in the way it has been conceived - we must first have an exquisite understanding of the molecular processes we are seeking to modulate. Thus we should be seeking a "mature understanding of biology" rather than a "mature nanotechnology".

The two fields will of course develop in parallel, and eventually merge. Nanotechnological tools (in the broadest sense) will accelerate both understanding and control over biological systems.

Yet information encoded in this tissue is arranged in hierarchies of complexity we are only beginning to unravel at a very rudimentary level. Despite great advances in areas of physiology, genetics, neuroscience and developmental biology our understanding of cognition and memory has hardly progressed in the last 20 years. It appears that the fundamental science required to support such investigations does not yet exist and will require a fairly significant leap to explain higher brain function. Until we have such an understanding reproducing higher brain functions on silicon or other substrates is unlikely to occur.

For the record, I'm not an uploading enthusiast. I think the idea that in a few decades people will be able to transfer consciousness into silicon (why not vacuum tubes, which are just about as advanced?) is naive. When I say people will have to become different entities to retain very large memory stores, semiconductor electronics was not what I had in mind.

---BrianW

[advancedatheist]

We confabulate a lot of what we think we "remember" any way. According to some consciousness theorists, we even confabulate a false memory of "conscious" mental states about 300 milliseconds after unconscious brain processes do their thing. Given how much we depend on an imaginary past every day, maybe our identities don't require accurate memories of reality as much as we'd like.

[lightowl]

Thus we should be seeking a "mature understanding of biology" rather than a "mature nanotechnology".

Biotechnology and nanotechnology are complementary technologies. We should seek to mature understanding and utility of both. Nanotechnology will help us understand our biology just as understanding biology will help us advance nanotechnology.

One often finds nanotechnology being used as the panacea for all biological challenges.

Panacea can be perceived as a negative word. Nanotechnology is already and will continue to evolve as a powerful tool. Why this negative attitude towards its possibilities? Am I sensing a bit of bio-chauvinism?

About the brain:

I don't know how important it is to retain memory. Memories can easily be replaced and renewed by physical information. I am much more concerned about that elusive consciousness. It seems to me consciousness is a fluid state that can be altered both by chemical influence and by physical surgery. Is it possible that replacing cells will result in a period of impaired consciousness while the cells incorporate into the brain matrix?

[lightowl]

Whatever facillitates escape velocity is fine with me.

Indeed a healthy attitude. Let make sure to utilize all available tools and knowledge to that end as quickly as possible.

[John Schloendorn]

This brain aging problem stands to undermine all the efforts of SENS and other proposed theoretical frameworks for slowing, arresting or reversing senescence.

Some SENS proposals (allotopic expression, medical bioremediation) are "repair" strategies, i.e. ones that propose to rejuvenate an organism by rejuvenating its cells in situ. Such strategies are not necessarily required for cells that can be readily replaced with young ones. It looks like massive cell replacement is most difficult / least desirable in the neurons of the brain. So on the contrary, I would claim that SENS is designed to accommodate the special needs of the brain.

[bgwowk]

prometheus wrote:

If complete and consistent atom level control over matter is not a panacea - not only for the biological but all physical sciences - then I don't know what is.

Imagine I told you a tool could exist that was capable of reading and writing every byte on your computer hard drive (in fact such tools do exist). Would that be a panacea for computer problems? No, because complete knowledge of the operating system would be needed to make repairs. Would tools for reading and writing every byte, AND complete knowledge of what a normal operating system and file system was supposed to look like be a panacea for computer problems? No, because you could still have malfunctions and accidents causing irretrievable loss of data even after things are restored to working order.

So it is with "mature nanotech." That's why atom level control over matter is not a medical panacea. There will always be medical problems that are difficult or impossible to solve, even with atom-level control. But aging (defined as progressive breakdown of functional capacity) is not among them.

For perspective, I recommend the excellent essay by Thomas Donaldson

http://www.alcor.org...rymedicine.html

which is best summarized by the passage:

To understand medicine of the 24th Century, we have to understand the thin line between vulnerability and invulnerability. This line dominates our lives night and day. It is so important that we learn to walk along it without even thinking about it, any more than we think about breathing. And yet, whether we experience happiness or despair depends on where that line falls for us.

The most important point about 24th Century medicine is this: that line will fall elsewhere.

There are no panaceas, only changing problems.

But I'm even more intrigued by your belief in the manifestation of futuristic technology whose scientific principles have yet to be discovered.

There is a voluminous and growing literature on the principles of molecular mechanical machines. You would be surprised at the level of detail this has been worked out. The problem is building the tools to make the tools that will make the tools to make the devices. In my pessimistic view, it's a multi-generational technology bootstrapping problem, not one of basic principle. Then there's also the other side of story, which is the likelihood that most of the anticipated capabilities of molecular mechanical machines will also be achievable with biology-like devices based on diffusion chemistry (the Donaldson view).

Don't get me wrong, I'm all for futuristic technology but I think we may be sending the wrong message and distancing ourselves from the scientific community by emphasizing and overly relying on the achievement of anti-senescence through nanotechnology.

It depends on the context and the audience. Do I think nanotechnology is a good argument to use with health policy makers about how science can extend healthy lifespan of the present work force? No. Do I think nanotechnology is a valid argument to use here on Imminst with other Imminsters to convince them that biological immortality of the brain is possible in principle? Absolutely.

----BrianW

Edited by bgwowk, 31 October 2005 - 10:42 PM.

[spiritus]

I think that this problem needs to be taken on in a logical, methodical method.

body first, then worry about the brain.

The brain can survive up to 160 yrs+, it's the body that tends to wear out before 121

Pimp out that ride and by the time we are worried about the brain, we will have some soloution.

Honestly, any immortalist who thinks they will be living past 150 looking spotless is aiming at non existant targets. A lot of physical hardware will help support life at that age, I think a lot of computer hardware will be intergrated.

Once we begin losing memories, hopefully we will have it all backed up on our harddrives, if we didn't delete them for mp3 space..

[JonesGuy]

I'm going to look for papers on rejuvenating mental function by using allotropic stem cell therapies. But not right now.

If anyone has access to papers like this, could you post the reference please?

I know it's not SENS, but my hope for brain aging is actually stem cell therapy.

[spiritus]

The brain can survive up to 160 yrs+

Where did you find that gem?

heh probally not accurate. I heard it was capable of 150-160 years somewhere. Again, somewhere.