9 replies to this topic

[A941]

There is a Frog which is able to survive the winter as ice cube, its body's water is changed trough glucose, and its heartbeat stops, months later the ice melt, and its muscles move, weak electric impulses "start" its heart again.

http://www.wellesley.../afrogwood.html

I think that's very interesting, would it be possible to freeze living humans, and to "store" them for a unknown amount of time?
This would be much better than to freeze corpses.

[Elohim]

That's a very good thought, but I don't know anyone who would want to halt their own life because of a possibility that cryonic science could bring them back one day. It's a lot to risk.

[Bruce Klein]

There are some cases where halting ones life may be a better alternative than waiting for a natural death. Alzheimer’s, Parkinson’s, and other old age risks such as stroke may make waiting for a natural death to dangerous. Loss of oxygen and/or function may be irreplaceable to the brain cells. Thus, if you could plan the time of your suspension and have a team ready.. the possibility of successfully preserving the neuronal connections and the dendritic spines before hand would be much preferred. I'm hearing that 2hrs is about all the time one may have after death to preserve the brain. If so, planned suspension may be the only way to 'save' a brain/person from oblivion.

[Bruce Klein]

The important stuff.... neurons and dendritic spines.. thanks to Ocsrazor for pointing out the importance. - BJK

Development of Dendritic Spines
Sarah Ledoux

Quote:
Neurons have the capability of forming spiny outgrowths on dendrites that are associated with neuroplasticity. Stimulation, especially during post-natal development can lead to activation in the brain, referred to as Long Term Potentiation (LTP), associated with the growth of spines. These dendritic spines, which can number thousands to a single neuron, can have synaptic heads. Greater than 90 percent of synapses in the brain occur on them (1) . Through experimentation it has been found that a spine's glutamate receptors, calcium concentrations, and actin can affect its shape, length, and even presence on a dendrite. In general terms, how do dendritic spines develop and what do they affect in the brain? http://serendip.bryn...eb1/Ledoux.html



Quote:
Perhaps the most common synaptic specialization of dendrites is that which Spanish anatomist Ramon y Cajal referred to as "espinas", since they resembled the thorns on a flower stem. These spines are frequent on the dendrites of the principal cells of most brain regions, notably on the pyramidal cells of cerebral cortex and the Purkinje cells of the cerebellar cortex. For these cells, more than 90% of their excitatory synapses occur on dendritic spines. Therefore, spines may play an important role in learning and memory. http://synapses.bu.e...te/dendrite.stm

[Casanova]

This is the trickiest asspect of cyrogenics. When a person is revived how much of their memory, and learning, will be recoverable. The brain is so plastic, fluid, and delicate, at the micro-level, that Cyrogenics might end up reviving half-wits, amnesiacs, and cretins.
I really hope not. This is no laughing matter. Not even nanobots could help if too many connections, and configurations, are lost. A cloned brain, would be no good, either, because it would not be patterned with the life experience of the frozen person.

[DJS]

To freeze/cryogenically suspend a person before their natural death maybe an ethical threshold that our society is not yet ready to cross. Freezing someone while they are still alive is (atleast for now) effectively killing them. There are laws (which I disagree with) against such things.

On a differnt note, I have always wondered whether it would be feasible to preserve someone in a vacuum. There are many who say the freezing process will cause unrepairable damage to the brain. Isn't a vacuum free of bacteria/oxygen essentially suspended animation? Realitively ignorant on this subject. If anyone cares to enlighten me I would be much obliged.

[Bruce Klein]

A vacuum, a space void of oxygen and other floating molecules, would still have the molecules of the body itself.. thus the body would continue to break down.

[celindra]

The First Immortal dealt with cryonically suspending a live person. They took a dying girl to some state which allowed assisted suicide, put her under, and suspended her.

If I was facing impending doom, that's what I would do, rather than hope my local health professionals would adhere to my suspension arrangements.

[John Schloendorn]

Hehe, a guy from my lab recently put a crockroach into vacuum (not kidding!), and yea well first it shrank to half its size and then it detonated. He needed half a day to clean the pump. I do believe you would'nt want to do that to your dendrites...

This is because in a vacuum all things tend to evaporate in order to fill the empty space. Thats the main thing chemists are using them for.

[Bruce Klein]

Heh,

Thanks John for that lovely vision.