Life Beyond Brain Death
Posted 18 Jul 2007 at 20:31 UTC by steve 
A Newsweek
article covers the changing definitions of death. It used to be that
when you reached "clinical death", that was it. Then it became possible
to restart the heart. Doctors moved on to declaring "brain death", when
cerebral function stopped. But it seems that even after the brain stops
working, all the information is still there and, provided
cellular death can be stopped or reversed in time, it's possible to boot
the brain back up. Normally, unrecoverable brain damage occurs within
five minutes but by lowering the body temperature,
doctors can significantly extend that time. More interestingly,
apoptosis and necrosis take time to destroy the information in the
brain, during which it may be possible to reverse the process or
cryogenically preserve the information
making up the mind and transfer it to a new receptacle; perhaps a
cloned brain or a robot. This leads to a new term: "information-theoretic
death" is the point at which the
physical structure of the brain succumbs to entropy and the mind can no
longer be reconstituted. This moral uncertitude as to when death occurs
is interesting in light of recent
suggestions that organ donation should be mandatory or done on an
"opt-out" scheme. Another
article suggests individuals be allowed to accept the legal
definition of death or define their own meaning. To
learn more about the endovascular temperature modulation techniques
described, see the Medical News
Today article on the subject.
This idea about cells committing suicide at reperfusion is interesting and if it can be prevented will cause us to face some difficult questions.
Still, the question about whether transferring info from a human brain to another container recreates the WHOLE person remains. If we are only meat-machines as some suggest then yes, but if there is another aspect to our lives that we are missing and not transferring then no. I'm thinking the later.
We may not be able to tell though by simply interacting with the new machine holding the copy since all the memories will be there, habits, and even desires, phobias, etc. But there might be a subtle, detectable difference that points to a yet-to-be identified aspect of our humanness.
RA
There was a sidebar in Newsweek noting the possibility that people will
see theological implications in the research (I assume a supernatural
soul is what you're hinting at with your more than meat comment).
More likely, the missing aspect of the new mind's behavior would be the
physiological drives produced by the rest of the human body. To some
degree that isn't a new idea, even among theologians. I recall reading
an essay by C. S. Lewis in which he talked about the
existence of believers in an afterlife and the drastic difference in
behavior he thought likely due to the lack of biological bodies with all
the associated physiological drives they produced. So, even assuming the
existence of a soul,
he thought you'd still see easily detectable differences in behavior.
Science seems to agree with Lewis to the extent that it's now fairly well
understood that many of the things driving our behavior, such as
emotions, are not entirely the result of our brain but the whole body.
So any extraction of the mind from the body, whether done by scientific
methods or supernatural ones, could result in significant changes in
personality. A cloned body might minimize the changes. Or in the case of
a robot body, synthesized inputs might be provided to simulate natural
bodily activity.
It's all science fiction and/or theological speculation for now of course.
I've wondered exactly how much of our actions are driven by are 'flesh' - hormones, pain, blood sugar, etc. I'm sure it varies person-to-person, and with time. It's obvious watching our kids grow up that this does indeed play a major role sometimes. For example, one of our children would be grumpy after drinking DrPepper. It took us a while to connect the two because of the delayed reaction.
You're right that these influences wouldn't exist if brain data was transferred to a machine. Maybe we would need to simulate some of these things to make interaction with the machine acceptable and understandable.
I don't know if this additional aspect of humans (soul) is supernatural or not. It could be more material than even us religiously-inclined might think. I keep my eye out for news and research into quantum physics, string theory, etc that might open the door in this area - I'm convinced it eventually will. The recent idea that the so-called dark energy (ie: fudge factor to explain expansion observations) is being hidden inside tiny dimensions is one example.
Perhaps we dont need all that much brain matter after all...
http://uk.news.yahoo.com/rtrs/20070720/tsc-uk-brain-tiny-1df2b7e.html