Afişare Mesaje
2596
Discuții libere / Re: Natura omului
« : Noiembrie 02, 2012, 07:23:05 am »
Expresia din engleză vorbește despre conștiență în absența unei activități cerebrale MĂSURABILE. Nu absente, ci măsurabile, ceea ce e altă ciorbă.
A Reply to Shermer
Medical Evidence for NDEs
Pim van Lommel
http://www.nderf.org/vonlommel_skeptic_response.htm
Si raspunsul lui Michael Shermer (in ultima lui carte, The Believing Brain, care o citesc acum):
Citat
Sometimes trauma can trigger such experiences. In a 2001
study published in the British medical journal Lancet, Dutch sci-
entist Pim van Lommel and his colleagues reported that of 344
cardiac patients resuscitated from clinical death, 12 percent re-
ported near-death experiences. These included the full-on out-
of-body experience, a light at the end of a tunnel, and so forth.
Some of these near-death cardiac patients even described speak-
ing to dead relatives.
Dr. Mark Crisplin, a Portland, Oregon, ER doctor, reviewed
the original EEG readings of a number of patients claimed by
the scientists as being flatlined or "dead" and discovered that
this was not at all the case. "What they showed was slowing, attenuation,
and other changes, but only a minority of patients
had a flat line, and it [dying] took longer than 10 seconds. The
curious thing was that even a little blood flow in some patients
was enough to keep EEGs normal." In fact, most cardiac pa-
tients were given CPR, which by definition delivers some oxy-
gen to the brain (that's the whole point of doing it). Crisplin
concluded: "By the definitions presented in the Lancet paper, no-
body experienced clinical death. No doctor would ever declare a
patient in the middle of a code 99 dead, much less brain dead.
Having your heart stop for 2 to 10 minutes and being promptly
resuscitated doesn't make you 'clinically dead.' It only means
your heart isn't beating and you may not be conscious."
(Mark Crisplin, "Near-Death Experiences and the Medical Literature",
Skeptic 14, no. 2 (2008): 14-15)
Again, since our normal experience is of stimuli coming into the brain
from the outside, when one part of the brain abnormally gener-
ates these illusions, another part of the brain—quite possibly
the left-hemisphere interpreter described by neuroscientist
Michael Gazzaniga—interprets them as external events. Hence,
the abnormal is interpreted as supernormal or paranormal.
In addition to localized neural networks, hallucinogenic
drugs have been documented to trigger such preternatural expe-
riences, such as the sense of floating and flying stimulated by at-
ropine and other belladonna alkaloids. These can be found in
mandrake and jimsonweed and were used by European witches
and American Indian shamans, probably for this very purpose.
Dissociative anesthetics such as the ketamines are also known
to induce out-of-body experiences. Ingestion of methylene-
dioxyamphetamine (MDA) may bring back long-forgotten mem-
ories and produce the feeling of age regression, while dimethyl-
tryptamine (DMT)—also known as "the spirit molecule"—caus-
es the dissociation of the mind from the body and is the hallu-
cinogenic substance in ayahuasca, a drug taken by South American shamans.
People who have taken DMT report "no longer
have a body," and "I am falling," "flying," or "lifting up." Neu-
roscientist David Comings drew out the larger implications of
such hallucinations for die relationship between our rational
and spiritual brains:
The psychedelic drugs like DMT often produce a sensation
of "contact," of being in the presence of and interaction
with a non-human being. Highly intelligent and sophisticat-
ed test subjects who knew these feelings were drug-induced
nevertheless insisted the contact had really happened. The
temporal lobe-limbic system's emotional tape recorder
sometimes cannot distinguish between externally generated
real events and internally generated non-real experience
thus providing a system in which the rational brain and the
spiritual brain are not necessarily in conflict.
These studies, and countless others, continue to rain blows
down upon the dualist head that brain and mind are separate.
They are not. They are one and the same. The brain, and the
brain alone, is the source of our beliefs, and thus the template
for our understanding of reality. The neural correlates of con-
sciousness and subconsciousness elude us personally and can be
gleaned only through careful scientific research using sophisti-
cated tools such as brain scans and electrical stimulation of
brain regions. As science marches onward it is inevitable that
the paranormal and the supernatural either will be subsumed
into the normal and the natural, or will simply disappear as a
problem to be solved.
Deci nu.