brian@radio.toronto.edu (Brian Glendenning) (02/13/88)
An intersting discussion has come up on a local BBS. Some people there claim
that, contrary to what I have always believed, one is able to function
normally without any brain cells, or at least with very few.
When I expressed my disbelief I got the following in reply:
Peter Bennett (Asterisk BBS, Toronto, 416-826-3274) writes:
<[These articles centred around the work of] Dr. Lobner, an MD in Britain who
<specializes in hydrocephalic patients. These are people whose ventricles who
<have expanded enormously, and whose cranium is filled with spinal fluid. In
<most cases of hydrocephaly, pressure on the brain incapacitates the victim and
<in many cases, eventually causes death. With the advent of CAT scanning,
<Lobner examined some patients he thought showed signs of minor hydrocephaly
<but who functioned normally (one having an IQ of 136 and who was an honours
<math student). He found several cases, over 100 eventually, in which the
<subject had, instead of the normal 4.5 cm of brain tissue, less than a
<millimetre of tissue coating the inside of the skull. The cranium is filled
<with spinal fluid.
<
<The Psychology Today article, title forgotten, is by Lobner himself and he
<states it a little more dramatically, implying that these people do not need a
<brain at all. The article I read stated clearly that some of these people had
<*no* brain cells. I do not know whether this was an exaggeration or not, but
<it was unequivocal.
<
<I realize that there is a large difference between *no* brain cells and a
<layer of cells less than 1 mm thick. The article I read was much more recent
<than the articles I found yesterday, and definitely contended that people can
<function with no brain cells at all. It is difficult to say whether this is
<the result of uncovering subjects without brain tissue, or perhaps might be
<the result of some journalist getting carried away. I do know that the source
<I first saw was one that I trusted, and the article was convincing. [...]
Is this right? Does anyone have any information? A bibliography or good recent
reference would be great, but any information would be appreciated. I am
skeptical of this "no brain" idea, but could believe the position of another
respondent who said the research showed that people could live normally with
something like 10% of normal brain cells. On the other hand, since I'm an
astronomer with virtually no knowledge of this subject, I may be totally out
to lunch. What's the scoop?
--
Brian Glendenning INTERNET - brian@radio.toronto.edu
Radio Astronomy, U. Toronto UUCP - {uunet,pyramid}!utai!radio!brian
+1 (416) 978-5558 BITNET - glendenn@utorphys.bitnettale@pawl5.pawl.rpi.edu (David C Lawrence) (02/15/88)
I was always led to believe that what was the final cause of death for
all animals was hypoxemia (sp?), or lack of blood to the brain.
Which implies that you need th brain, with a good working supply of
blood, to survive.
But I suppose it is possible, and believable enough to me, that if you
so configured a human being with a vast network of machines which could
regulate the other processes necessary for sustained life (breathing to
oxidize blood, beating heart to circulate blood, working watse-removal
system, et al) then it would be possible for that human being to live
without a brain.
But there isn't much point to it.
And it sure wouldn't be a heck of a life.
*!*
"Those who find they have nothing to go out of their way for soon find they
have nothing at all." -- Tale Laslingis, during the Fourth History.
EMAIL: tale@rpitsmts.bitnet, tale%mts.rpi.edu@rpitsgw, tale@pawl.rpi.edu
THE HORN: (518)276-7214, (201)383-9414 during academic recess.
DISCLAIMER: Who needs disclaimers when it's USENET policy?geb@cadre.dsl.PITTSBURGH.EDU (Gordon E. Banks) (02/16/88)
In article <955@radio.toronto.edu> brian@radio.toronto.edu (Brian Glendenning) writes: > > >An intersting discussion has come up on a local BBS. Some people there claim >that, contrary to what I have always believed, one is able to function >normally without any brain cells, or at least with very few. > The hydrocephalics who function well, on autopsy have a thin cortical mantle which contains most if not all of the neurons used in cognition. The vast majority of severe hydrocephalics are severely retarded, however. The bulk of the brain substance does not consist of neurons, remember. Anyone who says you can have an I.Q. of 136 without any brain cells is an idiot.
msellers@mntgfx.mentor.com (Mike Sellers) (02/19/88)
In article <955@radio.toronto.edu>, brian@radio.toronto.edu (Brian Glendenning) writes: > [...] > <I realize that there is a large difference between *no* brain cells and a > <layer of cells less than 1 mm thick. The article I read was much more recent > <than the articles I found yesterday, and definitely contended that people can > <function with no brain cells at all. It is difficult to say whether this is > <the result of uncovering subjects without brain tissue, or perhaps might be > <the result of some journalist getting carried away. I do know that the source > <I first saw was one that I trusted, and the article was convincing. [...] > > Is this right? Does anyone have any information? A bibliography or good recent > reference would be great, but any information would be appreciated. I am > skeptical of this "no brain" idea, but could believe the position of another > respondent who said the research showed that people could live normally with > something like 10% of normal brain cells. On the other hand, since I'm an > astronomer with virtually no knowledge of this subject, I may be totally out > to lunch. What's the scoop? > -- > Brian Glendenning INTERNET - brian@radio.toronto.edu First, a few sources that may help: Aymlard, G. P., Lazzara, A., Meyer, J. 1978. Neurological Characteristics of a Hydroencephalic Infant. Developmental Medicine and Child Neurology 20 (2): 211-217 Dobbin, J., Sands. J 1973. Quantitative Growth and Development of the Human Brain. Archives of Disease in Childhood 48:757-767 Fishman, R. A. 1980, Cerebrospinal Fluid in Diseases of the Nervous System. Philadelphia: Saunders. Milhorat, T. H. 1972, Hydrocephalus and the Cerebrospinal Fluid. Baltimore: Williams & Wilkins. Also many good neurology texts will discuss hydrocephaly at least a little. I don't agree with most of the claims made in the article you referenced (and I hate to say it, but an article in Psychology Today carries just a little more weight than one in Reader's Digest does :-7 ). People definitely need brain cells to function. The examples give are either untrue or distortions, I'm sure (for example, the honors math student may have had trauma-induced, rather than cogenital hydrocephaly, which could have a more gradual deleterious effect on his/her intelligence and personality than if his/her brain had developed that way). To know a little more about situations like this, you have to understand a few things about neuroanatomy, and also understand that relatively little is known about its pathological limits and responses. The cerebral cortex is usually about 2mm thick (with some individual variation), and is scrunched and folded so that it fits inside the skull. Underneath the cortex, which consists almost entirely of small (local) neurons and the cell bodies of other neurons, is the so-called white matter, which is made up entirely of fibers going to and coming from targets in the body. So it isn't like your head is chock full of a mass of brain cells like a big sponge or something; most of the cells themselves actually live on the "outside" of the brain, with the afferent and efferent fibers taking up the bulk of the middle. In the white matter are the cerebral ventricles, which contain cerebrospinal fluid (CSF). CSF acts as a shock absorber, nutrient fluid, and probably as a messenger fluid for hormones, etc. An excess of this fluid due to blockage, or a malfunction in its manufacture or uptake, can cause excessive pressure on the cerebrum, often resulting in hydrocephaly. From what I've read, the white matter fibers are both pushed out of the way and/or severed (via degenerative stress), so this could definitely have an effect on the cortex and a person's behavior. It makes a big difference if this happens to you as an adult vs. as a child; in young children, the brain is still growing furiously and will not react well to the excess pressure from the ventricles. In these cases, the effects of the hydrocephaly are probably the most profound. Also within the white matter are the basal ganglia, which as a group are much like a smaller, evolutionarily older brain within the cerebrum. These structures seem to mediate many complex behaviors, including emotional responses, walking, writing, some phonation, and other programmatic actions. I'm not sure how much the basal ganglia would be affected by excessively large cerebral ventricles, but it is possible they could escape largely unharmed. These structures are often ignored by people discussing the brain, and yet they seem to be responsible for much of the coordination of our behaviour. If these remained largely intact while the cortex gradually degenerated, the most visible effects of the degeneration could be masked. That's about all I know about hydrocephaly. Maybe one of the med-student types could fill us in more on the effects of it on the basal ganglia, etc. The bottom line, though, is that you definitely need the bulk of your brain cells to function normally; I'd be very suspicious of someone who says otherwise without good documentation. -- Mike Sellers ...!tektronix!sequent!mntgfx!msellers Mentor Graphics Corp., EPAD msellers@mntgfx.MENTOR.COM "Never confuse motion with action." -- Ben Franklin