Honors mathematics student has only 10% of normal brain volume. How can this be true?

So, apparently, mathematicians don’t make good zombi food. This is important to know.

Barry Beyerstein’s remarkable “Whence Cometh the Myth that We Only Use 10% of Our Brains?” among other things touches on Lorber’s research, particularly some of the more sensationalized presentations of it.

In PDF form (see p. 14 and beyond),


Roger Lewin’s report on Lorber’s research, “Is Your Brain Really Necessary?” (Science 210: 1232-1234, 1980; mentioned in the link in the OP) also provides a helpful analysis of Lorber’s claims. Lewin mentions a paper Lorber delivered to “a conference of pediatricians” on whether, Lorber offered rather tongue-in-cheek, the brain was really necessary. I haven’t been able to find a reprint of this presented paper, except that it might have been published later in *Nursing Mirror * (152: 29-30, 1981), a presumably somewhat-less-than-top-tier publication likely not read by even your average neurologist.

I can’t speak to this anecdote’s appearance in The Exorcist, but something quite similar appears in Stephen King’s Thinner, published in 1984. One character tells another,

I suspect tellings such as this appearing in popular works of fiction have done much to reinforce the misconception that we truly only use 10% of our brains.

As others have pointed out, this patient may have (or may have had) 10% of the mass of the average-sized brain, but what’s the evidence that this particular small brain contains (or contained) fewer brain cells than its normal counterpart?

– Tammi Terrell

Are you suggesting that the brain cells themselves have on average 10% of the mass of normal brain cells?


What percent of your brain did you use to deduce that? :slight_smile:

Does the average size of brain cells (or any cells) in different persons vary much at all? Are you claiming that the average size of brain cells in one person could be one-tenth of the average size of the brain cells in other persons? My impression has always been that the average size of cells in one individual of any one species is very close to the average size of cells in any other individual of that species, as long as one is comparing the same type of cell. Does anyone know more about this?

I didn’t see in this article where he was hydrocephalic or what his brain size is. Did you have other evidence that supports this?

As I said, I knew him, and many people in describing him called him hydrocephalic. I admit that I haven’t seen him for years. I never talked to him about his condition. Are there other conditions that cause the skull to bulge out like that?

No. But there’s considerable seeming “dead space” (which isn’t dead space at all, since – for example – all sorts of chemical mediators are released and degraded there) surrounding brain cells and in myelinated tracts that is malleable to compression over a considerable length of time and under the right conditions. (See, for example, the Nissl-stained section of primate primary visual cortex on the left of this image.)

I suspect that post-mortem evaluation of histological sections of compressed cortical areas *in such rare, functional hydrocephalic patients * show a very comparable number of cortical neurons to those of individuals with normal cortical appearance, though in much compressed layers of the cortex. (In other words, I think it likely that the ratio of neuronal number to neuropil volume is much higher in these rare individuals.) One would think it’s maintaining a normal neuronal number, numbers of synaptic contacts, and efficacy of synaptic transmission that’s crucial here for normal function.

In the end, we don’t seem to know whether the individal Lorber described has/had a normal number or cortical neurons or whether he only has/had 10% of the number most individuals possess. My experience in basic neuroscience research favors considerably the former over the latter.

– Tammi Terrell

If you find this case interesting, I would like to recommend a book published in 2007 called The Brain That Changes Itself, by Norman Doidge (MD). Written for laypeople but could teach almost all doctors (and did teach me!) that the brain is a lot more adaptable than previously thought. I got several take-home messages from the book that is going to change how I approach learning, aging, etc.

There are a reasonable number of people who have had large parts of their brains removed. There are some obvious effects (like poor coordination) and some more subtle ones (as demonstrated in the “split-brain” experiments), but you could pick out other aspects of the person’s cognition that are normal. A related question might be, what don’t people with non-normal brains do well, or what capabilities are compromised?

ETA: Bob55, I hope your son continues to do well.

I’ve read about hydrocephalic people before. Most of them have severe neurological problems, but some live surprisingly normal lives and aren’t aware they even have the condition until it is found through some unrelated event (like they have to have a head X-ray for some reason). There were a couple of cases in the early days where they autopsied a dead guy and found no brain, which caused more than a little confusion because the condition wasn’t really known back then.

I’ve heard that even among those who live normal lives, their IQ tends to top out at about 130, which isn’t at all shabby for someone whose skull is mostly water, but isn’t as high as normally formed brains either.

Alright, I can’t take the speculation anymore! marches off to Google Scholar

Note that most of the subjects in the available studies have been shunted since birth, and that’s how they know they have hydrocephalus and are thus available to participate in the study. So many of these folks are not as bad off as someone who wasn’t shunted. As this first study shows, before the emergence of shunting 75% of cases lead to death before adulthood.

I just picked a few studies that I found interesting. As you might expect, no, these folks are not typically without significant disabilities across the board, although some can fall into the normal range on a variety of measures.

I’ve seen it widely stated that the brain contains a large proportion of structural fat. Is this not true?

engineer_comp_geek writes:

> I’ve heard that even among those who live normal lives, their IQ tends to top
> out at about 130, which isn’t at all shabby for someone whose skull is mostly
> water, but isn’t as high as normally formed brains either.

Say what? Someone with an I.Q. of 130 isn’t as smart as someone with a normally formed brain? An I.Q. of 100 is average. You would only expect about one person in 40 to have an I.Q. greater than 130. I don’t know what study you’re quoting and I don’t know how many hydrocephalics it included in its sample. It may, for instance, only have included 30 such people. That would be typical of a scientific study. If none of those people had an I.Q. higher than 130, that would be typical of a group of average people. The person who I know, Nick Patterson, has an I.Q. of at least, say, 140.

alterego writes:

> As you might expect, no, these folks are not typically without significant
> disabilities across the board, although some can fall into the normal range on a
> variety of measures.

Nobody is questioning the fact that the majority of such people are profoundly retarded. The question is why some of them have normal intelligence.

By the most amazing of coincidences, I passed this guy on the sidewalk the other day in Harvard Square. I had no idea who he was, just that he had a somewhat unusual appearance – lumpy head and one eye closed up. Next time I run across him, I’ll tell him Wendell says hello!

There are a surprising number of cases where a hemispherectomy (literally removing half the brain) has been performed on kids and they turned out remarkably well. Here is one such story and the young woman is headed to college (given the date of the article likely well through college at this point).

A Google turns up a surprising number of stories like this. In this article they mention the girl regained the ability to speak two languages fluently and the doctor said such recovery was not unusual in their experience with 65 such cases.

I am not suggesting your son needs anything as dramatic as this kind of surgery but offer it to let you know the brain seems much more remarkable in its ability to recover and adapt from seemingly overwhelming damage. However, children seem more able to recover than adults. I am not so sure an adult could adapt after something so dramatic (not sure).

:stuck_out_tongue: Those stupid dutch people.

Because “normal intelligence” has very little meaning. Intelligence is not a blanket term. These folks have deficiencies in some areas and are normal in the sense that they are average to above average in others. Notably, their intelligence quotients do not follow the typical distribution, so no, they are not “normal”.

Am I allowed to mention how cool it was to have posts on brain anomalies from someone calling herself Tammi Terrell?


I wonder what distribution my own intelligence quotient follows. I assume its normal, but who knows? I should check.