I had a teacher my freshman year of high school tell me this.
She said that brains are wrinkly, because the more you learn, the wrinklier the brain gets to increase the overall surface area. Infants and mentally challenged people have smooth brains because they haven’t learned as much as the rest of us.
So, is this true? I’m kind of skeptical.
I doubt it, but I’m not sure…I’d like to second the inquiry.
No. There’s a grain of truth to this in that stupider animals (such as sheep) have much smoother brains than smarter animals, such as people or dolphins. (The increased surface area -> greater potential intelligence thing is an accepted theory, but on a species level rather than on a person to person basis.) However, brain geography doesn’t change so radically as to create new wrinkles after early development. Folding patterns are pretty set during initial brain development, in utero. Subtler stuff definitely changes during peoples’ lifetimes, but not general folding.
Yeah, wrinkles are on your brain just so you can fit more… well… brain into the skull.
Actually, the wrinkles represent a potential loss of volumetric crainial capacity.
What (ahem) convolutions do provide is a gigantic increase in available gray matter. This is where the dense six-layer deep neuronal connections are made that drive cortical processes.
Here is an excellent link to information about this critical structure. An interesting excerpt:
“If the gray matter, or cortex, were to be smoothed out on a flat surface, then it would occupy an area roughly 3 feet by 3 feet, one square yard.”
That’s a whole lotta neurons.
As GilaB mentioned, there is a correlation between wrinkles and intelligence. The wrinkles are thought to be caused simply by having a brain too large for the head, specifically the cerebral cortexes. The specie comparison is correct as well. Brain wrinkles differentiate us more from other animals than from Feynmann. In fact, scientists have genetically engineered mice brains to have human-like folds, though the effect on intelligence is undetermined. Brain Wrinkles
In normal people, there is a pretty “standard” plan from person to person. Fissures (large grooves), sulci (small grooves), and gyri (outward folds) vary, of course, but are pretty much the same in everyone.
I remember reading an article somewhere about a disorder that Einstein had that may have allowed his brain to have significantly more folds. I’ll search for that and post that if I find it.
identity theory is garbage.
I believe that Einstein may have had hypertrophy of the given brain regions associated with spatial perception and mathematical processing. I never heard that it was solely due to more cortical convolutions. In fact, it appears he may have been missing a wrinkle.Here is a link and excerpt:
“When Einstein died in 1955, pathologist Thomas Harvey quickly preserved the brain and made samples and sections. He reported that he could see nothing unusual. The variations were within the range of normal human variations. There the matter rested until 1999. Inspecting samples that Harvey had carefully preserved, Sandra F. Witelson and colleagues discovered that Einstein’s brain lacked a particular small wrinkle (the parietal operculum) that most people have. Perhaps in compensation, other regions on each side were a bit enlarged—the inferior parietal lobes. These regions are known to have something to do with visual imagery and mathematical thinking.”
In what sense is this a disorder? I just can’t picture the doctor saying “The prognosis isn’t good. You’re going to be another Einstein, and there’s nothing we can do to help.”.