the brain

[simoneee]

Does anyone knoe why the brain is wrinkly?

[Grunty]

The cerebral cortex of the human brain is highly convoluted, meaning it has many folds and creases. These convolutions allow a large surface area of brain to fit inside our skulls. Because of this brain shape, our brains can have billions of neurons and we can still have relatively small heads! Many animals do not have brain shapes like ours. Instead, their brains are smooth, with no sulci (grooves) or gyri (the bulges seen on the outer surface). However, in a new Science paper, Anjen Chenn and Christopher A. Walsh show that the normally smooth mouse brain can become folded and convoluted, much like human brains, if the production of a certain protein is changed.

http://faculty.washington.edu/chudler/betac.html

[dilligaf]

Cos its old. When you get old you get wrinkly. I should know.

[Octavius]

Because it is pickled inside your head

[Grunty]

Yes, you are right Octavius.  I was being silly.  If I had been in my cynical, provocative mood I would have said because only wrinklies use them, it's an appropriate shape for them.

[Octavius]

If you were being silly Grunty, you would have said why mens brains needed a foreskin.

[MargeB]

cos u walk. and think.

Grunty is right. To explain the limitation on head size, you need to take into account the fact that we walk. If you walk, you need a pelvis arrangement that is a bit smaller. Even at that, birth is a real pain. And on top of that, you need to rear a kid for 12 years before 'maturity'. To get even more in, as said, you make it wrinkly.

I understand that the gyri and sulci fit quite nicely into grooves in the 'pia/dura' mater that surround them on your head.

Which is why I'm against boxing. Your brain is getting on fine, thanks very much, without the gyri and sulci being bashed into their sharp fittings.