Our Brains Are Shrinking. Are We Getting Dumber?

I was taught, admitedly a long time agao that the Brain size was a rough indicator of intelligence in humans. What was more critical was the surface area of the brain. Hence the level of surface folds was a more important measure than the size or weight of the brain.

I just wanted to chuck that in.

Rgds
T

reply to post by unityemissions


A good point, but that was sort of in response to the "Our brains are getting smaller" statements in the title and following posts.

If the title had been "Cro-magnon had bigger brains than we do!" I wouldn't have said it, but the way the OP is worded, it sounds as though brains are currently shrinking, so...

As a few have sort of hit on a tangent - it's brain density that matters over brain size, as well as composition. Currently, our brains are about as dense as they can bet without our neurons undergoing some serious revisions (at present, if they get any smaller, their 'gates' will be flooded with noise and be unable to function). Having smaller neurons is a good thing, generally - it allows each neuron to be in contact with more neurons than if it were larger. This allows for more neural connections to be made - a far more significant factor in intelligence.

Another considerable factor is what the brain is actually made of. "white" matter can be thought of as bus-wires (it's not quite so simple, as "white" matter can perform processing of information) - it's mostly to transfer information. "gray" matter is what actually does most of the thinking. A skull full of "white" matter will be substantially less 'intelligent' than one full of "gray" matter. Of course - organization is everything, a functional mix of the two will be necessary to get much of anything done.