I found James “Flynn Effect” Flynn's essay in this month's Cato Unbound really fascinating. I especially liked this part:
The first implication of the new perspective is the benefit of persisting in cognitive exercise throughout life. There is the dramatic case of Richard Wetherill. He played chess in retirement and could think eight moves ahead. In 2001, he was alarmed because he could only think four moves ahead but he continued an active mental life until his death in 2003. Autopsy showed that his brain was riddled with the plaques and tangles that are characteristic of Alzheimer’s. Most people would have been reduced to a state of total confusion. This does not mean that cognitive abilities fail to decline with age. After all, at any given age, an athlete is better off for training. But however hard you train, your times will get slower as you age.
The brain is much more like our muscles than we had thought, even in the sense that specialized exercise affects different parts of the brain. Autopsies show that the brains of London taxi-drivers are peculiar. They have an enlarged hippocampus, which is the brain area used for navigating three-dimensional space. Here we see spatial abilities being developed without comparable development of other cognitive skills. To develop a wide variety of cognitive skills you need a wide variety of cognitive exercises.
I wonder what blogging is doing to my brain. More importantly, I think pretty persuaded by the Dickens/Flynn account of the brain-environment-brain-environment, etc. reciprocal causation feedback loop. But I look forward to seeing what Linda Gottfredson, who is more of a genetic determinist, has to say. Anyway, check it out.