The pro-McCain argument that older is better.

Ronald Rotunda makes the pitch:

Older people can use both sides of their brain together, which gives them an advantage. As [Dr. Gene Cohen, director of the Center on Aging, Health & Humanities at George Washington University] notes, a 75-year-old historian can “run circles around” a 25-year-old Rhodes Scholar studying history. Older people continue to generate new brain cells if they are active and participate in events. Cohen says that age confers a “new senior moment—a creative moment.”

Of course, if the old person is vegetating on the couch, watching the Home Shopping Network, age confers no advantage, but that is not what John McCain has been doing. He has been exercising his brain and, like muscles, it improves with use. “Use it or lose it” applies to our brain as well as to our deltoids.

Older people can use both sides of their brain together, eh? I have some questions about that How do they know this happens? (Answer: MRI and PET scans.) Why is it better and not more like, say, needing to use 2 hands to carry something you find heavy?

I'm skeptical about these notions of right-brain creativity and left-brain analytical reasoning, but assuming the 2 sides of the brain do think differently and that some brain halves play better together, would it be better for a President to have a brain like that?

It's rather obviously that looking straight at the individuals — McCain and Obama — will give us better information about whose brain we want in the White House. But since there is a general prejudice against older brains and the people who think with them, it's helpful to know that they can be better.