I've yet to see any evidence on the effects of calorie restriction on humans. Mice are quite different from us, and all evidence on calorie restriction I've seen was done on mice.
Some human research is listed here.
I never saw any study on the effects of calorie restriction to attention, reflexes and cognitive abilities.
There are plenty of studies on that - e.g. start here.
I recently came out against paleo in the open thread, and realized that I probably haven't yet heard the strongest arguments in favor of a paleo diet. So, what are said arguments?
EDIT: Or more generally, why should I eat less carbohydrates and more protein / fat?