A few years ago the New York Times' science writer published a book called "The Secret Life of the Grown-up Brain: The Surprising Talents of the Middle-Aged Mind. She summarized the latest medical research, which was concluding that brain performance didn't really taper off as we aged, and there were actual spikes in performance in specific areas.
While there were smaller declines in things like remembering names, one theory was that what we know gets consolidated, allowing older brains to make greater leaps in logic more quickly. While older brains are distracted more easily, one study suggested people learn to compensate by using the left and right brain together to maintain focus and progress, and this results in bringing more "firepower" to bear on the tasks at hand.
While there were smaller declines in things like remembering names, one theory was that what we know gets consolidated, allowing older brains to make greater leaps in logic more quickly. While older brains are distracted more easily, one study suggested people learn to compensate by using the left and right brain together to maintain focus and progress, and this results in bringing more "firepower" to bear on the tasks at hand.