From PBS on "Experts Describe What Happens to Our Brains and Memories As We Age".

"There's actually a lot of abilities that remain stable or even get better with age(see comment)" - Dr. Charan Ranganath, U.C. Berkley

(continued from above) "So, for instance, knowledge, like the kind of knowledge that you would hope a president would have, that remains stable or can even improve. Likewise, you see things like compassion and emotion regulation that can be improving with age, or at least remain stable.

I think a lot of what people judge is based on surface characteristics that are dominated by confidence or by physical presence, rather than the more substantive issues." - Dr. Charan Ranganath, U.C. Berkley