Since the first presidential debate there has been much talk about cognitive tests. Here’s what these tests look like and what they can and can’t measure. There has been much talk about the cognitive ...

Since President Joe Biden's poor debate performance last month, some Democratic lawmakers and political commentators are calling on him to take a cognitive test to illustrate his mental capacity.

Trump gets a lot of things wrong when he talks about cognitive tests. He recently bragged to journalists that he “aced” one, and said the doctors at Walter Reed told him no president had taken a ...