I am NOT saying that Joe Biden has this or making any kind of diagnosis. The best way to tease this out is would be with a formal cognitive evaluation.

Hi, neuropsychologist here. Mild cognitive impairment (or mild neurocognitive disorder) is the middle ground. This is when someone has cognitive deficits that go beyond what would be expected for normal aging, but don’t (yet) meet criteria for dementia (i.e. no significant functional impairment).