[solveit]

Do they become mostly useless, or do they act erratically but effectively, as some sleepwalkers are known to do? For instance, some people are capable of driving while asleep. I imagine it's not outside the realm of possibility that a sleepwalking president could operate mechanisms that will start a war.

[ezzzzz]

Apparently my comment upset some people, I want to reiterate I was not insinuating anything about the President's current cognitive state, just stating it's something to look at. Both Sanders and Biden are tiptoeing on octogenarian status, making this concern as much of a consideration for them, or any other future president of an advanced age.

Anyway, to answer your question, I'm just a layperson, so I can't speak to exactly what is happening 'under the covers' when someone in the early stages of dementia experiences an acute episode. Trying specifically to recall my experiences as a caregiver, I'd say there is just a general confusion. They would seemingly not be aware of things like time (i.e. what year), no idea where they were or why (my experience was working in homes and in a hospital as a pca), no idea who I was, no idea who family members were, etc. Asking for deceased loved-ones was pretty common, they might even try to call them on the phone. It's all pretty variable. The point is, it's not hard to reason that having anybody in such a state being in charge of military power is a bad idea.