Good evening. I'm Jim Acosta in for Laura Coates on this Monday night, 10 days out from the highly anticipated debate between

Joe Biden and Donald Trump right here on CNN and tonight a moment from this

past weekend is leading to questions about a candidate's mental fitness for office.

I took a cognitive test and I aced it.

Dr. Ronnie.

Dr. Ronnie Johnson.

Does everyone know Ronnie Johnson, does everyone know Ronnie Johnson, congressman from Texas?

It's actually Dr. Ronnie Jackson, not Johnson.

Donald Trump, they're forgetting the name of his own doctor while challenging

Biden to a cognitive test. If you've been watching right-wing media that's

probably not the moment you were expecting us to play. No, instead it is this

clip that they've been circulating to question Biden's mental fitness.

It's Biden at the end of his Los Angeles fundraiser from over the weekend.

You can see him standing before a cheering crowd and then Barack Obama grabs Biden by the hand and

walks with him off stage. The New York Post, among others claiming Biden froze.

There is no evidence of that but Fox and others have been replaying this on a loop claiming otherwise

For his part Mark Cuban weighed in saying quote both candidates are old very old

They are both are going to have senior moments,

misremember, forget things, and have physical frailties.

He adds, one is great at sound bites,

but also thinks in sound bites.

The other is awful at sound bites,

...