
Well, clearly MENTAL tasks are not enough.
The Big Bang Theory Season 10, Episode 22

Then as a MENTAL exercise,
I invite you to figure out...
The Big Bang Theory Season 4, Episode 22

And with that MENTAL picture,
I think we're done for the evening.
The Big Bang Theory Season 4, Episode 4

I heard you had
some kind of a MENTAL break?
Westworld Season 3, Episode 8

You need to push your brain out of its
comfort zone and reach MENTAL exhaustion.
The Big Bang Theory Season 10, Episode 22