mental exhaustion
brain-fag

She was more concerned with her mental and physical exhaustion.

They didn't want him to sleep; exhaustion, physical and mental, was their objective.

He could smell mental exhaustion on himself like body odor.

Yet some workers talked of exhaustion - both physical and mental.

One explanation for this change in the artist's work is his physical and mental exhaustion.

Obviously he had succumbed to total exhaustion, both mental and physical.

The men do not understand his state of mental and physical exhaustion.

When we meet him, Reardon is in a state of mental exhaustion.

None of the Five had suffered anything except mental exhaustion.

He seemed on the point of physical and mental exhaustion.