Lose your marbles.
Lose your marbles.
To 'Lose your marbles' is to start acting irrationally or lose one’s mental capabilities. The imagery of marbles scattering uncontrollably parallels losing one's grasp on sanity or logical thinking, often used humorously to describe someone forgetting or acting unusually.
He seemed to lose his marbles after the intense pressure.
He seemed to lose his sanity under intense pressure.
After working non-stop, she felt she was losing her marbles.
After continuous work, she felt mentally exhausted.
Stressful situations might make you think you've lost your marbles.
Stressful situations might make you feel mentally unstable.