recherchez un mot, comme blumpkin :
 
1.
To lose one's mind/marbles. Refers to when an individual forgets obvious things or makes easy mistakes, similarly to the symptoms of going senile.
'You're losing on yourself because you put your shoes in the fridge!'

Amy is losing on herself because she confused a person with a cat.
de Giant Mushrooms 1 juin 2011
 
2.
To lose one's mind/marbles. Refers to when an individual forgets obvious things or makes easy mistakes, similarly to the symptoms of going senile.

As defined by Peter Smith.
'You're losing on yourself because you put your shoes in the fridge!'

Amy is losing on herself because she confused a person with a cat.
de Giant Mushrooms 3 juillet 2011