In Hindi, there is an idiom "दिमाग का दही हो गया" (dimaag ka dahi ho gaya) which literally translates to "brain turned into yogurt". This is used when you're mentally exhausted and unable to think with your usual speed/clarity. Example situations:
- A student studying for a few hours.
- A person bored by listening to speeches all day, even though they weren't paying much attention.
Is there an English equivalent of this idiom?