blank brain 

When you are so stoned and don’t wish to feel emotions so you just zone out.

Yo dawg is she good she looks like she went blank brain

blank brain by Blakley January 6, 2021

black brain 

The loss of brain cells due to the excessive use of marijuana, resulting in getting stuck on a word or thought

Dude that girl was rambling on, def black brain

black brain by Janet flight August 31, 2017