When a person has been awake for too many days on meth and they can no longer can form proper sentences, words get jumbled up and you get tongue tied. Your thought process is slim to none causing you to say things without thinking, focusing and concentrating are unrealistic goals, and your memory is completely shot. Usually a sign it's time to put the meth down and go the fuck to sleep.
"Damn dude Jessica's really got meth brain today doesn't she?"
"Yeah she's gotta lay off the meth for a while"
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