An 18 year old woman presents with a very weird chief complaint: drooling. She's also has inappropriate uncontrollable grinning and slurring of speech. She is brought in by her college roommate who is very concerned. "Even though she's smiling, I think she's depressed," the roommate says. "She never wants to do anything, seems to have no motivation, and sometimes, thinks people are after her. Is she paranoid? Her personality's changed. And I think her grades are a lot worse." On exam, you note a tremor, rigidity, and a clumsy gait.
Challenge: What's your diagnosis?
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