"When you read a script and it says in the script, 'He has obsessive compulsive disorder' and then you read two pages of a man repeating the same line over and over again… Not that it's easy for a writer to write that because he has his own thought process, but when you're an actor and reading that you say, 'How in the hell am I gonna say this and what is the driving force behind repeating something twenty times in a row and why the hell is he doing it?' So that brought me to work with Dr. Jeffrey Schwartz of UCLA, who is the leading physician on obsessive-compulsive disorder and treating it in a non-medicated fashion. He really explained to me what OCD is and the brain mechanism that goes into it and the sort of faulty gear shift, the sticky gear shift that happens when your mind obsesses on one thing and you don't listen to the other part of your brain that tells you you're being ridiculous. So, I worked a lot with him and a patient of his. I spent a few days with him, living around him and talking to him and really trying to find out why he had to repeat or do things obsessively. Then, reading every possible book I could on him and his life."