Party Guest: So what do you do?
Jerry: I'm a comedian.
Party Guest: Are you? Let me ask you something. Where do you get your material?
Jerry: I hear a voice.
Party Guest: What kind of voice?
Jerry: A man's voice, but he speaks in German so I have to get a translator.
Party Guest: How come you keep tapping your head?
Jerry: It's a nervous tic. I'm on L-Dopa.
Quote from S03E10 - The Stranded