When the group is remembering the crazy things Chang has done, Chang is shown snorting corn chips and he says "I said hot damn!"
This is a reference to Uma Thurman's character snorting cocaine in Pulp Fiction (1994).
Annie reacts to Abed's impression of Don Draper of Mad Men. Alison Brie played Trudy on Mad Men (2007).
Dr. Heidi says, "I think I've heard everything I need to hear in order to make a decision." Guest star John Hodgman often says something similar as he prepares to decide the verdict in his "Judge John Hodgman" podcast.
Abraham Benrubi makes an uncredited appearance as an orderly, much like the character he played in ER (1994).