I don't think it's a laugh track and don't know how you can even tell. I've witnessed many times where the actors can't say their next line cuz of audience reactions. I can forgive a laugh track for on-location scenes like paintballing and stuff but I really don't think they'd use one for the on-set stuff which is the university cafeteria, the apartments and elevator and hallway, or the comic book store. I don't know what else is in the studio, if anything.
I do know that they tape the show multiple times and bring in a new audience each time to get new reactions, especially if some lines are flubbed and by the time they get it right it's not funny anymore, but every live-taping show does this kind of thing... Friends, Seinfeld, etc.
It's impossible to film EVERYTHING in-studio so I can forgive laugh tracks for on-location stuff.