Prof. Jean E. Fox Tree

I study how people communicate across different settings, such as using different communicative media  (video chat, face-to-face, audio-only, writing) or communicating to different kinds of addressees (two-person, three or more people, friends, strangers, intelligent virtual agents). As part of this work, I study the collateral signals produced when communicating spontaneously. These are signals beyond the conventional words uttered, and include discourse markers (words like you know and like), fillers (um and uh), repetitions and repairs (such as "she says well that's- we have to pay our- pay our own"), backchannels (uh huh), gestures, and prosodic information (the melodic pattern of an utterance). My theoretical and empirical work demonstrates that these phenomena are not only worthy of notice, they are of vital importance to successful communication in everyday conversation.


  • Psychology 125: Psychology of Language.
  • Psychology 126: Conversations.
  • Psychology 139H: Weird Science.
  • Psychology 193: Field Study.
  • Psychology 194B: Advanced Research.
  • Psychology 215: Production and Comprehension of Spontaneous Communication.
  • Psychology 224B: Language Proseminar.
  • Psychology 230: Colloquium.
  • Psychology 290E: Grant Writing for Psychologists.

Areas of Expertise

Psychology, cognitive science, and psycholinguistics, with a focus on the production and comprehension of spontaneous speech and writing.


Ph.D., Stanford University
M.Sc., University of Edinburgh
A.B., Harvard University