Introduction to terminologies
Face-to-Face (F2F): people facing each other
Synchronicity: (informal definition) moving in tandem; you just ‘click’.
Synchronicity: (webster definition) “the coincidental occurrence of events and especially psychic events (as similar thoughts in widely separated persons or a mental image of an unexpected event before it happens) that seem related but are not explained by conventional mechanisms of causality —used especially in the psychology of C. G. Jung” 
F2F synchronicity: this is how people take talk turn-by-turn when involved in a face-to-face conversation. This simple art can provide insightful feedbacks about people’s feelings during conversations especially conflict conversations.
Imagine for a minute that you are involved in an argument with someone — perhaps a close friend, your best friend, boss or significant other. Do you think your F2F synchronicity and facial expressions significantly change compared to when you’re catching up over a delicious-free-getaway dinner with red wine? (It’s okay if you still can’t imagine anything provided you get the point; you might want to re-read if you don’t.)
Background for question of interest:
Your best friend, a marriage counsellor, has just texted you saying that you should catch up at their place. You get there and after walking you to the living room, you’re left to a laptop playing a short movie while your friend fetches you lemon drink. The movie has a couple talking with each other but you can’t hear the sound because of bad audio. Your friend comes back saying “oh, I’m trying to infer the probability of a divorce based on their facial expressions and body movements.” “Oh wow, how?”, you ask. You definitely want in on this now because by now you already know about F2F synchronicity and facial expressions. What signs do you look for?
Question of interest:
If given a collection of videos showing couples engaged in a marriage conflict session, can you infer their emotional states by observing their F2F synchronicity and facial expressions?
You decide to start with yourself as an example. Hmmm, how do your F2F synchronicity and facial expressions change when you’re arguing (read: in conflict) compared to when you are collaborating. Perhaps, you may:
- talk while the other person talks,
- interrupt more often
- make more negative facial expressions — disgust, fear, anger, etc
- make increasing negative comments with time 
- make less positive comments
- have less eye contact by completely looking away etc
What other unlisted signs can you think of?
Disclaimer: I am not a marriage expert, neither do I in any way give marital counseling — in fact I am not married! I just find some of the literature about conflicts interesting and since marriage conflicts have been long studied, insights from this area could be used in other non-related aspects of life.
- Gottman, John Mordechai, and Robert Wayne Levenson. “The timing of divorce: predicting when a couple will divorce over a 14‐year period.” Journal of Marriage and Family 62.3 (2000): 737-745.
- Image source: http://www.feelmorebetter.com/marital-conflict/