Earlier this week golfing phenomenon Jordan Spieth was a guest on The Tonight Show. He was telling Jimmy Fallon a funny story about golfing with Bill Murray. From a body language perspective Mr. Spieth provides a fantastic example of nonverbal behavior commonly displayed - yet rarely discussed.
Jordan Spieth displays an asymmetrical smile throughout a good portion of this video segment. Nonverbal novices will say that asymmetrical smiles are not true smiles - and they would be correct a good percentage of the time - yet certainly not always. Spieth's smile is absolutely sincere.
Note Spieth's relaxed, noncontracted forehead muscles, his partially closed eyelids, the temporary concave-up furrows in his lower eyelids and, although this is more prominent on his left - Jordan's upward directed cheek muscles. We can see in some of the frames Spieth's lower teeth - because he is of course speaking while smiling, due to the camera angle and his slightly forward tilted head/neck.
As the mouth component of Spieth's smile grows, we see it become more symmetrical. It's also important to note that simultaneously the degree to which his eyelids are closing increases - also amplifying his smile.
Summary: Sincere smiles (aka Duchenne Smiles), as they crescendo, may often begin asymmetrically - but will increase in symmetry as the smile grows. This also occurs in the reverse direction - as the smile wanes.
See also:
Nonverbal Communication Analysis No. 3668: Donald Trump, Nigel Farage and The Brexit
Nonverbal Communication Analysis No. 3654: Hope Solo Calls Swedish Team "Cowards" after US Loss in Rio
Nonverbal Communication Analysis No. 3646: Melania Trump, Donald Trump, Visas and Citizenship
Nonverbal Communication Analysis No. 3625: Donald Trump Introduces Mike Pence as his "1st Choice" VP Pick (Not!)
Nonverbal Communication Analysis No. 3586: Barack Obama, Jimmy Fallon, Alpha-Beta Hybrids and Body Language
Nonverbal Communication Analysis No. 3562: Police Officer Tim Purdy and De-Escalation
Nonverbal Communication Analysis No. 3530: Justin Trudeau and Quantum Computing
Nonverbal Communication Analysis No. 3490: Conor McGregor, being a Plumber and LeBron James
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