In this Lip Sync Battle teaser-preview, Jenna Dewan Tatum displayed her dance and lip syncing skills performing Ginuwine's Pony - in a form of satirical one-upmanship - very obviously referencing (and using as a prop) her husband, Channing Tatum, and his performance in Magic Mike.
Yet when Jenna was speaking with L.L. Cool J afterward, as he said, "Is, is this like a typical night at the Tatum, household, or?"
Jenna answers, "Totally. We lap dance every night."
During L.L. Cool J's question, Jenna looks away from him (in this context that direction of gaze is very important) and raises her middle finger to her mouth.
She scratches her lip - to alleviate what was a highly probable and very real itch - (although secondarily generated by the relative anxiety she was experiencing - via the release of the neurotransmitter natriuretic polypeptide b [Nppb]).
This is a fantastic example of what in nonverbal lingo is known as a Partial Emblematic Slip.
An emblem (here the middle finger) is a nonverbal signal, the meaning of which has a highly specific and widely accepted meaning within a geographic region, country or culture. Some emblems are essentially universal - regardless of where they're used or who displays them.
This emblem however is not fully displayed - thus it is a partial one. And it's referred to as a "slip", because it's not fully conscious - and indeed, it may very well be entirely subconscious - ergo the body language nomenclature, "Partial Emblematic Slip".
We do not know the specific cause of it, and it will probably never be evident once this full episode is available for viewing, yet you can be sure that Jenna Dewan Tatum does not much care for L.L. Cool J.
See also:
Nonverbal Communication Analysis No. 3427: George Lucas regarding Star Wars, "I sold them to the white slavers" - Body Language
Nonverbal Communication Analysis No. 3094: John Kerry at the 51st Munich Security Conference - Mouth of Fear
Nonverbal Communication Analysis No. 3085: Olivia Munn Doesn't Like Johnny Depp - Just Listen to Her Body Language (Not Her Words)
Nonverbal Communication Analysis No. 2322: Jeb Bush & Matt Lauer - Which one is the Narcissist? Body Language Red Flags
Nonverbal Communication Analysis No. 3420: Bill Cosby's Mug Shot - Body Language Tells
Nonverbal Communication Analysis No. 3402: UFC 194: Conor McGregor and José Aldo - Octagon Post Fight Interview
Nonverbal Communication Analysis No. 3393: Syed Rizwan Farook, Tashfeen Malik, San Bernardino Shooting and Predicting Violent Behavior
Nonverbal Communication Analysis No. 3382: Donald Trump's Mask
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