Selena Gomez's appearance on the Tonight Show earlier today provides a great demonstration of a multitude nonverbal behavior tells (Fallon's original video has been removed from YouTube). One of these is discussed here.
Ms. Gomez says she believes ghost and spirits to be very real - and thus she has an app on her phone to detect their presence - and she demonstrated this for Jimmy Fallon and the audience.
After moving on to other subjects - after Selena channeled Johnny Cash while singing "Ring of Fire" - the signal on her Ghost Hunter M2 App sounded the alarm .... perhaps the Man in Black was singing a duet with her.
During 4:52 - 4:53 Ms. Gomez displays a classic facial expression of sincere surprise. Surprise is an emotion which is commonly feigned, yet if you know what to look for - you won't be fooled. Note how Selena's mouth opens primary with a vertical component. When people fake a surprise expression their mouths' open primarily horizontally - with the upper and lower lips being quiet taught. In sincere surprise, although very briefly - the lips are loose and plump.
Moreover a sincere surprise expression will not reveal teeth for the first second or two. Thereafter, as the surprise is replaced (partially [4:54] or fully) by other emotions - the teeth are usually revealed - but if the smile is sincere - they will be covered by the loose lips in the initial display.
Of course, during sincere surprise the eyelids also open wider. This too is often very brief and may be subtly opened (more difficult to spot in real-time) to extremely wide - depending on the level of surprise. Selena's eyes exemplify this prototypical "White and Wide" nonverbal signal - along with a simultaneous elevation of her eyebrows.
Is Selena's belief in ghosts 100% - or does she have some doubts? During this video, what is her primary anxiety tell?
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