Nicole Kidman was on Jimmy Fallon's Tonight Show earlier this week. This was round two of reminiscing on "Jimmy's and Nicole's almost date" of years past.
One of the more obvious nonverbal signals you may notice is that Kidman and Fallon both blushed - Jimmy moderately - while Nicole did so profusely. While blushing is certainly not a requirement for sincerity, when blushing IS present, it's strongly correlated with an overall sincere personality (but not necessarily in that moment). Yet this was not the most interesting body language exemplified in this clip.
What follows is a more nuanced nonverbal display.
This image was captured at 5:28 - which was just before Jimmy Fallon first mentions Keith Urban (Kidman's Husband). In addition to her blushing, notice Nicole's backward leaning torso, closed eyes (a prolonged blink) and her crossed arms (all quite beta body language).
A few seconds later (above), Kidman leans forward as she positions the back side (dorsal aspect) of her index and middle fingers touching the base of her chin while she begins to disclose her surprise. Although Nicole is still projecting some beta qualities here (e.g., her right arm remains across her torso), she has definitely "dialed up her alpha" via this particular left hand configuration signifying a deliberate (planned) disclosure.
A moment later (above) these same two fingers straighten and their tips making contact with the underside of her chin as Kidman comes closer to her denouement. This change of finger configuration is indicative of increased adrenaline and its accompanying anxiety.
And in this final image - even closer to her "reveal" moment - only Nicole's index finger (aka "forefinger", which signifies the greatest alpha status and higher adrenaline) remains "standing". Here her anxiety also has grown even further. In this instant she's in a state of emotional dissonance - where she feels both "in control" - yet also nervous.
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