To most this is a hilarious (except perhaps to the First Lady) video captured today at a post-inaugural luncheon; John Boehner tells the newly sworn in Commander-in-Chief and his wife a joke. While he looks directly at the President, he taps Michelle on her upper arm (about two-thirds the way from the elbow to the shoulder) with the back of his fingers. Had Ms. Obama been looking at him, the Speaker of the House probably would not have made this physical contact. This moment of touch is captured in the image immediately below (at 0:03).
This next image (below at 0:06) shows a clear and classic nonverbal display of contempt towards Mr. Boehner. In the video, we see this facial expression twice (at 0:04 & 0:08). Note the left unilateral "snarl" with mid-face tension, her left lip curling up and although her eyes look in the Speaker's direction, her head barely turns towards him. We do not look directly at people who we don't like, don't respect or don't believe. This contempt display is initiated in the subconscious.
Another interesting and telling body language display seen clustered her, is Mrs. Obama pulls her arm closer, in a distancing, disapproval and defensive display (seen at 0:05).
The next photo show Michelle Obama in the middle of what most people see in this video - the "Eye Roll" (at 0:09). The eye roll is also a contempt display (sometimes coupled with an emotional tone of disbelief) - however, unlike the above noted contempt example, it is initiated consciously. At this moment, she fully intends to convey open disapproval to Mr. Boehner (and her husband). This bluntness is further demonstrated by the first lady also simultaneously shaking her head "no".
The president is showing sincere laughter- smile, while Boehner shows laughter mixed with a "fear-mouth" (a great example of emotional dissonance). At this moment John Boehner realizes he has crossed a line with the first lady - and offended her somehow, while Mr. Obama realizing this, touches her on her shoulder or upper back in an attempt to mollify her (at 0:09 - 0:10).
The image below is very telling as well (at 0:16- 0:18 in the video). Michelle Obama is still angry. Barack Obama is displaying a nose rub while John Boehner is committing an Inward Lip Roll (ILR) - both of which are forms of self-touching. In body language terminology these are known as MAPs (Manipulator, Adaptor or Pacifier) and signal clear anxiety on the part of both men.
In a nutshell, John Boehner made an attempt at humor and the President and the Speaker of the House both thought it truly was funny, but the Michelle Obama did not. In fact she was offended and displayed and felt contempt for Boehner (she almost certainly had already felt this towards the House leader for some time). The fact that John Boehner touched Mrs. Obama, and touched her particularly higher up the arm [a placed reserved for those whom we have closer relationships with - he would have done better to touch on the elbow, not above or below it (A. Pease)], acted to amplify her contempt - and it may in fact been the primary reason for Michelle's emotion here. The touch would have had the opposite effect if Michelle had good rapport with Mr. Boehner. Laughter is primarily a bonding experience. If Mrs. Obama had had some level of platonic affection for Mr. Boehner (clearly she didn't), and she thought his humor was truly funny - a combination of such touch-laughter would have engendered a greater level of bonding. When there is not a certain level of affection-familiarity, touching another person will often back-fire - although you will rarely see it exemplified so well on video.
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