Here Megan Fox demonstrates a great example of an "Inward Lip Roll". This is a very common facial expression and often missed and discounted. It's a valuable tell and very indicative of increased anxiety. It often has a significant component of anger and an indication that the "temper fuse" is growing short and very possibly a verbal display or a more overt physical sign of anger will soon be heard/seen. A helpful way to think of the inward lip roll - is it's a signal that a person is trying to summon up more patience and/or simultaneously trying to calm themselves. The lips are an extremely sensitive tissue and touching one or both with the hand, fingers, tongue, teeth or manipulation with the other lip is an example of a Manipulator/Adaptor/Pacifier (MAP).
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