German Chancellor, Angela Merkel is showing a great example of a mild to moderate fear expression in this photograph. The most obvious signs here are noted in her mouth, jaw and the neck. Her lips are characteristically stretched backwards and down-turned at the corners. With more extreme fear the lips are more widely parted (often baring the lower teeth) and stretched back even further, giving a more pronounced downward curve to both the upper and lower lips. The jaw (mandible) often pulls dramatically backwards, but here it is only modestly expressed.
Chancellor Merkel's eyes are opened to a degree - that is for her normal. This example demonstrates a mild to moderate (and probably very brief - e.g. a "Microexpression" of fear) with essentially no involvement of the eyes. Sometimes, the eyes can be the primary display of fear though - even in subtle scenarios. In more dramatic examples of fear both the eyes and the mouth are involved. The eyes are in these cases are opened wider, often much wider, than normal. In such examples there is also a muscular-facial tension evident in the lower eyelids. Her eyebrow's which are only mildly elevated and slightly drawn together here - would be even further elevated and together with more severe levels of fear.
Pay close attention to Ms. Merkel's neck - all the muscles in the neck are tightened up. This action, along with a pulling back of the head, neck and jaw - can often create ridges of double and triple chins - which disappear when the jaw and neck are relaxed again.
I was not present at this conference, nor did I see video. While this is an excellent and unmistakable example of subtle fear, I don't know how long this expression lasted. This may have been a Macroexpression - lasting longer than 0.5 seconds, but it is an extremely common example of a microexpression. Microexpressions are unconscious actions and last as "long" as 0.5 seconds and are as fleeting as 0.04 seconds. Microexpressions occur with many emotions - not just fear. I see many examples, often hundreds or even thousands of these every day. A microexpression is a very reliable sign of an emotion and once you learn to recognize them, they will enable you read the hearts and minds of many a person.
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