Micro Expression

Micro expression is a brief, involuntary facial expression shown on the face of humans according to emotions experienced. They usually occur in high-stakes situations, where people have something to lose or gain. Microexpressions occur when a person is consciously trying to conceal all signs of how he or she is feeling, or when a person does not consciously know how he or she is feeling. Unlike regular facial expressions, it is difficult to hide microexpression reactions. Microexpressions express the seven universal emotions: disgust, anger, fear, sadness, happiness, surprise, and contempt. Nevertheless, in the 1990s, Paul Ekman expanded his list of basic emotions, including a range of positive and negative emotions not all of which are encoded in facial muscles. These emotions are amusement, contempt, embarrassment, excitement, guilt, pride, relief, satisfaction, pleasure, and shame. They are very brief in duration, lasting only 1/25 to 1/15 of a second.
As their name suggests, subtle expressions are very subtle. Even a slight tightening of the lips can be a reliable sign that someone is angry.
Examining the Face:
One way to understand facial gestures or behaviors is to divide them up by what they do, not whether they are mini, micro, or macro which does not take into account speed or in some cases lengthy, asymmetrical, or rigid presentations. The following is not a comprehensive list but if you focus on these five areas you will find it easier, in my experience, to identify how others truly feel or what they think:

Facial Gestures of Nervousness and Tension:
-   Furrowed forehead
-   Squinting eyes
-   Lip compression
-   Lips that are sucked into the mouth
-   Quivering lips
-   Quivering chin
-   Corners of mouth twitching or pulling oddly toward the ear very quickly

Facial gestures of Contempt or Disdain:
-   A smirk (corner of mouth tightens on one side, dimples, or pulls toward eye or ear )
-   Nose high haughty attitude
-   Rolling of the eyes
-   Looking dismissively askance
Contempt, incidentally, is not a sign of deception, it is seen in both the innocent as well as the liar. Contempt is often seen among the innocent when interviewed by those they deem to be of lower social status or whom they perceive as incompetent. You also see looks of contempt on the part of an occupied population toward their oppressors.
 
Facial Gestures of Dislike or Disagreement:
-   Pursed lips usually mean I don't like or I disagree (seen in babies as young as four weeks).
-   Nose crinkle (nose moves very quickly up as a shortened sign of disgust)
-   Upper half of lip on one side rises as does nose
-   Rolling of the eyes
-   Eyelid flutter (usually seen when someone says something we strongly disagree with)
-   Eyelids close fail to reopen for what seems a long time
-   Squinting of the eyes (think of Clint Eastward in a shootout)
 
Asymmetrical Facial Gestures:
Gestures that involve only one half of the face fall into this category:
-   Fake smiles
-   Smile involving only half the face
-   Person smiles but the eyes squint or show tension
-   Asymmetry also applies to discord between what is said with what the body is transmitting, such as saying, "I love you" with clenched teeth or a tense face.


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