Body language
Facial expressions

Facial expression is a part of body language and the expression of emotion. An accurate interpretation of it relies on interpreting multiple signs in combination – such as the movement of the eyes, eyebrows, lips, nose and cheeks – in order to form an impression of a person's mood and state of mind; it should always be additionally considered in regard to the context in which it is occurring and the person's likely intention.

While facial body language can be interpreted as a sign of genuine emotion, a lack of it may suggest a lack of sincerity. For example, a lack of wrinkles around the eyes may suggest a potentially fake smile. At one point, researchers believed that making a genuine smile was nearly impossible to do on command. More recently, however, a study conducted by researchers at Northeastern University found that people could convincingly fake a Duchenne smile, even when they were not feeling especially happy.

The action of the pupil corresponds to mood, and it can communicate the mood of a person when it is observed. For instance, the research found that the person has no control over his pupils and they expanded when someone was interested in another person, or when they were looking at something. Normally, one's eyes need to instinctively blink at around 20 times per minute, but merely looking at a person the viewer finds attractive can make this rate faster.

Studies and behavioral experiments have shown that facial expressions and bodily expressions are congruent in terms of conveying visible signs of a person's emotional state. This means that the brain processes the other's facial and bodily expressions simultaneously. Subjects in these studies judged emotions based on facial expressions with a high level of accuracy. This is because the face and the body are normally seen together in their natural proportions and the emotional signals from the face and body are well integrated.
detectable_content:postscript