Melos

Facial expression is the expression of various emotional states through the changes of facial muscles. Its biological significance is emphasized through the convergence of evidence from developmental, cross-cultural psychology and cognitive neuroscience. Infants develop an attentional preference for faces early on (Johnson et al., 1991) and can perceive and imitate different facial expressions (Meltzoff & Moore, 1977). This suggests that face perception plays an important role in human perception (Mckone, Crookes, & Kanwisher, 2009), which is believed to be responsible for the development of cognitive abilities in language and psychology (Meltzoff, 2003).

Different emotions produce different facial expressions. Because facial expressions can accurately and accurately reflect human emotions, they are the most important facial expressions for human beings to express emotions. Izzard divided people's faces into forehead-eyebrow, nose-root area and eye-nose-buccal area, believing that the activities of these three areas constituted different facial expressions and expressed corresponding emotions. For example, when a person is happy, the frontal eyebrow and nose root area relax, eyebrows drop; Eye, nose and buccal area eyes narrowing, cheek up, nasal expansion; The mouth of the lip and chin area is drawn back and upturned. The combination of muscle movements in these three areas makes up the facial expression of a smile. Different muscles play a dominant role in facial expressions that show different emotions. For example, the corners of the mouth turn up when laughing, the eyes and mouth open when surprised, and the eyebrows and corners of the mouth drop when sad.

A study by social psychologist Dacher Keltner found that humans have 27 types of emotional expression, including: Admiration, love, beauty, thank you, entertainment joke, anger, anxiety, fear, awkward, boring, tired of, calm quiet, confusion, longing desire, hatred, trance, heady excitement, fear, pain, trance, interested in fear, fear, joy, fun, homesickness nostalgia, release of comfort, sad sad, meet satisfaction, sexual desire, surprised

The expression of human emotions is often mixed and complex. Multiple emotions coexist in the same scene. It is not a pure emotion that exists in isolation and there is no clear boundary between different human emotions. In the same situation, people may trigger a variety of emotions. Therefore, the 27 expressions of human emotions that have been discovered do not exist in isolation, but can trigger multiple emotional responses in one situation.