Creation
Facial muscles
Facial expressions are vital to social communication between humans. They are caused by the movement of muscles that connect to the skin and fascia in the face. These muscles move the skin, creating lines and folds and causing the movement of facial features, such as the mouth and eyebrows. These muscles develop from the second pharyngeal arch in the embryo. The temporalis, masseter, and internal and external pterygoid muscles, which are mainly used for chewing, have a minor effect on expression as well. These muscles develop from the first pharyngeal arch.Neuronal pathways
There are two brain pathways associated with facial expression; the first is voluntary expression. Voluntary expression travels from the primary motor cortex through the pyramidal tract, specifically the corticobulbar projections. The cortex is associated with display rules in emotion, which are social precepts that influence and modify expressions. Cortically related expressions are made consciously. The second type of expression is emotional. These expressions originate from the extrapyramidal motor system, which involves subcortical nuclei. For this reason, genuine emotions are not associated with the cortex and are often displayed unconsciously. This is demonstrated in infants before the age of two; they display distress, disgust, interest, anger, contempt, surprise, and fear. Infants' displays of these emotions indicate that they are not cortically related. Similarly, blind children also display emotions, proving that they are subconscious rather than learned. Other subcortical facial expressions include the "knit brow" during concentration, raised eyebrows when listening attentively, and short "punctuation" expressions to add emphasis during speech. People can be unaware that they are producing these expressions.Asymmetries
The lower portions of the face are controlled by the oppositeNeural mechanisms in face perception
The amygdala plays an important role in facial recognition. Functional imaging studies have found that when shown pictures of faces, there is a large increase in the activity of the amygdala. The amygdala receives visual information from the thalamus via the subcortical pathways. The amygdala may also have a significant role in the recognition of fear and negative emotions. It is believed that the emotion disgust is recognized through activation of the insula and basal ganglia. The recognition of emotion may also utilize the occipitotemporal neocortex, orbitofrontal cortex and right frontoparietal cortices.Gender and facial cues
More than anything though, what shapes a child's cognitive ability to detect facial expression is being exposed to it from the time of birth. The more an infant is exposed to different faces and expressions, the more able they are to recognize these emotions and then mimic them for themselves. Infants are exposed to an array of emotional expressions from birth, and evidence indicates that they imitate some facial expressions and gestures (e.g., tongue protrusion) as early as the first few days of life. In addition, gender affects the tendency to express, perceive, remember, and forget specific emotions. For instance, angry male faces and happy female faces are more recognizable, compared to happy male faces and angry female faces.Communication
A 2020 study on "emotion residue" found that even when study participants attempted to make neutral facial expressions, their faces still retained emotion residue from prior expressions, and these prior expressions were able to be detected by observers. A 1988 study on the “facial feedback” hypothesis found that study participants mood was improved when they smiled. However, this study later failed a large replication attempt. One experiment investigated the influence of gaze direction and facial expression on face memory. Participants were shown a set of unfamiliar faces with either happy or angry facial expressions, which were either gazing straight ahead or had their gaze averted to one side. Memory for faces that were initially shown with angry expressions was found to be poorer when these faces had averted as opposed to direct gaze, whereas memory for individuals shown with happy faces was unaffected by gaze direction. It is suggested that memory for another individual's face partly depends on an evaluation of the behavioural intention of that individual. A 2025 study from Nottingham Trent University in England found that people who were facially expressive were more liked by social partners, which may be one reason why people produce, on average, 101 facial movements per minute during a given social interaction.Eye contact
A person's face, especially their eyes, creates the most obvious and immediate cues that lead to the formation of impressions. This article discusses eyes and facial expressions and the effect they have onSign languages
Facial expression is used inUniversality hypothesis
The universality hypothesis is the assumption that certain facial expressions and face-related acts or events are signals of specific emotions (happiness with laughter and smiling, sadness with tears, anger with a clenched jaw, fear with a grimace, or gurn, surprise with raised eyebrows and wide eyes along with a slight retraction of the ears, and disgust with a wrinkled nose and squinted eyes—emotions which frequently lack the social component of those like shame, pride, jealousy, envy, deference, etc.) and are recognized by people regardless of culture, language, or time. The belief in the evolutionary basis of these kinds of facial expressions can be traced back to Darwin's '' The Expression of the Emotions in Man and Animals.'' Reviews of the universality hypothesis have been both supportive and critical. Work in 2013 by Nelson and Russell and Jack et al. has been especially critical.Support
Ekman's work on facial expressions had its starting point in the work of psychologist Silvan Tomkins. Ekman showed that facial expressions of emotion are not culturally determined, but universal across human cultures. To demonstrate his universality hypothesis, Ekman ran a test on a group of the South Fore people ofCriticism
Both sides of this debate agree that the face expresses emotion. The controversy surrounds the uncertainty about what specific emotional information is read from a facial expression. Opponents of the universality hypothesis believe that more general information is pieced together with other contextual information in order to determine how a person feels. One argument against the evidence presented in support of the universality hypothesis is that the method typically used to demonstrate universality inflates recognition scores. Although each factor may contribute only a small amount to the inflation, combined, they can produce exaggerated scores. The three main factors are the following: * The universality hypothesis focuses on people's abilities to recognize spontaneous facial expressions as they occur naturally. However, the facial expressions used to test this hypothesis are posed. Studies of spontaneous facial expressions are rare and find that participants' recognition of the expressions is lower than that of the corresponding posed expressions. * In most studies, participants are shown more than one facial expression (Ekman recommends six of each expression). However, people judge facial expressions relative to others that they have seen, and participants who judge more than one facial expression have higher recognition rates than those who judge only one. * The response format that is most commonly used in emotion recognition studies is forced choice. In forced choice, for each facial expression, participants are asked to select their response from a short list of emotion labels. The forced choice method determines the emotion attributed to the facial expressions via the labels that are presented. That is, participants will select the best match to the facial expression even if it is not the emotion label they would have provided spontaneously and even if they would not have labeled the expression as an emotion at all.Evolutionary significance of universality
Darwin argued that the expression of emotions has evolved in humans from animal ancestors, who would have used similar methods of expression. Darwin believed that expressions were unlearned and innate in human nature and were therefore evolutionarily significant for survival. He compiled supporting evidence from his research on different cultures, on infants, and in other animal species. Ekman found that people from different cultures recognized certain facial expressions despite vast cultural differences, and his findings tended to confirm Darwin's initial hypothesis. Cross-cultural studies had shown that there are similarities in the way emotions are expressed across diverse cultures, but studies have even shown that there are similarities between species in how emotions are expressed. Research has shown that chimpanzees are able to communicate many of the same facial expressions as humans through the complex movements of the facial muscles. In fact, the facial cues were so similar that Ekman's Facial Action Coding System could be applied to the chimps in evaluating their expressions. Of course, differences between the species' physical facial properties, such as white sclera and everted lips in chimps, would mean that some expressions could not be compared. Similarly, Darwin observed that infants' method of expression for certain emotions was instinctive, as they were able to display emotional expressions they had not themselves yet witnessed. Facial morphology impacts expression recognition in important ways, and therefore, infant facial morphology may also serve some specific communicative function. These similarities in morphology and movement are important for the correct interpretation of an emotion. Darwin was particularly interested in the functions of facial expression as evolutionarily important for survival. He looked at the functions of facial expression in terms of the utility of expression in the life of the animal and in terms of specific expressions within species. Darwin deduced that some animals communicated feelings of different emotional states with specific facial expressions. He further concluded that this communication was important for the survival of animals in group-dwelling species; the skill to effectively communicate or interpret another animal's feelings and behaviors would be a principal trait in naturally fit species. However, this suggests that solitary species such as orangutans would not exhibit such expressions. For a discussion of the controversies on these claims, see Fridlund and Russell & Fernandez Dols.See also
* Affect display * Bell's palsy *References
*External links