Editing Face (section)

==Function==

===Emotional expression===
Faces are essential to expressing [[emotion]], consciously or unconsciously. A frown denotes disapproval; a smile usually means someone is pleased. Being able to read emotion in another's face is "the fundamental basis for empathy and the ability to interpret a person's reactions and predict the probability of ensuing behaviors". One study used the Multimodal Emotion Recognition Test<ref>[http://www.affective-sciences.org/MERT Multimodal Emotion Recognition Test (MERT) | Swiss Center for Affective Sciences] {{webarchive|url=https://web.archive.org/web/20110903094920/http://www.affective-sciences.org/MERT |date=2011-09-03 }}. Affective-sciences.org. Retrieved on 2011-04-29.</ref> to attempt to determine how to measure emotion. This research aimed at using a measuring device to accomplish what many people do every day: read emotion in a face.<ref>{{cite journal|author1=Bänziger, T.|author2=Grandjean, D.|author3=Scherer, K. R.|name-list-style=amp|year=2009|title=Emotion recognition from expressions in face, voice, and body: The Multimodal Emotion Recognition Test (MERT)|journal=Emotion|volume=9|issue=5|pages=691–704|doi=10.1037/a0017088|pmid=19803591|url=http://cms2.unige.ch/fapse/neuroemo/pdf/BaenzigerGrandjeanScherer-Emotion2009.pdf|citeseerx=10.1.1.455.8892|access-date=2017-11-01|archive-date=2017-08-08|archive-url=https://web.archive.org/web/20170808050957/http://cms2.unige.ch/fapse/neuroemo/pdf/BaenzigerGrandjeanScherer-Emotion2009.pdf|url-status=dead}}</ref>

The muscles of the face play a prominent role in the expression of emotion,<ref name="Moore" /> and vary among different individuals, giving rise to additional diversity in expression and facial features.<ref name="Braus 1921">{{cite book | title=Anatomie des Menschen: ein Lehrbuch für Studierende und Ärzte | author=Braus, Hermann | year=1921 | pages=777}}</ref>
[[Image:Braus 1921 379.png|right|thumb|250px|Variations of the [[risorius]], [[triangularis]] and [[Zygomaticus major muscle|zygomaticus]] muscles]]

People are also relatively good at determining if a smile is real or fake. A recent study looked at individuals judging forced and genuine smiles. While young and elderly participants equally could tell the difference for smiling young people, the "older adult participants outperformed young adult participants in distinguishing between posed and spontaneous smiles".<ref>{{cite journal|author1=Murphy, N. A. |author2=Lehrfeld, J. M. |author3= Isaacowitz, D. M. |name-list-style=amp |year=2010|title=Recognition of posed and spontaneous dynamic smiles in young and older adults|journal= Psychology and Aging|volume= 25|issue=4|pages=811–821|doi=10.1037/a0019888|pmid=20718538|pmc=3011054}}</ref> This suggests that with experience and age, we become more accurate at perceiving true emotions across various age groups.

===Perception and recognition===
{{main|Face perception}}
[[File:Martian face viking cropped.jpg|thumb|The [[face perception]] mechanisms of the brain, such as the [[fusiform face area]], can produce facial [[pareidolia]]s such as [[Cydonia (region of Mars)|this famous rock formation on Mars]].]]
[[Gestalt psychology|Gestalt psychologists]] theorize that a face is not merely a set of facial features, but is rather something meaningful in its form. This is consistent with the Gestalt theory that an image is seen in its entirety, not by its individual parts. According to Gary L. Allen, people adapted to respond more to faces during evolution as the natural result of being a social species. Allen suggests that the purpose of recognizing faces has its roots in the "parent-infant attraction, a quick and low-effort means by which parents and infants form an internal representation of each other, reducing the likelihood that the parent will abandon his or her offspring because of recognition failure".<ref>{{cite journal|author=Allen, Gary L. |title=Review: Seeking a Common Gestalt Approach to the Perception of Faces, Objects, and Scenes|journal= American Journal of Psychology |volume=119|issue=2|year=2006|pages=311–19|jstor=20445341|doi=10.2307/20445341|last2=Peterson|first2=Mary A.|last3=Rhodes|first3=Gillian}}</ref> Allen's work takes a psychological perspective that combines evolutionary theories with Gestalt psychology.

====Biological perspective====
Research has indicated that certain areas of the brain respond particularly well to faces. The [[fusiform face area]], within the [[fusiform gyrus]], is activated by faces, and it is activated differently for [[Shyness|shy]] and social people. A study confirmed that "when viewing images of strangers, shy adults exhibited significantly less activation in the fusiform gyri than did social adults".<ref>{{cite journal|author=Beaton, E. A., Schmidt, L. A., Schulkin, J., Antony, M. M., Swinson, R. P. & Hall, G. B.|year=2009|title=Different fusiform activity to stranger and personally familiar faces in shy and social adults|journal=Social Neuroscience|volume= 4|issue=4|pages=308–316|doi=10.1080/17470910902801021|pmid=19322727|s2cid=13304727}}</ref> Furthermore, particular areas respond more to a face that is considered attractive, as seen in another study: "Facial beauty evokes a widely distributed neural network involving perceptual, decision-making and reward circuits. In those experiments, the perceptual response across FFA and LOC remained present even when subjects were not attending explicitly to facial beauty".<ref>{{cite journal|author1=Chatterjee, A. |author2=Thomas, A. |author3=Smith, S. E. |author4= Aguirre, G. K. |name-list-style=amp |year=2009|title= The neural response to facial attractiveness|journal= Neuropsychology|volume= 23|issue=2|pages=135–143|doi=10.1037/a0014430|pmid=19254086|citeseerx=10.1.1.576.5894 }}</ref>