Editing Face

{{short description|Part of the body that is at the front of the head}}
{{other uses}}
{{Redirect|Faces}}
{{redirect|Human face|the miniseries|The Human Face{{!}}''The Human Face''}}
{{human-centric|date=March 2024}}
{{Infobox anatomy
| Name        = Face
| Latin       = facies, facia or fave
| Image       = File:Human faces.jpg
| Caption     = Face of a woman (left) and face of a man (right)
| Width       = 
| Image2      = Sobo 1909 260.png
| Caption2    = Ventrolateral aspect of the human face with skin removed, showing muscles of the face
| Precursor   = 
| System      = 
| Artery      = 
| Vein        = 
| Nerve       = 
| Lymph       = 
}}
The '''face''' is the front of the head that features the [[eyes]], [[nose]] and [[mouth]], and through which animals express many of their [[emotion]]s.<ref name="Moore">{{cite book | title=Moore's clinical anatomy | publisher=Lippincott Williams & Wilkins |author1=Moore, Keith L. |author2=Dalley, Arthur F. |author3=Agur, Anne M. R. | year=2010 | location=United States of America | pages=843–980 | isbn=978-1-60547-652-0}}</ref><ref name="Scotland Governement Year of Discovery 2011">{{cite web | url=http://www.scotland.gov.uk/News/Releases/2011/12/22105642 | title=Year of Discovery, Faceless and Brainless Fish | date=2011-12-29 | access-date=December 11, 2013 | archive-date=2014-10-06 | archive-url=https://web.archive.org/web/20141006085750/http://www.scotland.gov.uk/News/Releases/2011/12/22105642 | url-status=dead }}</ref> The face is crucial for human [[Personal identity|identity]], and damage such as scarring or developmental deformities may affect the psyche adversely.<ref name="Moore" />

==Structure==
The front of the [[human head]] is called the face. It includes several distinct areas,<ref>[http://dictionary.reference.com/browse/face Face | Define Face at Dictionary.com]. Dictionary.reference.com. Retrieved on 2011-04-29.</ref> of which the main features are:
*The [[forehead]], comprising the [[human skin|skin]] beneath the [[hair]]line, bordered laterally by the [[temple (anatomy)|temple]]s and inferiorly by [[eyebrow]]s and [[ear]]s
*The [[Human eye|eye]]s, sitting in the [[orbit (anatomy)|orbit]] and protected by [[eyelid]]s and [[eyelash]]es
* The distinctive [[human nose]] [[Ethmoid bone|shape]], [[nostril]]s, and [[nasal septum]]
*The [[cheek]]s, covering the [[maxilla]] and [[mandible]] (or jaw), the extremity of which is the [[chin]]
*The [[Human mouth|mouth]], with the upper [[lip]] divided by the [[philtrum]], sometimes revealing the [[Human tooth|teeth]]

Facial [[biometrics|appearance]] is vital for human [[Identity (philosophy)|recognition]] and [[communication]]. [[Facial muscles]] in humans allow [[facial expression|expression]] of [[emotion]]s.<ref>{{Cite journal |last=Wolf |first=Karsten |date=2015-12-31 |title=Measuring facial expression of emotion |url=https://www.tandfonline.com/doi/full/10.31887/DCNS.2015.17.4/kwolf |journal=Dialogues in Clinical Neuroscience |language=en |volume=17 |issue=4 |pages=457–462 |doi=10.31887/DCNS.2015.17.4/kwolf |issn=1958-5969 |pmc=4734883 |pmid=26869846}}</ref>

The face is itself a highly [[sense|sensitive]] region of the human body and its expression may change when the [[Human brain|brain]] is stimulated by any of the many human [[sense]]s, such as [[Somatosensory system|touch]], [[temperature]], [[olfaction|smell]], [[taste]], [[hearing (sense)|hearing]], [[Vestibular sense|movement]], [[hunger]], or [[visual perception|visual stimuli]].<ref>[http://www.face-and-emotion.com/dataface/anatomy/anatomy.jsp Anatomy of the Face and Head Underlying Facial Expression] {{webarchive|url=https://web.archive.org/web/20071129195258/http://www.face-and-emotion.com/dataface/anatomy/anatomy.jsp |date=2007-11-29 }}. Face-and-emotion.com. Retrieved on 2011-04-29.</ref>

===Variability===
{{See also|Human variability}}

The face is the feature which best distinguishes a [[person]]. Specialized regions of the [[human brain]], such as the [[fusiform face area]] (FFA), enable facial recognition; when these are [[prosopagnosia|damaged]], it may be impossible to recognize faces even of intimate family members. The pattern of specific organs, such as the eyes, or of parts of them, is used in [[biometric identification]] to uniquely identify individuals.

====Shape====
{{multiple image
| align = right
| direction = horizontal
| image2 = Braus 1921 375.png
| caption2 = The muscles of the face are important when engaging in facial expressions.
| width2 = 150
| image3 = Blausen 0393 FacialBones 01.png
| caption3 = [[Human skeleton|Skeletal anatomy]] of the face
| width3 = 150
|}}
The shape of the face is influenced by the [[bone|bone-structure]] of the [[Skull#Humans|skull]], and each face is unique through the [[anatomical variation]] present in the bones of the [[facial skeleton|viscerocranium]] (and [[neurocranium]]).<ref name="Moore" /> The bones involved in shaping the face are mainly the [[maxilla]], [[mandible]], [[nasal bone]], [[zygomatic bone]], and [[frontal bone]]. Also important are various [[soft tissue]]s, such as [[adipose tissue|fat]], [[hair]] and [[Human skin|skin]] (of which color may vary).<ref name="Moore" />

The face changes over time, and features common in [[children]] or [[infant|babies]], such as prominent [[buccal fat pad|buccal fat-pads]] disappear over time, their role in the infant being to stabilize the cheeks during [[suckling]].
While the buccal fat-pads often diminish in size, the prominence of bones increase with age as they grow and develop.<ref name="Moore" />

Facial shape – such as [[facial symmetry]] – is an important determinant of [[human beauty|beauty]].

====Other characteristics====
Visible variable features of the face other than shapes and proportions include color (paleness, [[sun tan]] and [[skin color|genetic default pigmentation]]), hair (length, [[Human hair color|color]], [[hair loss|loss]], [[hair graying|graying]]), [[wrinkle]]s,<ref name="10.1371/journal.pone.0008021"/><ref name="10.1111/ics.12128"/> facial hair (e.g. [[beard]]s), skin sagging,<ref name="10.1111/ics.12128"/> discolorations<ref name="10.1186/s13104-019-4404-z"/> ([[Hyperpigmentation|dark spots]],<ref name="10.1111/ics.12128"/> [[freckle]]s and [[Periorbital dark circles|eye circles]]<ref name="10.1111/ics.12128"/>), [[Sweat gland|pore]]-variabilities,<ref name="10.1117/12.975404"/> skin blemishes ([[pimple]]s, [[scar]]s, [[burn|burn marks]]). Many of these features can also vary over time due to [[aging]],<ref name="10.1111/ics.12128">{{cite journal |last1=Porcheron |first1=A. |last2=Latreille |first2=J. |last3=Jdid |first3=R. |last4=Tschachler |first4=E. |last5=Morizot |first5=F. |title=Influence of skin ageing features on Chinese women's perception of facial age and attractiveness |journal=International Journal of Cosmetic Science |date=August 2014 |volume=36 |issue=4 |pages=312–320 |doi=10.1111/ics.12128 |pmid=24712710 |pmc=4283052 |s2cid=1546162 |language=en |issn=0142-5463}}</ref><ref name="10.1371/journal.pone.0008021"/><ref name="10.1186/s13104-019-4404-z">{{cite journal |last1=Buranasirin |first1=Punnapath |last2=Pongpirul |first2=Krit |last3=Meephansan |first3=Jitlada |title=Development of a Global Subjective Skin Aging Assessment score from the perspective of dermatologists |journal=BMC Research Notes |date=28 June 2019 |volume=12 |issue=1 |pages=364 |doi=10.1186/s13104-019-4404-z |pmid=31253172 |pmc=6599371 |language=en |issn=1756-0500 |doi-access=free }}</ref> [[skin care]], nutrition,<ref>{{cite journal |last1=Cao |first1=Changwei |last2=Xiao |first2=Zhichao |last3=Wu |first3=Yinglong |last4=Ge |first4=Changrong |title=Diet and Skin Aging—From the Perspective of Food Nutrition |journal=Nutrients |date=March 2020 |volume=12 |issue=3 |pages=870 |doi=10.3390/nu12030870 |pmid=32213934 |pmc=7146365 |language=en |issn=2072-6643|doi-access=free }}</ref><ref>{{cite journal |last1=Mekić |first1=Selma |last2=Jacobs |first2=Leonie C. |last3=Hamer |first3=Merel A. |last4=Ikram |first4=M. Arfan |last5=Schoufour |first5=Josje D. |last6=Gunn |first6=David A. |last7=Kiefte-de Jong |first7=Jessica C. |last8=Nijsten |first8=Tamar |title=A healthy diet in women is associated with less facial wrinkles in a large Dutch population-based cohort |journal=Journal of the American Academy of Dermatology |date=1 May 2019 |volume=80 |issue=5 |pages=1358–1363.e2 |doi=10.1016/j.jaad.2018.03.033 |pmid=29601935 |s2cid=4487261 |language=en |issn=0190-9622}}</ref><ref name="10.1111/jdv.16614">{{cite journal |last1=Passeron |first1=T. |last2=Krutmann |first2=J. |last3=Andersen |first3=M.L. |last4=Katta |first4=R. |last5=Zouboulis |first5=C.C. |title=Clinical and biological impact of the exposome on the skin |journal=Journal of the European Academy of Dermatology and Venereology |date=July 2020 |volume=34 |issue=S4 |pages=4–25 |doi=10.1111/jdv.16614 |pmid=32677068 |s2cid=220609978 |language=en |issn=0926-9959|doi-access=free }}</ref><ref name="10.1016/j.clindermatol.2019.04.002"/><ref name="10.3892/etm.2019.8342">{{cite journal |last1=Lupu |first1=Mihaela-Adi |last2=Gradisteanu Pircalabioru |first2=Gratiela |last3=Chifiriuc |first3=Mariana-Carmen |last4=Albulescu |first4=Radu |last5=Tanase |first5=Cristiana |title=Beneficial effects of food supplements based on hydrolyzed collagen for skin care (Review) |journal=Experimental and Therapeutic Medicine |date=1 July 2020 |volume=20 |issue=1 |pages=12–17 |doi=10.3892/etm.2019.8342 |pmid=32508986 |pmc=7271718 |s2cid=213518696 |issn=1792-0981}}</ref><ref>{{cite journal |last1=Marcílio Cândido |first1=Thalita |last2=Bueno Ariede |first2=Maíra |last3=Vieira Lima |first3=Fabiana |last4=de Souza Guedes |first4=Luciana |last5=Robles Velasco |first5=Maria Valéria |last6=Rolim Baby |first6=André |last7=Rosado |first7=Catarina |title=Dietary Supplements and the Skin: Focus on Photoprotection and Antioxidant Activity—A Review |journal=Nutrients |date=16 March 2022 |volume=14 |issue=6 |pages=1248 |doi=10.3390/nu14061248 |pmid=35334905 |pmc=8953599 |language=en |issn=2072-6643|doi-access=free }}</ref> the [[exposome]]<ref name="10.1016/j.jdermsci.2016.09.015">{{cite journal |last1=Krutmann |first1=Jean |last2=Bouloc |first2=Anne |last3=Sore |first3=Gabrielle |last4=Bernard |first4=Bruno A. |last5=Passeron |first5=Thierry |title=The skin aging exposome |journal=Journal of Dermatological Science |date=1 March 2017 |volume=85 |issue=3 |pages=152–161 |doi=10.1016/j.jdermsci.2016.09.015 |pmid=27720464 |language=en |issn=0923-1811|doi-access=free }}</ref> (such as harmful substances of the general environment,<ref name="10.1111/jdv.16614"/><ref name="10.1016/j.jdermsci.2016.09.015"/> workplace and cosmetics), psychological factors,<ref name="10.1111/jdv.16614"/> and behavior (such as smoking,<ref name="10.1016/j.jdermsci.2016.09.015"/> sleep,<ref name="10.1111/jdv.16614"/> physical activity and [[Health effects of sunlight exposure|sun damage]]<ref name="10.1371/journal.pone.0008021"/><ref name="10.1186/s13104-019-4404-z"/><ref name="10.1111/jdv.16614"/>).

Mechanisms underlying these include changes related to [[peptide]]s (notably [[collagen]]),<ref name="10.1186/s13104-019-4404-z"/><ref name="10.1111/jdv.16614"/> [[inflammation]],<ref name="10.1111/jdv.16614"/><ref name="10.3892/etm.2019.8342"/> production of various proteins (notably [[elastin]] and other [[extracellular matrix protein|ECM proteins]]),<ref name="10.3892/etm.2019.8342"/> the structure of [[subcutaneous tissue]],<ref name="10.1371/journal.pone.0008021">{{cite journal |last1=Gunn |first1=David A. |last2=Rexbye |first2=Helle |last3=Griffiths |first3=Christopher E. M. |last4=Murray |first4=Peter G. |last5=Fereday |first5=Amelia |last6=Catt |first6=Sharon D. |last7=Tomlin |first7=Cyrena C. |last8=Strongitharm |first8=Barbara H. |last9=Perrett |first9=Dave I. |last10=Catt |first10=Michael |last11=Mayes |first11=Andrew E. |last12=Messenger |first12=Andrew G. |last13=Green |first13=Martin R. |last14=Ouderaa |first14=Frans van der |last15=Vaupel |first15=James W. |last16=Christensen |first16=Kaare |title=Why Some Women Look Young for Their Age |journal=PLOS ONE |date=1 December 2009 |volume=4 |issue=12 |pages=e8021 |doi=10.1371/journal.pone.0008021 |pmid=19956599 |pmc=2779449 |bibcode=2009PLoSO...4.8021G |language=en |issn=1932-6203|doi-access=free }}</ref><ref name="10.1186/s13104-019-4404-z"/> [[hormone]]s,<ref name="10.1111/jdv.16614"/> fibers (such as elastic fibers or elasticity)<ref name="10.1186/s13104-019-4404-z"/> and the [[skin barrier]].<ref name="10.1016/j.jdermsci.2016.09.015"/>

The desire of many to look young for their age and/or attractive<ref name="10.1111/ics.12128"/> has led to the establishment of a large [[cosmetics industry]],<ref name="10.1371/journal.pone.0008021"/> which is largely concerned with [[make-up]] that is applied on top of the skin (topically) to temporarily change appearance but it or [[dermatology]] also develop [[anti-aging product]]s (and related products and procedures) that in some cases affect underlying biology and are partly applied preventively.<ref name="10.1016/j.clindermatol.2019.04.002"/> Facial traits are also used in [[biometric]]s<ref>{{cite journal |last1=Reid |first1=D.A. |last2=Samangooei |first2=S. |last3=Chen |first3=C. |last4=Nixon |first4=M.S. |last5=Ross |first5=A. |title=Soft Biometrics for Surveillance: An Overview |journal=Handbook of Statistics |date=2013 |volume=31 |pages=327–352 |doi=10.1016/b978-0-444-53859-8.00013-8 |publisher=Elsevier |isbn=9780444538598 |url=https://eprints.soton.ac.uk/342219/1/Chapter%252013%2520hb%2520statistics.pdf |language=en}}</ref><ref>{{cite book |last1=Arbab-Zavar |first1=Banafshe |last2=Wei |first2=Xingjie |last3=Bustard |first3=John D. |last4=Nixon |first4=Mark S. |last5=Li |first5=Chang-Tsun |chapter=On Forensic Use of Biometrics |title=Handbook of Digital Forensics of Multimedia Data and Devices |date=18 December 2015 |pages=270–304 |doi=10.1002/9781118705773.ch7 |publisher=John Wiley & Sons, Ltd |isbn=9781118705773 |language=en}}</ref> and there have been attempts at reproducible quantifications.<ref name="10.1186/s13104-019-4404-z"/><ref name="10.1117/12.975404">{{cite journal |last1=Gartstein |first1=Vladimir |last2=Shaya |first2=Steven A. |editor-first1=Samuel J |editor-first2=Roger H |editor-last1=Dwyer Iii |editor-last2=Schneider |title=Image Analysis Of Facial Skin Features |journal=Society of Photo-Optical Instrumentation Engineers (Spie) Conference Series |series=Application of Optical Instrumentation in Medicine XIV and Picture Archiving and Communication Systems |date=12 June 1986 |volume=0626 |pages=284 |doi=10.1117/12.975404|bibcode=1986SPIE..626..284G |s2cid=129634133 }}</ref> [[Human skin|Skin]] health is considered a major factor in human [[well-being]] and the perception of health in humans.<ref name="10.1016/j.clindermatol.2019.04.002">{{cite journal |last1=Zouboulis |first1=Christos C. |last2=Ganceviciene |first2=Ruta |last3=Liakou |first3=Aikaterini I. |last4=Theodoridis |first4=Athanasios |last5=Elewa |first5=Rana |last6=Makrantonaki |first6=Eugenia |title=Aesthetic aspects of skin aging, prevention, and local treatment |journal=Clinics in Dermatology |date=1 July 2019 |volume=37 |issue=4 |pages=365–372 |doi=10.1016/j.clindermatol.2019.04.002 |pmid=31345325 |s2cid=149692214 |language=en |issn=0738-081X}}</ref>

====Genetics====
[[Human genetics|Genes]] are a major factor in the particular appearance of a person's face with the high similarity of faces of [[:simple:Identical twins#Twin research|identical twins]] indicating that most of facial variability is determined genetically.<ref>{{cite journal |last1=Crouch |first1=Daniel J. M. |last2=Winney |first2=Bruce |last3=Koppen |first3=Willem P. |last4=Christmas |first4=William J. |last5=Hutnik |first5=Katarzyna |last6=Day |first6=Tammy |last7=Meena |first7=Devendra |last8=Boumertit |first8=Abdelhamid |last9=Hysi |first9=Pirro |last10=Nessa |first10=Ayrun |last11=Spector |first11=Tim D. |last12=Kittler |first12=Josef |last13=Bodmer |first13=Walter F. |title=Genetics of the human face: Identification of large-effect single gene variants |journal=Proceedings of the National Academy of Sciences |date=23 January 2018 |volume=115 |issue=4 |pages=E676–E685 |doi=10.1073/pnas.1708207114 |pmid=29301965 |pmc=5789906 |bibcode=2018PNAS..115E.676C |language=en |issn=0027-8424|doi-access=free }}</ref>

Studies have identified genes and gene regions determining face shape and differences in various facial features. A 2021 study found that a version of a gene associated with lip thickness – possibly selected for due to adaption to cold climate via fat distribution – [[Interbreeding between archaic and modern humans|introgressed]] from ancient humans – [[Denisovan]]s – into the modern humans [[Genetic history of indigenous peoples of the Americas|Native Americans]].<ref>{{cite news |title=Genes for face shape identified |url=https://phys.org/news/2021-02-genes.html |access-date=6 March 2021 |work=phys.org |language=en}}</ref><ref>{{cite news |title=Genes for face shape identified {{!}} Scienmag: Latest Science and Health News |url=https://scienmag.com/genes-for-face-shape-identified/ |access-date=6 March 2021 |work=ScienceMag |archive-date=16 January 2022 |archive-url=https://web.archive.org/web/20220116035239/https://scienmag.com/genes-for-face-shape-identified/ |url-status=dead }}</ref><ref>{{cite journal |last1=Bonfante |first1=Betty |last2=Faux |first2=Pierre |last3=Navarro |first3=Nicolas |last4=Mendoza-Revilla |first4=Javier |last5=Dubied |first5=Morgane |last6=Montillot |first6=Charlotte |last7=Wentworth |first7=Emma |last8=Poloni |first8=Lauriane |last9=Varón-González |first9=Ceferino |last10=Jones |first10=Philip |last11=Xiong |first11=Ziyi |last12=Fuentes-Guajardo |first12=Macarena |last13=Palmal |first13=Sagnik |last14=Chacón-Duque |first14=Juan Camilo |last15=Hurtado |first15=Malena |last16=Villegas |first16=Valeria |last17=Granja |first17=Vanessa |last18=Jaramillo |first18=Claudia |last19=Arias |first19=William |last20=Barquera |first20=Rodrigo |last21=Everardo-Martínez |first21=Paola |last22=Sánchez-Quinto |first22=Mirsha |last23=Gómez-Valdés |first23=Jorge |last24=Villamil-Ramírez |first24=Hugo |last25=Cerqueira |first25=Caio C. Silva de |last26=Hünemeier |first26=Tábita |last27=Ramallo |first27=Virginia |last28=Liu |first28=Fan |last29=Weinberg |first29=Seth M. |last30=Shaffer |first30=John R. |last31=Stergiakouli |first31=Evie |last32=Howe |first32=Laurence J. |last33=Hysi |first33=Pirro G. |last34=Spector |first34=Timothy D. |last35=Gonzalez-José |first35=Rolando |last36=Schüler-Faccini |first36=Lavinia |last37=Bortolini |first37=Maria-Cátira |last38=Acuña-Alonzo |first38=Victor |last39=Canizales-Quinteros |first39=Samuel |last40=Gallo |first40=Carla |last41=Poletti |first41=Giovanni |last42=Bedoya |first42=Gabriel |last43=Rothhammer |first43=Francisco |last44=Thauvin-Robinet |first44=Christel |last45=Faivre |first45=Laurence |last46=Costedoat |first46=Caroline |last47=Balding |first47=David |last48=Cox |first48=Timothy |last49=Kayser |first49=Manfred |last50=Duplomb |first50=Laurence |last51=Yalcin |first51=Binnaz |last52=Cotney |first52=Justin |last53=Adhikari |first53=Kaustubh |last54=Ruiz-Linares |first54=Andrés |title=A GWAS in Latin Americans identifies novel face shape loci, implicating VPS13B and a Denisovan introgressed region in facial variation |journal=Science Advances |date=1 February 2021 |volume=7 |issue=6 |pages=eabc6160 |doi=10.1126/sciadv.abc6160 |pmid=33547071 |pmc=7864580 |bibcode=2021SciA....7.6160B |language=en |issn=2375-2548|doi-access=free }}</ref> Another study found look-alike humans ([[doppelgänger]]s) have genetic similarities, sharing genes affecting not only the face but also some [[phenotype]]s of physique and [[Behavioral genetics|behavior]].<ref>{{cite news |last1=Golembiewski |first1=Kate |last2=Brunelle |first2=François |title=Your Doppelgänger Is Out There and You Probably Share DNA With Them |url=https://www.nytimes.com/2022/08/23/science/doppelgangers-twins-dna.html |access-date=15 September 2022 |work=The New York Times |date=23 August 2022}}</ref><ref>{{cite journal |last1=Joshi |first1=Ricky S. |last2=Rigau |first2=Maria |last3=García-Prieto |first3=Carlos A. |last4=Moura |first4=Manuel Castro de |last5=Piñeyro |first5=David |last6=Moran |first6=Sebastian |last7=Davalos |first7=Veronica |last8=Carrión |first8=Pablo |last9=Ferrando-Bernal |first9=Manuel |last10=Olalde |first10=Iñigo |last11=Lalueza-Fox |first11=Carles |last12=Navarro |first12=Arcadi |last13=Fernández-Tena |first13=Carles |last14=Aspandi |first14=Decky |last15=Sukno |first15=Federico M. |last16=Binefa |first16=Xavier |last17=Valencia |first17=Alfonso |last18=Esteller |first18=Manel |title=Look-alike humans identified by facial recognition algorithms show genetic similarities |journal=Cell Reports |date=23 August 2022 |volume=40 |issue=8 |page=111257 |doi=10.1016/j.celrep.2022.111257 |pmid=36001980 |language=English |issn=2211-1247|doi-access=free|hdl=10230/54047 |hdl-access=free }}</ref> A study identified genes controlling the shape of the nose and chin.<ref>{{cite journal |last1=Adhikari |first1=Kaustubh |last2=Fuentes-Guajardo |first2=Macarena |display-authors=et al. |title=A genome-wide association scan implicates DCHS2, RUNX2, GLI3, PAX1 and EDAR in human facial variation |journal=Nature Communications |date=19 May 2016 |volume=7 |issue=1 |pages=11616 |doi=10.1038/ncomms11616|pmid=27193062 |pmc=4874031 |bibcode=2016NatCo...711616A |s2cid=11364821 }}
* University press release: {{cite news |title=Genes for nose shape found |url=https://www.sciencedaily.com/releases/2016/05/160519081832.htm |access-date=6 November 2022 |work=[[University College London]] via ScienceDaily |language=en}}</ref> [[List of biological databases|Biological databases]] may be used to aggregate and discover associations between facial [[phenotype]]s and genes.<ref>{{cite journal |last1=Hassani-Pak |first1=Keywan |last2=Rawlings |first2=Christopher |title=Knowledge Discovery in Biological Databases for Revealing Candidate Genes Linked to Complex Phenotypes |journal=Journal of Integrative Bioinformatics |date=1 March 2017 |volume=14 |issue=1 |doi=10.1515/jib-2016-0002 |pmid=28609292 |pmc=6042805 |language=en |issn=1613-4516|doi-access=free }}</ref><ref>{{cite journal |title=Defining a Face: What Can DNA Phenotyping Really Tell Us About An Unknown Sample? |journal=National Institute of Justice |url=https://nij.ojp.gov/topics/articles/defining-face-what-can-dna-phenotyping-really-tell-us-about-unknown-sample |access-date=4 April 2021 |language=en |quote=Based on Walsh’s phenotype analysis, King determined that one of the earliest paintings of Richard III, the 1510 “Arched Framed Portrait,” best matched the genetic information. “We were still dealing with categories [of color] because we’re not at the quantitative level yet,” Walsh said of her determination of Richard III’s hair and eye color. “[King] wanted something physical to see, and that’s what spurred me to move toward the quantitative so strongly. Because I could always say to someone, ‘blue’ or ‘blonde,’ and they would say, ‘I need to see this physically.’ So that is what I’m working on now. I want to produce that result.” Walsh has gathered DNA phenotype data from 2,000 Irish, Greek and U.S. individuals and is currently collecting data from 3,000 additional individuals from those same countries in order to create a phenotype-genotype database and prediction model. For forensic purposes, she would like to be able to start with a “blank person” and with a sample of DNA, determine the actual eye, hair and skin pigmentation.}}</ref>

{{multiple image
| align = center
| direction = horizontal
| image1 = Anthropogenie; oder, Entwickelungs-geschichte des Menschen (1910) (19181312270).jpg
| caption1 = Human face development, by [[Haeckel]]
| width1 = 132
| image2 = Kulusuk, Inuit man (6822268117).jpg
| caption2 = A man's face
| width2 = 134
| image3 = Tigray Woman (8756820602).jpg
| caption3 = A woman's face
| width3 = 133
| image4 = HV Head Shot copy.jpg
| caption4 = An intersex person's face
| width4 = 170
|}}

==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>

==Society and culture==

===Cosmetic surgery===
[[Cosmetic surgery]] can be used to alter the appearance of the facial features.<ref>[https://www.nlm.nih.gov/medlineplus/plasticandcosmeticsurgery.html Plastic and Cosmetic Surgery: MedlinePlus]. Nlm.nih.gov. Retrieved on 2011-04-29.</ref> Maxillofacial surgery may also be used in cases of [[facial trauma]], injury to the face and skin diseases. Severely disfigured individuals have recently received full [[face transplant]]s and partial transplants of skin and muscle tissue.<ref>[http://www.brighamandwomens.org/Departments_and_Services/surgery/services/PlasticSurg/Reconstructive/FaceTransplantSurgery/default.aspx Face Transplant Surgery at Brigham and Women's Hospital]</ref>

===Caricatures===
[[Caricature]]s often exaggerate facial features to make a face more easily recognized in association with a pronounced portion of the face of the individual in question—for example, a caricature of [[Osama bin Laden]] might focus on his facial hair and nose; a caricature of [[George W. Bush]] might enlarge his ears to the size of an elephant's; a caricature of [[Jay Leno]] may pronounce his head and chin; and a caricature of [[Mick Jagger]] might enlarge his lips. Exaggeration of memorable features helps people to recognize others when presented in a caricature form.<ref>[http://www.edu.dudley.gov.uk/art/specproj/caricatures/menu.htm information about caricatures] {{webarchive|url=https://web.archive.org/web/20070826140342/http://www.edu.dudley.gov.uk/art/specproj/caricatures/menu.htm |date=2007-08-26 }}. Edu.dudley.gov.uk. Retrieved on 2011-04-29.</ref>

===Metaphor===
By extension, anything which is the forward or world-facing part of a system which has internal structure is considered its "face", like the [[façade]] of a building. For example, a [[Public Relations Officer|public relations]] or [[press officer]] might be called the "face" of the organization he or she represents. "Face" is also used metaphorically in a [[Face (sociological concept)|sociological context]] to refer to reputation or standing in society, particularly Chinese society,<ref>{{cite journal|author=Ho, David Yau-fai |title=On the Concept of Face|journal=American Journal of Sociology |volume=81 |issue=4 |date=January 1976 |pages=867&ndash;84|doi=10.1086/226145|jstor=2777600|s2cid=145513767}}: "The concept of face is, of course, Chinese in origin".</ref> and is spoken of as a resource which can be won or lost. Because of the association with individuality, the anonymous person is sometimes referred to as "faceless".

==See also==
{{div col}}
* [[Diprosopus]]
* [[Face perception]]
* [[Facial symmetry]]
* [[Physiognomy]]
* [[Portrait]]
* [[Prosopagnosia]]
{{div col end}}
{{wikiquote|Faces}}
{{commons|face}}

==References==
{{Reflist|30em}}

{{Human regional anatomy|state=collapsed}}

{{Authority control}}

[[Category:Face| ]]