Editing Face perception (section)

===Ability to recognize familiar faces===
It is unclear when humans develop the ability to recognize familiar faces. Studies have varying results, and may depend on multiple factors (such as continued exposure to particular faces during a certain time period).
* Early perceptual experience is crucial to the development of adult visual perception, including the ability to identify familiar people and comprehend facial expressions. The capacity to discern between faces, like language{{how so|date=April 2021}}, appears to have broad potential in early life that is whittled down to the kinds of faces experienced in early life.<ref name="Charles A. Nelson 2001 3–18">{{Cite journal|author=Charles A. Nelson|author-link=Charles A. Nelson|date=March–June 2001|title=The development and neural bases of face recognition|journal=[[Infant and Child Development]]|volume=10|issue=1–2|pages=3–18|citeseerx=10.1.1.130.8912|doi=10.1002/icd.239}}</ref>
* The neural substrates of face perception in infants are similar to those of adults, but the limits of child-safe imaging technology currently obscure specific information from subcortical areas<ref name="Emi Nakato, Yumiko Otsuka, So Kanazawa, Masami K. Yamaguchi & Ryusuke Kakigi 2011 1600–1606">{{Cite journal|title = Distinct differences in the pattern of hemodynamic response to happy and angry facial expressions in infants--a near-infrared spectroscopic study|journal = [[NeuroImage]]|volume = 54|issue = 2|pages = 1600–6|date=January 2011|doi = 10.1016/j.neuroimage.2010.09.021|pmid = 20850548|last2 = Otsuka|last3 = Kanazawa|last4 = Yamaguchi|last5 = Kakigi|author1 = Emi Nakato|s2cid = 11147913|author-link1 = Emi Nakato}}</ref> like the [[amygdala]], which is active in adult facial perception. They also showed activity near the [[fusiform gyrus]],<ref name="Emi Nakato, Yumiko Otsuka, So Kanazawa, Masami K. Yamaguchi & Ryusuke Kakigi 2011 1600–1606"/>
* Healthy adults likely process faces via a retinotectal (subcortical) pathway.<ref>{{cite journal|author1=Awasthi B|author2=Friedman J|author3=Williams, MA|title=Processing of low spatial frequency faces at periphery in choice reaching tasks|journal=Neuropsychologia|volume = 49|issue = 7|pages = 2136–41|year = 2011|doi = 10.1016/j.neuropsychologia.2011.03.003|pmid=21397615|s2cid=7501604 }}</ref>
* Infants can discern between [[macaque]] faces at six months of age, but, without continued exposure, cannot do so at nine months of age. If they were shown photographs of macaques during this three-month period, they were more likely to retain this ability.<ref>{{Cite journal|title = Plasticity of face processing in infancy|journal = [[Proceedings of the National Academy of Sciences of the United States of America]]|volume = 102|issue = 14|pages = 5297–5300|date=April 2005|doi = 10.1073/pnas.0406627102|pmid = 15790676|pmc = 555965|last2 = Scott|last3 = Kelly|last4 = Shannon|last5 = Nicholson|last6 = Coleman|last7 = Nelson|author1 = O. Pascalis|author-link1 = O. Pascalis|bibcode = 2005PNAS..102.5297P |doi-access = free}}</ref>
* Faces "convey a wealth of information that we use to guide our social interactions".<ref name="Jeffery 2011 799–815">{{cite journal|last=Jeffery|first=L.|author2=Rhodes, G.|title=Insights into the development of face recognition mechanisms revealed by face aftereffects|journal=British Journal of Psychology|year= 2011|volume=102|issue=4|pages=799–815|doi=10.1111/j.2044-8295.2011.02066.x|pmid=21988385}}</ref> They also found that the neurological mechanisms responsible for face recognition are present by age five. Children process faces is similar to that of adults, but adults process faces more efficiently. The may be because of advancements in memory and cognitive functioning.<ref name="Jeffery 2011 799–815"/>
* Interest in the social world is increased by interaction with the physical environment. They found that training three-month-old infants to reach for objects with [[Velcro]]-covered "sticky mitts" increased the attention they pay to faces compared to moving objects through their hands and control groups.<ref name=Libertus11/>