Thursday, October 22, 2009

Face and gender recognition

It is told that an elder came to Scete with his son who was not yet weaned. The boy was raised in the monastery and did not know there were women. When he became a man, the demons represented images of women to him. He was astonished and informed his father. Now one day the two of them went to Egypt and, seeing some women, the young man told his father, “Father, those are the ones who would come and see me at Scete during the night!”

Sayings of the Fathers (Apophthegmata Patrum) 5th century (Regnault, 1966, p.73)

We seem to be born with the ability to recognize the human face. Even infants as young as 1 month old show a consistent, spontaneous preference for face-like stimuli over nonface-like patterns. Such recognition seems guided by an inborn representation of the main facial features, particularly the eyes and the mouth (Pascalis & Kelly, 2008). Brain-damaged subjects provide further evidence of a mental module that specifically processes facial images:

Associative visual agnosia does not always seem to affect the recognition of all types of stimuli equally. The selectivity in some cases of agnosia lends support to the view that there are specialized systems for recognizing particular types of stimuli. The best known example of this is prosopagnosia, the inability to recognize faces after brain damage. Prosopagnosics cannot recognize familiar people by their faces alone, and must rely on other cues for recognition such as a person’s voice, or distinctive clothing or hairstyles. The disorder can be so severe that even close friends and family members will not be recognized. Although many prosopagnosics have some degree of difficulty recognizing objects other than faces, in some cases the deficit appears strikingly selective for faces. (Farah, 1996)

If this mental representation is inborn, does it come in two forms, one for a female face and another for a male face? Or is it gender-neutral? By studying visual adaptation to facial images, Little et al. (2005) concluded that different neural populations process male and female faces. This difference seems to exist at the level of higher-level neurons that code for the entire face, rather than for specific characteristics (Bestelmeyer et al., 2008). These findings were partially replicated by Jaquet (2007), who found evidence for both common and sex-selective neurons.

Ramsey-Rennels and Langlois (2006) reviewed the literature on male and female face recognition by infants:

First, 3- to 4-month-olds have more difficulty discriminating among male faces and subsequently recognizing them than they do female faces (Quinn et al., 2002). Second, older infants are more skilled at categorizing female faces than they are at categorizing male faces: Whereas 10-month-olds easily recognize that a sex-ambiguous female face does not belong with a group of sex-typical female faces, they have more difficulty excluding a sex-ambiguous male face from a group of sex-typical male faces (data interpretation of Younger & Fearing, 1999, by Ramsey et al., 2005). In addition, there is a lag between when infants recognize that female voices are associated with female faces and when male voices are associated with male faces; infants reliably match female faces and voices at 9 months (Poulin-Dubois, Serbin, Kenyon, & Derbyshire, 1994) but do not reliably match male faces and voices until 18 months. Even at 18 months, infants are more accurate at matching female faces and voices than they are at matching male faces and voices (Poulin-Dubois, Serbin, & Derbyshire, 1998).

This evidence could be interpreted in two ways: a) infants better recognize female faces because they have more experience with mothers than with fathers; or b) female face recognition develops earlier than male face recognition because humans have evolved to recognize a female caregiver at an early age. To date, there has been no attempt to replicate the above findings with mother-absent/father-present infants. Quinn et al. (2002) found that such infants show a weak preference for male faces (59%) but there is no indication that they are better at recognizing male faces than female ones.


Bestelmeyer, P.E.G., B.C. Jones, L.M. DeBruine, A.C. Little, D.I. Perrett, A. Schneider, L.L.M. Welling, & C.A. Conway. (2008). Sex-contingent face aftereffects depend on perceptual category rather than structural encoding, Cognition, 107, 353-365.

Duchaine, B.C., G. Yovel, E.J. Butterworth, & K. Nakayama. (2006). Prosopagnosia as an impairment to face-specific mechanisms: Elimination of the alternative hypotheses in a developmental case, Cognitive Neuropsychology,

Farah, M.J. (1996). Is face recognition ‘special’? Evidence from neuropsychology, Behavioural Brain Research, 76, 181-189.

Jaquet, E. (2007). Perceptual aftereffects reveal dissociable adaptive coding of faces of different races and sexes, PhD thesis, School of Psychology, University of Western Australia.

Little, A.C., L.M. DeBruine, & B.C. Jones. (2005). Sex-contingent face aftereffects suggest distinct neural populations code male and female faces, Proceedings of the Royal Society of London, Series B, 272, 2283-2287.

Pascalis, O., & D.J. Kelly. (2008). Face processing, in M. Haith & J. Benson (eds.) Encyclopedia of Infant and Early Childhood Development, pp. 471-478, Elsevier.

Quinn, P.C., Yahr, J., Kuhn, A., Slater, A.M., & Pascalis, O. (2002). Representation of the gender of human faces by infants: A preference for female. Perception, 31, 1109–1121.

Ramsey-Rennels, J.L., & J.H. Langlois. (2006). Infants’ differential processing of female and male faces, Current Directions in Psychological Science, 15, 59-62.

Regnault, D.L. (1966). Les sentences des pères du désert. Les Apophtegmes des pères. Sarthe: Abbaye Saint-Pierre de Solesmes.

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