topics: |  psychology | perception | reference

Perceptual Development: Face Perception

		 *by Paul C. Quinn, Kang Lee, Olivier Pascalis, and Alan M. Slater

Newborn face perception abilities

Newborn infants, just a few minutes from birth, will track with their eyes
a schematic visual stimulus resembling a face more than they will track a
stimulus that has the external shape of the head but has the internal
features of the face scrambled. This result supports the idea that newborn
infants enter the world with an internal representation of a face, although
some have suggested that the information in the representation may be
relatively coarse, consisting of three high-contrast blobs in the correct
relative locations...  However, the possibility that the initial face
representation may be more elaborate is suggested by the finding that
newborn infants will imitate facial gestures (such as mouth opening and
tongue protrusion) that they see an adult modeling.

Development of Face Perception in the First Year

the question arises as to how sensitivity develops to the individual features
versus sensitivity to the structural whole that incorporates the spatial
relations among the features. ... for structural processing, there is the
question of how infants come to process first-order relations (i.e.,
categorical spatial relations—the eyes above the nose) and second-order
relations (i.e., metric spatial relations— the distance between the eyes and
the nose).  The expertise that adults have for processing faces is believed
to be associated with sensitivity to second-order relations. Initial
sensitivity to both first- and second-order relations is present in infancy,
although full development of sensitivity to second-order relations to
adultlike levels may follow a protracted course lasting even into
adolescence.

There is also a growing literature on how infants come to process social
attributes of faces during their first year (e.g., identity, emotion, gender,
race, attractiveness). This literature initially focused on the question of
mother–stranger differentiation with its implications for the development of
attachment.  This research collectively suggests that the preference for
mother over stranger is manifest in the late third trimester in the auditory
domain and shortly after birth in the visual and olfactory domains. The
visual preference is facilitated by increased exposure to the mother’s face
and voice in the first few hours and days after birth.

Emotion from faces

Taken together, the studies suggest that infants may process emotion
information more efficiently from dynamic and familiar faces, and that
multimodal information may contribute to infants’ developing understanding of
the “meaning” of emotion by lessening the likelihood that attention will be
focused on modality-specific cues (e.g., toothiness in the visual input). In
addition, infants can categorize emotional expressions across variation in
the intensity of the emotion and the individuals depicting the emotion, and
also display differential responsiveness to classes of emotion through
spontaneous preference (e.g., fearful faces are preferred to happy ones).

Gender and Race: familiarity preference

by three months of age, infants prefer the gender of the primary caregiver
and same- to other-race faces, with both preferences driven by differential
experience.  Specifically, three-month-olds reared by a female caregiver and
presented with a series of female faces preferred a novel over familiar
female face; however, when presented with male faces, there was no
differential preference for a novel over familiar male face. In addition,
although threemonth- old Caucasian infants exposed predominantly to Caucasian
faces performed as well on a recognition memory task involving either own- or
other-race faces, nine-month-old Caucasian infants demonstrated recognition
memory only for Caucasian faces. The recognition advantage for same-race
faces and its time course of development has also been observed for human
infants viewing same- versus other-species of faces (humans versus monkeys).

Another social dimension of faces that infants respond to is physical
attractiveness. In particular, infants will spend more time looking at
attractive faces (as judged by adults) when these are shown paired with less
attractive human faces. Infant preference for attractive faces has been
observed for a range of human faces, including Caucasian and African American
adult female faces, adult male faces, and infant faces. The attractiveness
effect can be demonstrated even in newborn infants: It is orientation
dependent, occurring for upright but not inverted faces, and it is driven by
the internal features of faces.

A question of interest is whether the attractiveness preference in infants is
dependent on perceptual learning mechanisms or whether it reflects the face
representation that newborn infants bring to the learning situation for
faces. The learning account of the attractiveness effect is couched in terms
of an averaging process known as prototype formation: When several faces are
averaged, adults perceive the resulting face as more attractive than any of
the individual faces. By this learning account, infant preference for
attractive faces may reflect a preference for faces similar to a composite of
the faces seen since birth. This account can apply even to the results
obtained with the newborn infants, given that those infants were two to three
days old at testing, and would likely have experienced a multitude of faces
even during that short time frame. In contrast, by a nativist account,
newborn infants could enter the world with a face representation, and
attractive faces are preferred because they more closely match this
representation. This representation could still be in the form of a
prototype, except that it would have been formed through evolutionary
mechanisms. Consistent with the nativist account, young infants have also
been found to prefer attractive over unattractive nonhuman animal faces for
which they had no previous experience (i.e., cats, tigers).

The finding that the attractiveness preference in infants extends beyond
conspecifics also suggests that it is not reflective of an adaptation to mate
choice, as some have suggested, but may point toward the operation of more
general mechanisms that process a family of preferred perceptual features
that includes, but may not be limited to, particular features, such as large
eyes, and the complex geometric attributes that characterize the spatial
relations among the features, such as their location (e.g., height) and
arrangement (e.g., symmetry) within the whole. Thus, just as the perception
of some social attributes of faces (i.e., identity, emotion, gender, and
race) seems to be driven by experience, the perception of other social
attributes of faces (i.e., attractiveness) may be determined by the initial
settings of our perceptual systems.