Chapter 12 Update - September 2005 The development of face processing

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Nov 17, 2013 (3 years and 6 months ago)

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Chapter 12 Update
-

September 2005


The development of face processing


It used to be thought that children processed faces analytically until the age of 10,

at which age they began processing them configurally (Carey and Diamond, 1977).

That is, up unt
il the age of 10, children look at the individual features of a face when
trying to recognise them whereas children older than 10 look at the relations between
features on a face in order to recognise it. Research suggests that this is not the case and
th
at both adults and children process faces configurally (Flin, 1985; Baenninger, 1994).


There does seem to be an improvement in face recognition with age (Itier and Taylor,
2004). One way in which such developmental changes can be measured is by using
ERP
s

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one brain wave in particular, the N170, appears to be associated with face
recognition rather than general object recognition. It also appears to be larger, or
delayed, when recognising inverted rather than upright faces (the former is difficult and i
s
thought to be processed featurally rather than configurally).


To investigate whether changes in the N170 could be seen in children from 4 to 15 years
old, Taylor et al (2004) combined data from four of their already published ERP and face
processing stu
dies. The final sample comprised 425 children.


They found that the earlier ERP waves, such as the P100, which seems to reflect sensory
processing, were elicited in even very young children when viewing faces. However,

the appearance of the N170 elicited

by inverted faces started from mid
-
childhood

(mid
-
teens), suggesting that the ERP data reflect maturational development in the neural
systems that allow us to recognise faces.


A separate study suggests that the ability to see faces as wholes can be disr
upted by
visual deprivation during childhood (LeGrand
et al
, 2004). The researchers asked a
group of 12 right handed children who had been treated for bilateral congenital cataracts
to complete a face recognition task. These individuals had been deprived
of sight in early
childhood but had recovered the sense.


The face recognition task required participants to say whether the top halves of two faces
were the same when the bottom halves were different. In a second condition, the top and
bottom halves we
re misaligned so that the bottom half appeared to have been moved half
way long the page. Normal individuals had difficulty in making this decision, but
improved when the top and bottom halves were misaligned, suggesting that they
processed the face holis
tically, as a whole. Children who had been deprived of sight,
however, showed no evidence of holistic processing and performed better than controls
when the top and bottom halves were aligned
-

they were 20% more accurate and 175ms
faster. The data suggest
, according to the researchers, that holistic face processing can be
disrupted by visual deprivation that can last for as little as three months.


Baenninger, M.A. (1994). The development of face recognition: featural or
configurational processing?
Journa
l of Experimental Child Psychology
, 57, 377
-
396.


Carey, S. & Diamond, R. (1977). From piecemeal to configurational representation of
faces.
Science
, 195, 312
-
314.


Flin, R.H. (1985). Development of face recognition: An encoding switch?
British
Journal
of Psychology
, 76, 125
-
134.


LeGrand, R., Mondloch, C.J., Maurer, D. & Brent, H.P. (2004). Impairment in holistic
face processing following early visual deprivation.
Psychological Science
, 15, 11, 762
-
768.


Taylor, M.J., Batty, M. & Itier, R.J. (2004). T
he faces of development: A review of early
face processing over childhood.
Journal of Cognitive Neuroscience
, 16, 8, 1426
-
1442.