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Abstract:
Abstract: Recent theories of the development of face
processing emphasize the importance of early visual experience. de
Schonen and Mathivet (1989) argue that infants' bias to look toward
faces contributes to cortical specialization for faces in the right
hemisphere (e.g., configural processing). We compared individuals
with normal visual histories to patients deprived of early visual
experience by bilateral congenital cataracts. These cataracts
blocked all focused visual input until they were surgically removed
and the eyes were fitted with contact lenses (mean duration of
deprivation=3 months; range 1-6 months). In Experiment 1, normal
adults differentiated faces that varied either in the appearance of
their features (eyes and mouth) or the spacing of the features
(i.e., their configuration). Adults' accuracy for the face sets was
equal when presented upright; inversion disrupted performance on
the set with varied spacing (confirming this set taps configural
processing). In Experiment 2, 8 patients were tested after several
years of visual input following early deprivation (mean age=15
years; range 8 -20 years). Compared to age matched controls,
patients performed normally on the featural set (t(7)=1.39,
p>.10), but had abnormal difficulty differentiating faces from
the configural set (t(7)=2.65, p<.03). The findings to date
support the hypothesis that early visual experience plays an
important role in the development of the ability to process faces
based on configuration.
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