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Abstract:
The double dissociation between prosopagnosia, a face
recognition deficit occurring after brain damage, and visual object
agnosia, difficulty recognizing other kinds of complex objects,
indicates that face and non-face object recognition may be served
by partially independent mechanisms in the brain. Such a
dissociation could be the result of a competitive learning
mechanism that, during development, devotes neural resources to the
tasks they are best at performing. Studies of normal adult
performance on face and object recognition tasks seem to indicate
that face recognition is primarily configural, involving the low
spatial frequency information present in a stimulus over relatively
large distances, whereas object recognition is primarily featural,
involving analysis of the object's parts using local, high spatial
frequency information. In a feed-forward computational model of
visual processing, two modules compete to classify input stimuli;
when one module receives low spatial frequency information and the
other receives high spatial frequency information, the
low-frequency module shows a strong specialization for face
recognition in a combined face identification/object classification
task. The series of experiments shows that the fine discrimination
necessary for distinguishing members of a visually homogeneous
class such as faces relies heavily on the low spatial frequencies
present in a stimulus.
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