Zusammenfassung
Cohen and Dehaene et al. proposed that the Visual Word Form Area (VWFA)
in the left midfusiform gyrus, contrary to its name, is limited to
the extraction of an abstract letter string and not involved in proper
visual word recognition. We examined this prelexical function of
the VWFA by a parametric block design with five levels of written
word frequency. The lowest level was represented by pseudowords and
the highest level by words of very high frequency. Contrary to the
assumed prelexical function of the VWFA, increasing frequency was
associated with decreasing brain activation in a large posterior
cluster of the left hemisphere including middle and posterior fusiform
regions. The same negative relation between frequency and activation
was found in several left frontal clusters. The relation of increasing
frequency and decreasing activation in occipitotemporal regions corresponds
to a similar relation in the same brain regions found by studies
which experimentally manipulated object or face familiarity. This
convergence suggests that fusiform regions are specialized for extracting
and storing abstract patterns when processing visual objects and
these patterns serve as recognition units in subsequent encounters
with the same objects.
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