The myth of the visual word form area.
Neuroimage, (2003)DOI: http://dx.doi.org/10.1016/S1053-8119(03)00084-3
Abstract
Recent functional imaging studies have referred to a posterior region
of the left midfusiform gyrus as the "visual word form area" (VWFA).
We review the evidence for this claim and argue that neither the
neuropsychological nor neuroimaging data are consistent with a cortical
region specialized for visual word form representations. Specifically,
there are no reported cases of pure alexia who have deficits limited
to visual word form processing and damage limited to the left midfusiform.
In addition, we present functional imaging data to demonstrate that
the so-called VWFA is activated by normal subjects during tasks that
do not engage visual word form processing such as naming colors,
naming pictures, reading Braille, repeating auditory words, and making
manual action responses to pictures of meaningless objects. If the
midfusiform region has a single function that underlies all these
tasks, then it does not correspond to visual word form processing.
On the other hand, if the region participates in several functions
as defined by its interactions with other cortical areas, then identifying
the neural system sustaining visual word form representations requires
identification of the set of regions involved. We conclude that there
is no evidence that visual word form representations are subtended
by a single patch of neuronal cortex and it is misleading to label
the left midfusiform region as the visual word form area.