Visual word form area

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The visual word form area (VWFA) is a functional region of the fusiform gyrus that is hypothesized to be involved in identifying words and letters from lower-level shape images, prior to association with phonology or semantics.[1][2] Because the alphabet is relatively new in human evolution, it is unlikely that this region developed as a result of selection pressures related to word recognition per se; however, this region may be highly specialized for certain types of shapes that occur naturally in the environment and are therefore likely to surface within written language.[citation needed]

In addition to word recognition, the VWFA may participate in higher-level processing of word meaning.[3]

In 2003, functional imaging experiments have also raised doubts about whether the VWFA is an actual region.[4] This skepticism has largely disappeared, however there seems to be much variability in its size. An area that may fall within this mental organ in one person may fall outside it in someone else [5]

Anomalies in the activation of this region have been linked to reading disorders.[6] If the area is subjected to a surgical lesion, the patient will suffer a clear impairment to reading ability but not to recognition of objects, names, or faces or to general language abilities. There will be some improvement over the next six months, but reading will still take twice as long as it had before surgery.[7]

References[edit]

  1. ^ Dehaene, Stanislas; Cohen, Laurent (2011). "The unique role of the visual word form area in reading". Trends in Cognitive Sciences 15 (6): 254–62. doi:10.1016/j.tics.2011.04.003. PMID 21592844. 
  2. ^ McCandliss, Bruce D.; Cohen, Laurent; Dehaene, Stanislas (2003). "The visual word form area: Expertise for reading in the fusiform gyrus". Trends in Cognitive Sciences 7 (7): 293–299. doi:10.1016/S1364-6613(03)00134-7. PMID 12860187. 
  3. ^ Levy, Jonathan; Vidal, Juan R.; Oostenveld, Robert; FitzPatrick, Ian; Démonet, Jean-François; Fries, Pascal (September 2013). "Alpha-band suppression in the visual word form area as a functional bottleneck to consciousness". NeuroImage 78: 33–45. doi:10.1016/j.neuroimage.2013.04.020. 
  4. ^ Price, Cathy J; Devlin, Joseph T (2003). "The myth of the visual word form area". NeuroImage 19 (3): 473–81. doi:10.1016/S1053-8119(03)00084-3. PMID 12880781. 
  5. ^ Glezer, L. S.; Riesenhuber, M. (3 July 2013). "Individual Variability in Location Impacts Orthographic Selectivity in the "Visual Word Form Area"". Journal of Neuroscience 33 (27): 11221–11226. doi:10.1523/JNEUROSCI.5002-12.2013. 
  6. ^ James S. Adelman (2012). Visual Word Recognition: Models and Methods, Orthography and Phonology. Psychology Press. p. 28. ISBN 978-1-84872-058-9. 
  7. ^ Gaillard, Raphaël; Naccache, Lionel; Pinel, Philippe; Clémenceau, Stéphane; Volle, Emmanuelle; Hasboun, Dominique; Dupont, Sophie; Baulac, Michel; Dehaene, Stanislas; Adam, Claude (20 April 2006). "Direct Intracranial, fMRI, and Lesion Evidence for the Causal Role of Left Inferotemporal Cortex in Reading". Neuron 50 (2): 191–204. doi:10.1016/j.neuron.2006.03.031.