Dejerine's reading area revisited with intracranial EEG: Selective responses to letter strings

Université Pierre et Marie Curie University (M. Sharman), Paris
Neurology (Impact Factor: 8.29). 02/2013; 80(6):602-603. DOI: 10.1212/WNL.0b013e31828154d9
Source: PubMed


The visual word form area in the ventral occipitotemporal cortex develops with acquisition of reading skills. It is debated whether this region is specialized for reading(1) or is rather a general-purpose area associating visual form (words, objects) with meaning. An outline of this debate can be found in appendix e-1 on the Neurology® Web site at We recorded intracranial EEG in 2 patients with epilepsy (figures 1, e-1, and e-2) and found neural populations responding almost exclusively to letter strings, over 500% of all other responses. With the exception of the fusiform face area, such specific responses have never been described before in the human visual system.(2) Strong specialization in the human brain can thus be achieved also through cultural learning.

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    • "Finally, previous electrophysiological studies nicely demonstrated that the VOTC is activated at approximately 200 ms post word onset as can be evidenced both by ERPs (Nobre et al., 1994) and BG response (Hamame et al., 2013). This early activation in the VOTC fits well with the role of this region in processing pre-lexical and orthographic sensory input as demonstrated by fMRI (Levy et al., 2008). "
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    ABSTRACT: Prior investigations of functional specialization have focused on the response profiles of particular brain regions. Given the growing emphasis on regional covariation, we propose to reframe these questions in terms of brain 'networks' (collections of regions jointly engaged by some mental process). Despite the challenges that investigations of the language network face, a network approach may prove useful in understanding the cognitive architecture of language. We propose that a language network plausibly includes a functionally specialized 'core' (brain regions that coactivate with each other during language processing) and a domain-general 'periphery' (a set of brain regions that may coactivate with the language core regions at some times but with other specialized systems at other times, depending on task demands). Framing the debate around network properties such as this may prove to be a more fruitful way to advance our understanding of the neurobiology of language.
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