Functional MRI scans have shown that the area specifically activates when people read, as opposed to recognizing other objects, such as faces or houses. And people with lesions in the region lose the ability to recognize whole words--reduced to letter-by-letter reading. However, fMRI studies cannot demonstrate a causal role for the VWFA, and lesions involving the VWFA invariably involved other regions as well.
Now, a patient whose surgery to relieve epilepsy specifically disrupted the VWFA has given researchers, led by Laurent Cohen of the Hôpital de la Salpêtrière, an opportunity to demonstrate that the region does indeed play a causal role in the ability to recognize words.
The researchers reported in the April 20, 2006, issue of Neuron the results of reading, language, and object recognition tests both before and after the surgery on the 46-year-old man. They found his reading capability before surgery to be normal. However, tests after surgery showed very different results.
"Although we studied reading more extensively than the perception of other types of visual stimuli, our patient presented a clear-cut reading impairment following surgery, while his performance remained flawless in object recognition and naming, face processing, and general language abilities," reported the researchers. "Such selectivity may be difficult to observe in patients with more customary lesions resulting from strokes or tumors, which often affect a larger extent of cortex and white matter. The small size of the present lesion thus provides precious support to the idea of partial regional selectivity for