It is commonly acknowledged that word recognition relies primarily on the left hemisphere (LH) for right-handed individuals. However, the right hemisphere (RH) may also contribute to reading as it is often reported to possess certain, albeit limited, reading skills (see, for example, Brooks,
1973; Bryden & Allard,
1976; Cohen et al.,
2003; Coslett & Monsul,
1994; Deason & Marsolek,
2005; Gazzaniga, LeDoux, & Wilson,
1977; Marsolek, Kosslyn, & Squire,
1992; Sidtis, Volpe, Wilson, Rayport, & Gazzaniga,
1981). For instance, normal readers have been found to present an RH advantage for the recognition of words that are handwritten or that are printed in novel or script-type fonts (versus an LH advantage for words printed in standard print-type fonts; Brooks,
1973; Bryden & Allard,
1976; Deason & Marsolek,
2005). What's more, some individuals with brain lesions resulting in impaired reading have been found to rely on the RH for reading. In fact, Coslett and Monsul (
1994) studied participants who had an acquired dyslexia following a brain lesion to the LH and further impeded their reading abilities when they applied transcortical magnetic stimulation to inhibit their RH but not when they applied it to inhibit the left. Accordingly, Cohen et al. (
2003) found, in readers with acquired letter-by-letter dyslexia, that the RH's fusiform gyrus assumed some of the functional properties normally specific to the LH fusiform gyrus, thus supporting the hypothesis that residual visuo-orthographic processes may take place in the RH. Moreover, the RHs of some split-brain patients (i.e., patients who have undergone a corpus callosotomy) display a wide range of linguistic capacities, ranging from simple semantic matching to competent overt word recognition (such as in patient P.S.; Gazzaniga, LeDoux, & Wilson,
1977; and in patient V.P., Sidtis, Volpe, Wilson, Rayport, & Gazzaniga,
1981). These studies generally support the hypothesis that the visual processing of words by the RH may be useful for word recognition under certain circumstances. However, they also conclude that there is a clear advantage for word processing in the LH, and they underline the possibility that the visual processing of words may differ between the hemispheres.