Reading requires the neural integration of visual word form information that is split between our retinal hemifields. We examined multiple visual cortical areas involved in this process by measuring fMRI responses while observers viewed words that changed or repeated in one or both hemifields. We were specifically interested in identifying brain areas that exhibit decreased fMRI responses as a result of repeated versus changing visual word form information in each visual hemifield. Our method yielded highly significant effects of word repetition in a previously reported visual word form area (VWFA) in occipitotemporal cortex, which represents hemifield-split words as whole units. We also identified a more posterior occipital word form area (OWFA), which represents word form information in the right and left hemifields independently and is thus both functionally and anatomically distinct from the VWFA. Both the VWFA and the OWFA were left-lateralized in our study and strikingly symmetric in anatomical location relative to known face-selective visual cortical areas in the right hemisphere. Our findings are consistent with the observation that category-selective visual areas come in pairs and support the view that neural mechanisms in left visual cortex--especially those that evolved to support the visual processing of faces--are developmentally malleable and become incorporated into a left-lateralized visual word form network that supports rapid word recognition and reading.

Movements of the fingers, hand and arm involve overlapping neural representations in primary motor cortex (M1). Monkey M1 exhibits a core-surround organisation in which cortical representation of the hand and fingers is surrounded by representations of the wrist, elbow and shoulder. A potentially homologous organisation in human M1 has only been observed in a single study, a functional MRI (fMRI) study by [J.D. Meier, T.N. Aflalo, S. Kastner & M.S. Graziano.(2008) J Neurophysiol, 100(4), 1800-1812]. The results of their study suggested a double representation of the wrist in human M1, an unprecedented finding. Our purpose was to document and simultaneously provide evidence that would extend the presence of double representation of the wrist to that of the elbow. Using fMRI, we observed somatotopic maps in M1 and the supplementary motor area (SMA), the only other cortical area that showed robust within-limb somatotopy during self-timed finger, wrist and elbow movements. We observed double wrist and elbow representation that bracketed finger fMRI responses in M1 and the SMA. Our results show that the cortical locations of these double representations are well predicted by local cortical anatomy. Double representation of the wrist and elbow is important because it violates the traditional somatotopic progression in M1 but it is consistent with the representation of synergistic movements involving adjacent effectors.