Abstract
Many studies have shown that neural populations in left occipitotemporal cortex (OT) show distinct fMRI responses to words as compared to other visual stimulus categories. Here we investigated the relationship between greater fMRI responses to words as compared to non-words, especially in left OT, and other differences measured using population receptive field (pRF) estimation. The pRF experiments also assessed differences in OT responses to single words versus words viewed in the context of sentences covering larger portions of the visual field. We found that using single words viewed at different locations during the pRF estimation experiments yielded greater word-selective voxels in left OT, and larger pRFs, than did using full-sentence text. We also observed differences in pRF eccentricity, with respect to stimulus type (words versus non-words) and cerebral hemisphere. Left OT showed greater word selectivity than right OT in both the pRF estimation experiments and corresponding independent localizers. Voxels in left OT that did not show word selectivity showed fewer centrally biased pRFs than did word-selective voxels in the same hemisphere. Our findings show that words and non-words are processed differently between the two hemispheres, and that these differences are directly related to word-selectivity across the visual field.