fMRI data for word-pair presentation
There are two general views regarding the organization of object knowledge. The featurebased view assumes that object knowledge is grounded in a widely distributed neural network in terms of sensory/function features (e.g., Warrington & Shallice, 1984), while the category-based view assumes in addition that object knowledge is organized by taxonomic and thematic categories (e.g., Schwartz et al., 2011). Using an fMRI adaptation paradigm, we compare predictions from the feature- and category-based views by examining the neural substrates recruited as subjects read word pairs that are identical, taxonomically related, thematically related or unrelated while controlling for the function features involved across the two categories. The feature-based view predicts that adaptation in function regions (i.e., left posterior middle temporal lobe, left premotor cortex) should be observed for related word pairs regardless of the taxonomic/thematic categories. In contrast, the category-based view generates the prediction that adaptation in the bilateral anterior temporal lobes should be observed for taxonomically related word pairs and adaptation in the left temporo-parietal junction should be observed for thematically related word pairs. By improving upon previous study designs and employing the fMRI adaptation task, this study has the potential to clarify the role of semantic categories and features in the organization of object knowledge.