The different frameworks underlying abstract and concrete knowledge: evidence from a bilingual patient with a semantic refractory access dysphasia.

We report the case of a bilingual patient (IRQ) who acquired a semantic refractory access dysphasia following a middle cerebral artery stroke. In a series of spoken word-written word matching tasks, the degree of semantic similarity between target and distractor items was found to affect the accuracy of IRQ's identification of concrete but not abstract words. By contrast, the degree of semantic association between target and distractor items was found to affect response accuracy when identifying abstract but not concrete words. These results provide further corroboration for the notion that abstract concepts are supported by an associative representational network whereas concrete concepts are supported by a categorical representational framework. We also demonstrate an equivalent refractory deficit of comprehension in both English and Arabic. In addition, we provide the first documented evidence of a category-specific refractory deficit of knowledge for abstract words.