Cognitive neuropsychology of acquired language disorders in a Turkish-English bilingual case.

Research addressing the cognitive neuropsychology of acquired language disorders in Turkish such as aphasia, dysphasia and dysgraphia has only just begun to flourish (Raman & Weekes, 2003; 2005; 2006 and Weekes & Raman, in press). Unlike many alphabetic writing systems reported to date, Turkish orthography is characterized by totally predictable mappings between orthography and phonology that has implications for the presentation of language disorders, their diagnosis and rehabilitation. In this paper, we report a series of experimental investigations with patient BRB, a 67 year old native Turkish speaking male who suffered a left temporal CVA. We report our findings from lexical and nonlexical processing tasks including oral reading, repetition and writing to dictation whilst critically manipulating several psycholinguistic variables such as age of acquisition, word regularity, imageability, grammatical class in Turkish (L1) and English (L2) as BRB was Turkish-English bilingual. Significant main effects of language and task as well as interactions between language and task were observed, e.g., BRB’s repetition, reading and writing was overall better in L1 than L2 object naming was better in L2 than L1 but only with high imageability words. The implications of findings will be discussed in relation to the development of much needed diagnostic tools and rehabilitation programms in Turkish from a cognitive neuropsychology perspective.

First presented at the 10th International Conference on Cognitive Neuroscience, Bodrum, Turkey, 2008.