Vol. 17, No. 1
In search of Noun-Verb dissociations in aphasia across three processing tasks
1Center for Research in Language, University of California, San Diego; 2SDSU/UCSD Joint Doctoral Program in Language & Communicative Disorders; 3Department of Cognitive Science, University of California, San Diego; 4VA Medical Center, Martinez
This paper presents work we conducted in our search to understand how the brain is organized for meaning (both linguistic and non-linguistic). We address the notion of noun-verb dissociations, which has often been studied but remains controversial. We tested a group of 21 patients with aphasia (Anomic, Broca and Wernicke) along with a group of 20 college-aged and older control participants on a word production battery which counterbalanced noun and verb stimuli across three popular word-processing tasks: picture-naming (PN), word reading and repetition (WRP, or word repetition paradigm). Several important variables were controlled for during item selection and in post-hoc analyses, e.g., word frequency, age of acquisition, naming difficulty and ambiguity, among others. Results revealed that PN was the most difficult task across groups, and also the only condition in which any significant noun-verb differences were observed (contrary to similar studies using blocked noun-only or verb-only stimuli). In addition, all groups displayed a noun advantage (commonly seen for healthy participants and contrary to the notion of a verb advantage in certain brain-injured groups). These noun-verb results, acquired with a flexible, highly applicable stimuli set, set the stage for subsequent analyses focusing on deeper, sensorimotor-based distinctions in language processing.