Taxonomic and Thematic Organization of Nouns in Aphasia: Evidence Through Discrete Association Task

Abstract

Lexical semantic organization is often probed in children and adults. The organization would definitely vary as a function of age. The organization which is assumed to operate on taxonomic means in children is found to shift to thematic means by adulthood. Lexical semantic organization can be studied by employing various methods such as confrontation naming, semantic fluency task, etc. Word association task, where the participant is asked to list as many things which would come to his/her mind after listening to the target word, is one of the most influential methods in probing lexical semantic organization. The task is considered to be discrete when the participant is confined in terms of the number of responses. The present study used this method in studying lexical semantic organization in persons with aphasia. Six participants with aphasia, with some quantum of verbal output, were considered. Twenty concrete, pictureable, frequently used noun forms in Kannada were used as stimuli and the task of the participant was to come out with five words which would come to their mind after hearing the target word. It was found the organization was more taxonomic in nature indicating that the organization would have been hampered as a consequence of stroke and was in the verge of reorganization.

Keywords: taxonomic organization, thematic organization aphasia

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