An investigation of levels of processing in single word production in aphasia (NEST)

(See also KeyPhone)
 

The project involves a series of single case studies investigating single word production in aphasia. Many people with aphasia have difficulties in word retrieval. Currently the difficulty is viewed as a problem with semantics or a problem with phonological representations. A third possibility exists however: that a word finding problem may arise due to difficulties in accessing the syntactic representation of the word. For noun production this involves knowledge of the determiners which may legally combine with that word. For example we can say 'some water' but not 'a water' and 'a cat' but not 'some cat'.

Assessment materials do not exist to investigate this aspect of language processing, so part of the project has involved the development of new materials, some of which are computer-based, to probe processing at the syntactic level. Six people with aphasia are currently enrolled in the study. After completion of the assessment research participants are offered a phase of therapy. The therapy seeks to facilitate production of appropriate determiners with target nouns. The hypothesis is that delivering therapy to this level of processing rather than to the single word level may lead to better generalisation to connected speech.

Results so far indicate:

• that certain people with aphasia have little knowledge of noun phrase syntax, shown in both input and output tasks and that this deficit may be a cause of word production failure;
• and that dissociations can arise between different noun types as a result of brain damage, here between mass and count nouns.

Three people are about to embark upon the therapy and outcomes of this will be reported as they emerge.

Best, W., & Herbert, R. (2004). Missing 'some' thing. An investigation of levels of processing in spoken word production in acquired aphasia. Paper presented at the Forum for Research in Language and Literacy, Essex, UK.

Herbert, R., & Best, W. (2004a). An investigation of levels of processing in spoken word production in acquired aphasia. Paper presented at the British Aphasiology Society Work in Progress meeting, London, UK.

Herbert, R., & Best, W. (2004b). Spoken word production in aphasia: what mass and count nouns can reveal. Poster presented at one day conference "The Architecture of the Language Faculty" at University College London, London, UK.