What is the cause of phonological errors in aphasic speech and what is the most effective method of therapy for these errors?

From October 2006 to January 2010
Project Leader(s): Dr Anne Whitworth, Professor David Howard
Staff: RA to the project - Heather Waldron
Sponsors: The Stroke Association Allied Health Professions Bursary

Clients with aphasia, an impairment of the understanding and use of language, typically make up a large proportion of the clinical caseload of speech and language therapists working with people following stroke. One common and frustrating symptom of aphasia is the production of phonological errors in speech, i.e. errors where some or all of the sounds in a word are substituted or omitted. One of the few recent studies to have reported successful therapy with this group of clients was carried out by Franklin, Buerk and Howard (2002). Clients with difficulties of this nature are the focus of this study.

This study aims to:
1.determine whether there are different subgroups of phonological processing difficulties that result in phonological production impairments in aphasia, and
2.establish whether people with phonological impairments in aphasia respond differentially to intervention aimed at improving auditory phonological analysis and self-monitoring abilities.

A case series of 10 clients with aphasia with phonological production impairments is being undertaken where clients are offered an intervention programme drawn from the principles set out by Franklin et al (2002). Therapy outcomes are being analysed for each participant in relation to their underlying phonological deficit in order to make hypotheses about the link between different patterns of underlying impairment and response to therapy, informing both psycholinguistic theory and intervention strategies in aphasia. The project will also aim to address the relationships between psycholinguistic assessments and real-life measures, and between generalisation on tasks and communication within real-life contexts. Previous research has highlighted the potential for conversational analysis to capture real-life change after therapy in aphasia (e.g. Rae, 2003), and it is anticipated that the current study can further investigate the usefulness of this approach as an outcome measure.


Professor David Howard
Research Development Professor