Motor Speech Disorders in Degenerative Brain Disease

Frontotemporal dementia (FTD) is the second most common form of younger onset dementia after Alzheimer’s disease. There are three different forms of FTD, the most common being the behavioural variant (bvFTD), which affects behaviour and social cognition.

Background:

Primary progressive aphasia (PPA) is a form of language onset dementia, which includes the remaining two FTD subtypes: semantic PPA (svPPA) and non-fluent PPA (nfvPPA). Another form of PPA, the logopenic variant (lvPPA), is typically associated with Alzheimer’s disease.

Motor speech is a term used to describe the muscle movements used while speaking. Impaired motor speech is considered to be one of two core diagnostic features in nfvPPA and is usually not affected in svPPA and lvPPA. A high rate of speech changes has been reported in bvFTD; however, these changes have not been fully characterised.

Some people with FTD or PPA can develop motor speech impairments associated with other syndromes, such as motor-neurone disease and progressive supranuclear palsy. These syndromes commonly have a poorer prognosis. Comprehensive characterisation of the motor speech impairments in FTD and PPA will, therefore, aid the diagnostic process and assist in monitoring disease progression.

Methods:

Patients with FTD or PPA will undertake a speech assessment which will be examined perceptually by expert raters. Participants’ speech will also be recorded for analysis of acoustic features, such as vowel articulation, rate, prosody, and voice quality. Comparisons will be made between groups, and against a control group of healthy people. Acoustic speech measures will also be examined for correlation with measures of brain atrophy taken from their MRI scans.

Progress:

Participants have been recruited and speech data have been collected and analysed both perceptually and acoustically. Findings are currently being prepared for publication.

Publications:

Brodtmann, A., Pemberton, H., Darby, D., & Vogel, A.P. (2016). Diagnostic distortions: a case report of progressive apraxia of speech. Journal of Alzheimer’s Disease, 53 (1), 79-83.

Conference presentations:

Poole M. L, Brodtmann A., Darby D. and Vogel A. P. (2016). ‘Quantification of motor speech in primary progressive aphasia and frontotemporal dementia’ accepted for presentation at the 10th International Conference on Frontotemporal Dementias, Munich, Germany.

Poole M, Brodtmann A, Pemberton H, Low E, Darby D & Vogel AP (2015). Motor speech deficits in behavioural variant frontotemporal dementia. Front. Hum. Neurosci. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi:10.3389/conf.fnhum.2015.217.00396

Poole M. L., Brodtmann A., Darby D. and Vogel A. P. (2015). ‘A systematic review of motor speech and neuroimaging in frontotemporal dementia and primary progressive aphasia’ presented at Neuroscience 2015: Annual Meeting of the Society for Neuroscience, Chicago, USA.

Poole M. L., Brodtmann A, Darby D., and Vogel A. P. (2015). 'Objective monitoring of dysarthria in FTD-MND: a case study’ presented at the Seventh Annual Meeting of the Society for the Neurobiology of Language, Chicago, USA.

Project Collaborators:

A collaboration between The Florey Institute of Neuroscience and Mental Health, Monash University, Eastern Health, Matthew Poole and Dr Adam Vogel.