Dysarthria & Motor Speech Disorders

What is a motor speech disorder (MSD)? “speech disorders resulting from neurologic impairments affecting planning, programming, control and execution of speech.” (Duffy, 2013)

What is dysarthria? “group of neurologic speech disorders that reflect abnormalities in the strength, speed, range, steadiness, tone, or accuracy of movements required for the breathing, phonatory, resonantory, articulatory, or prosodic aspects of speech production.” (Duffy, 2013)

1. Dysarthria is a result of a neurologic problem.
2. It is a disorder of movement. 
3. It is categorized by different types with it’s own perceptual characteristics and presumably a different underlying neuropathophysiology. You can categorize the dysarthrias by the localization of the casual disorder (determine where the lesion in the brain is). 

Assessing and Managing Dysarthria:

Types of Dysarthria include the following: Flaccid, Spastic, Ataxic, Hypokinetic, Hyperkinetic and Unilateral Upper Motor Neuron. Click on the following link to learn more about distinguishing perceptual characteristics and physiologic findings by dysarthria type: https://www.asha.org/practice-portal/clinical-topics/dysarthria-in-adults/distinguishing-perceptual-characteristics/

To assess dysarthria, one must include an oral mechanism/cranial nerve evaluation. An evaluation report should include how the client’s dysarthria is impacting their intelligibility (the degree to which a listener understands the speaker). You should determine how the individual is communicating their wants/needs (e.g., Can they ask for their medication? Can their doctor understand what they’re saying?) and how intelligible they sound to an unfamiliar listener. This will ultimately help guide developing treatment goals.

Assessment tools are the following: 

• Speech Intelligibility Test (SIT; Beukelman et al., 2007) Mayo Clinic (informal) (Duffy, 2005)
• Dysarthria Examination Battery (Drummond, 1993) Dysarthria Profile (Robertson, 1982
• Frenchay Dysarthria Assessment-2nd Edition (FDA-2; Enderby & Palmer, 2008)

Treatments targets include the following:

• Respiration: slow, restricted, weak, or uncoordinated muscles activity used in breathing for speech.
• Resonance: amplifying the sound by changing size, shape, and number of cavities through which it passes
• Phonation: producing sound in the larynx
• Articulation: movement of speech muscles to make speech sounds 
• Prosody: changes in intonation, stress and rhythm/rate in speech 

Treatment options:

Respiration:

• Diaphragmatic breathing, postural adjustments (e.g., is the person slouched down? Is posture normal? Does the person complain of shortness of breath when speaking?), training inhalation/exhalation coordination for speech such as expiratory muscle strength training (Laciuga et al., 2014), phrase grouping strategies. 

Resonance: 

• Prosthetic devices if appropriate, behavioral intervention

Phonation:

• Loudness training with Lee Silverman Voice Treatment (LSVT), effective for persons with Parkinson’s Disease (must be trained/certified), Vocal function exercises (Stemple et al., 2014)

Articulation:

• Training over-articulation and using “big and exaggerated speech movements”, Be Clear Speech Treatment (Park, S., et al, 2016)

Prosody:

• Training pacing strategies with/without metronome to target prosody (Blanchet & Snyder, 2010)

Tip: These are only some, not all treatment options/strategies. It is helpful to read systematic reviews (such as the one listed below) to stay up-to-date on current evidence based practices. 

• Emma Finch, Anna F. Rumbach & Stacie Park (2020) Speech pathology management of non-progressive dysarthria: a systematic review of the literature, Disability and Rehabilitation, 42:3, 296-306, DOI: 10.1080/09638288.2018.1497714

Additional resources:

https://www.asha.org/Practice-Portal/Clinical-Topics/Dysarthria-in-Adults

Duffy. (2013). Motor Speech Disorders. Elsevier Gezondheidszorg.

References

Duffy. (2013). Motor Speech Disorders. Elsevier Gezondheidszorg.

Laciuga, H., Rosenbek, J. C., Davenport, P. W., & Sapienza, C. M. (2014). Functional outcomes associated with expiratory muscle strength training: narrative review. Journal of Rehabilitation Research & Development, 51(4), 535-546.

Mahler, L. A., Ramig, L. O., & Fox, C. (2015). Evidence-based treatment of voice and speech disorders in Parkinson disease. Current opinion in otolaryngology & head and neck surgery, 23(3), 209-215

McCullough, G. H., Zraick, R. I., Balou, S., Pickett, H. C., Rangarathnam, B., & Tulunay-Ugur, O. E. (2012). Treatment of laryngeal hyperfunction with flow phonation: A pilot study. Journal of Laryngology and Voice, 2(2), 64-69.

Park S, Theodoros D, Finch E, Cardell E. Be Clear: A New Intensive Speech Treatment for Adults With Nonprogressive Dysarthria. Am J Speech Lang Pathol. 2016 Feb;25(1):97-110. doi: 10.1044/2015_AJSLP-14-0113. PMID: 26882004.

Stemple, J. C., Roy, N., & Klaben, B. K. (2014). Clinical voice pathology: Theory and management: Plural Publishing.