'Dysarthria' is a
speech disorder resulting from
neurological injury, characterised by poor articulation (cf
aphasia: disorder of the content of speech). Any of the speech subsystems (
respiration,
phonation,
resonance,
prosody,
articulation and movements of jaw and tongue) can be affected.
Disarthic speech is due to some disorder in the nervous system, which in turn hinders control over for example tongue, throat, lips or lungs. Swallowing problems,
dysphagia, are often present.
Cranial nerves that control these muscles include the
facial nerve (VII), the
glossopharyngeal nerve (IX), the
vagus nerve (X), and the
hypoglossal nerve (XII).
Classification
Dysarthrias are classified in multiple ways based on the presentation of symptoms. Specific dysarthrias include
Spastic,
Flaccid,
Hyperkinetic,
Hypokinetic,
Ataxic, Unilateral
upper motor neuron, and Mixed dysarthria.
Causes
The reasons behind dysarthria can be many; among the diseases are
ALS,
Parkinson's disease, cranial nerve lesions, chorea,
prion protein related diseases, and
cerebral palsy. Dysarthria can also be an early symptom of stroke. More common causes are
intoxication and
anesthesia, although these are transient. Another possibility is
myasthenia gravis.
Treatment
The articulation problems that dysarthria causes can be treated together with a
speech language pathologist using a range of techniques which sometimes includes strengthening the speech musculature. Devices that make coping with dysarthria easier include
speech synthesis software and
text-based telephones.
References
★
Neuroanatomy: an atlas of structures, sections, and systems, Haines, Duane, , , Lippincott Williams & Wilkins, 2004,
★
Motor Speech Disorders: Substrates, Differential Diagnosis, And Management. 2nd edition., Duffy, Joseph R, , , C.V. Mosby, 2005,