The information below has been adapted from http://en.wikipedia.org/wiki/Dysarthria#Causes.

[Note that a speech and language therapist is referred to as a speech and language pathologist in the USA]

The causes of dysarthria can be many, including toxic, metabolic, degenerative diseases (such as Parkinsonism, ALS (MND), Huntington’s Disease, Niemann Pick disease, Ataxia etc.), traumatic brain injury, or thrombotic or embolic stroke. These result in lesions to key areas of the brain involved in planning, executing, or regulating motor operations in the skeletal muscles (i.e. limb muscles), including the head and neck muscles, dysfunction of which characterises dysarthria.

These can result in dysfunction, or failure of:

• the motoror somatosensory cortex of the brain (the past that processes sensory information)
• corticobulbar pathways, which send signals to help move facial and neck muscles
• the cerebellum
• basal nuclei, which help control functions such as eye movements, decision-making and memory
• The brainstem
• the neuro-muscular junction, which blocks the nervous system’s ability to activate muscles and enable a person to make the correct range and strength of movements

Causes:

• Brain tumour
• Cerebral palsy
• Guillain-Barre syndrome
• Head injury
• Hypothermia
• Lyme disease
• Multiple sclerosis
• Parkinson’s disease
• Stroke
• Wilson’s disease
• Intercranial Hypertension (formerly known as Pseudotumor Cerebri)
• Tay-Sachs, and Late Onset Tay-Sachs (LOTS), disease.

You can find further information in our factsheet – dysarthria and dysphasia