Motor Speech Disorders Associated With Neurogenic Disorders

Motor speech disorders associated with neurogenic disorders include aphasia, dysarthria, apraxia, and cognitive-communication impairments. These are all different types of communication problems that can be caused by neurological damage or disease. They can affect the way someone speaks and understand language.

Aphasia, dysarthria, apraxia, and cognitive-communication impairments are discussed in detail below.

Aphasia

Aphasia is an impairment of language, affecting the production or comprehension of speech and the ability to read or write. Aphasia is always due to injury. It can be caused by stroke, head trauma, brain tumor, infection (viral encephalitis), epilepsy surgery, and other brain conditions. The most common cause of aphasia in adults is stroke.

Dysarthria

Dysarthria is an impairment in articulation caused by neurologic disease that impairs control over muscles used in speech production. It can cause slurred speech with reduced intelligibility, i.e., drunken sailor voice. It is caused by damage to the nervous system or brain.

Apraxia

Apraxia refers to impaired ability to carry out purposeful learned movements despite intact motor function; examples are limb kinetic apraxias such as facial-oral apraxia (inability to coordinate mouth movements) and ideomotor limb apraxias such as dressing apraxia (inability to coordinate hand movements while dressing)

Cognitive-Communication Impairments

Cognitive-communication impairments refer to problems with pragmatic aspects of communication rather than linguistic ones—for example, difficulty initiating conversations or following rules for conversation turn-taking. These deficits frequently occur in patients with frontotemporal dementia.

The most common cause of acquired neurogenic communication disorders is stroke. Other causes include 

• Brain tumors
• Head injuries
• Multiple Sclerosis (MS)
• Amyotrophic Lateral Sclerosis (ALS)
• Parkinson’s disease (PD)
• Huntington’s disease (HD)
• Alzheimer’s Disease (AD)

Some people may also have these conditions at birth if they have certain genetic mutations, such as Down syndrome or fragile X syndrome.

To learn more about motor speech disorders and their causes, visit Disability Help’s blog section.