ALS, Parkinson's, and MS: Progressive Diseases on the Praxis SLP Exam

Progressive neurological disease items on the Praxis 5331 test one skill: matching the disease pattern to the right dysarthria type and the right management philosophy. Restoration is not the goal — maintaining function and planning ahead is.

ALS

Amyotrophic lateral sclerosis involves both upper and lower motor neurons, producing mixed spastic-flaccid dysarthria. Expect hypernasality, imprecise consonants, strained-strangled voice, slow rate, tongue atrophy and fasciculations, and progressive dysphagia. Cognition is usually spared, though ALS-FTD overlap exists.

Management: proactive AAC, including voice banking and message banking while speech is still intelligible. Waiting until the patient is unintelligible is the wrong answer. Avoid fatiguing strengthening programs; energy conservation and diet modification with instrumental guidance are appropriate.

Parkinson disease

Basal ganglia degeneration produces hypokinetic dysarthria: reduced loudness, monopitch and monoloudness, breathiness, short rushes of speech, and imprecise consonants. Patients typically underestimate their own quietness — a sensory recalibration problem.

LSVT LOUD is the best-supported intervention, using high-effort, high-intensity loudness training with recalibration. Swallowing decline is common and often silent; screen regularly.

Multiple sclerosis

Demyelinating lesions scattered across the CNS produce ataxic-spastic mixed dysarthria in many patients, with scanning speech, impaired loudness control, and harshness. Fatigue and heat sensitivity shape session scheduling; cognitive-communication deficits in processing speed and memory are common.

Huntington disease

A hyperkinetic disorder with involuntary choreiform movement producing hyperkinetic dysarthria: variable rate, sudden loudness bursts, prolonged intervals, and distorted vowels, plus progressive cognitive decline.

Progressive dementias

Primary progressive aphasia variants (nonfluent/agrammatic, semantic, logopenic) and Alzheimer disease call for external memory supports, spaced retrieval, errorless learning, and caregiver training — covered in our dementia guide.

The shared management principles

• Establish baseline early and monitor at intervals.
• Introduce AAC and swallowing safety before crisis, not after.
• Prioritize functional communication and quality of life over accuracy metrics.
• Counsel patient and family together, including advance planning.
• Match session demands to fatigue patterns.

Pair this with the motor speech disorders guide for the full dysarthria classification table.