Dysarthria is a motor speech disorder caused by neurological injury, disease, or other conditions affecting the muscles and motor systems used for speech. It can affect breathing, voice, articulation, resonance, speech rate, and prosody , resulting in speech that may sound unclear or unnatural.

Dysarthria can occur after conditions such as stroke, Parkinson’s disease, traumatic brain injury, multiple sclerosis, ALS, Huntington’s disease, and other neurological disorders .

Common Signs of Dysarthria

A person with dysarthria may experience:

• Slurred or unclear speech

• Imprecise consonants

• Reduced speech intelligibility

• Speaking too quickly or slowly

• Short or rushed bursts of speech

• Reduced loudness

• Monotone or reduced pitch variation

• Breathiness, hoarseness, or strained voice

• Difficulty controlling pitch or volume

• Nasal or hypernasal speech

• Changes in speech rhythm and stress

• Speech that becomes less clear with fatigue

The specific symptoms depend on the type and underlying cause of dysarthria.

What Causes Dysarthria?

Dysarthria can result from neurological conditions affecting the systems responsible for speech movement and coordination.

Common causes include:

• Stroke

• Parkinson’s disease

• Traumatic brain injury

• Multiple sclerosis

• ALS

• Huntington’s disease

• Cerebellar disorders

• Neuromuscular disorders

• Brain tumors

• Other neurological conditions

Dysarthria may also occur alongside aphasia, apraxia of speech, cognitive-communication difficulties, or swallowing disorders .

Dysarthria vs Aphasia vs Apraxia of Speech

These conditions can sometimes sound similar but affect different aspects of communication.

Dysarthria: primarily affects the motor execution of speech , resulting in changes in clarity, voice, rate, or prosody.

Aphasia: primarily affects language , including understanding or expressing language.

Apraxia of Speech: involves difficulty with planning and programming the movements required for speech .

A detailed assessment helps determine which communication difficulties are present.

How Is Dysarthria Assessed?

A speech-language pathologist (SLP) may assess:

• Speech intelligibility

• Voice quality

• Loudness and pitch

• Speech rate

• Articulation

• Resonance

• Breathing and respiratory support

• Prosody and speech rhythm

• Oral-motor and cranial nerve function

• Communication effectiveness

• Impact on everyday participation

Assessment may also examine language, cognition, swallowing, and other co-occurring communication difficulties when relevant.

The assessment should consider the individual’s communication needs, languages, cultural and linguistic background, daily environments, and personal goals .

How Can Speech Therapy Help Dysarthria?

Dysarthria speech therapy is individualized according to the person’s neurological condition, speech profile, and functional communication needs.

Therapy may focus on:

Speech Clarity

Improving articulation and strategies that make speech easier for listeners to understand.

Voice and Loudness

Working on appropriate vocal loudness, pitch, voice quality, and respiratory support.

Speech Rate

Developing strategies to manage excessively rapid or slow speech when this affects intelligibility.

Prosody

Supporting appropriate stress, rhythm, intonation, and naturalness of speech.

Communication Strategies

Teaching strategies that improve communication with familiar and unfamiliar listeners.

AAC and Alternative Communication

AAC may be introduced when speech is severely affected or becomes less reliable. Options may include communication boards, writing, letter boards, or speech-generating devices .

Restorative and Compensatory Approaches

Dysarthria therapy may include both restorative and compensatory approaches .

Restorative approaches aim to improve aspects of speech such as intelligibility, prosody, naturalness,

and efficiency.

Compensatory approaches focus on helping the individual communicate successfully despite persistent speech difficulties. This may involve communication strategies, environmental modifications, listener support, or AAC.

For progressive neurological conditions, therapy may also focus on maintaining communication abilities and preparing for changing communication needs .

When Should You See a Speech Therapist?

Consider an SLP assessment if an adult develops:

• New or worsening slurred speech

• Reduced speech clarity

• Difficulty being understood

• Significant changes in voice

• Unusually rapid or slow speech

• Reduced vocal loudness

• Speech changes following a stroke or brain injury

• Speech changes associated with a neurological condition

Sudden new speech difficulties can be a medical emergency , particularly when accompanied by facial weakness, arm or leg weakness, confusion, or other sudden neurological symptoms. Seek urgent medical attention in such situations.

Dysarthria Therapy at iSpeak Total Communication Clinics

At iSpeak Total Communication Clinics , dysarthria therapy is individualized according to the person’s speech profile, neurological condition, communication needs, and everyday goals .

Therapy may address speech intelligibility, articulation, voice, loudness, speech rate, prosody, communication strategies, and AAC when appropriate.

Our goal is to help adults communicate more clearly, efficiently, confidently, and independently across everyday situations.

Frequently Asked Questions

What is dysarthria?

Dysarthria is a motor speech disorder caused by neurological or neuromuscular difficulties affecting the movements required for speech.

Is dysarthria the same as slurred speech?

Slurred or unclear speech can be a symptom of dysarthria, but dysarthria can involve several speech characteristics, including changes in voice, articulation, rate, resonance, and prosody.

Can speech therapy improve dysarthria?

Speech therapy can work on speech production, intelligibility, communication strategies, and AAC based on the individual’s needs.

Can Parkinson’s disease cause dysarthria?

Yes. Dysarthria is common in Parkinson’s disease and may involve reduced loudness, limited prosody, and other changes in speech production.

Can dysarthria affect swallowing?

Dysarthria can occur alongside swallowing difficulties. When swallowing concerns are present, a separate swallowing assessment may also be required.

Can AAC help adults with dysarthria?

Yes. AAC can provide additional or alternative communication when speech is difficult to understand or becomes unreliable.

References

American Speech-Language-Hearing Association (ASHA). Dysarthria in Adults – Practice Portal.

ASHA Practce Portal – Dysarthria in Adults

Recommended citation:

American Speech-Language-Hearing Association. (n.d.). Dysarthria in adults [Practice Portal]. ASHA.

Copyright & Content Note

This article is original educational content prepared for iSpeak Total Communication Clinics . It summarizes information from ASHA’s clinical resource without reproducing ASHA’s copyrighted text, tables, images, or proprietary material. ASHA is credited as the clinical reference.

Disclaimer: This article is for general educational purposes and does not replace neurological or medical evaluation or an individualized speech-language assessment and treatment plan.