Dysarthria is a problem with the muscles used for speech, while apraxia is a problem with the brain's ability to plan and organize movements needed for speech production. Despite the challenges of a motor speech planning disorder, or lack of motor speech function, children can make considerable progress with the help of specialized speech therapy.
In this article we will discuss:
If your child is struggling to speak because of motor skills planning, or muscle tone problems, they have what's called a motor speech disorder. Motor speech - or motor skills - disorders involve the planning of speech, as in apraxia, or the muscle ability needed to create speech, as in dysarthria.
What is a motor speech disorder?
While many forms of speech disorders are "functional," there are two primary disorders that are physical. These motor speech disorders are also called motor skills disorders: apraxia and dysarthria of speech. Both conditions can occur in children and adults, and people with motor speech disorders can have both apraxia and dysarthria at the same time. Or can be even more complex, as they can also co-occur with other communication disorders, such as receptive language disorder or impairments in social interaction skills.
Motor speech disorders involve a disconnection between the brain and physical speech mechanisms. People with motor speech disorders have difficulty controlling or coordinating the muscles that are used for speaking. These muscles are located in the face, larynx and tongue.
Speech therapy can help with motor speech disorders.
Reasons behind motor speech disorders
Illnesses can cause motor skills disorders - both dysarthria and apraxia may be associated with a variety of conditions including:
Cerebral palsy
Muscular dystrophy
Multiple sclerosis
Parkinson's disease
Myasthenia gravis
Huntington's disease
Brain tumors
Traumatic brain injury
Dysarthria is muscle weakness
Dysarthria is a type of motor speech disorder that is caused by muscle weakness. Dysarthria most commonly follows after some sort of damage to the brain, such as stroke, resulting in the need for speech therapy. People with dysarthria often find it physically difficult to speak, and their speech may be difficult for others to understand. Dysarthria is typically associated with muscle weakness caused by brain damage. It may be mild or severe.
The type of dysarthria a person has depends on the type of neurologic damage.
Flaccid dysarthria is associated with muscle weakness. The person's speech may sound breathy or nasally. The volume and pitch of their speech often does not change, and they may have a tendency to speak in short phrases. Due to the muscle weakness involved in this type of dysarthria, the person is likely to tire quickly after speaking.
Spastic dysarthria involves muscles that are too tight. The person's voice might sound harsh, and they may be nasally as well. Speech may be slow or strained, and the person may speak at a low pitch that does not change much.
Apraxia is a motor planning disorder
Apraxia is also caused by brain damage but is different than dysarthria. To understand apraxia, you must first understand the connection between the brain and speech.
Whenever you speak, messages are transmitted from your brain to your mouth. These messages signal each muscle involved in speech formation, telling the muscles when and how to move in order to form specific sounds. When someone has apraxia, those messages are not clear.
There are two main types of apraxia:
Acquired apraxia involves the impairment or loss of existing speech skills.
Developmental apraxia, which is also known as childhood apraxia of speech is present at birth.
People with the motor skill disorder of apraxia may sometimes form words correctly and then later have difficulty forming those same words the right way. There is often no rhyme or reason to apraxia, however speech might sound slurred or robotic even when the correct speech sounds are made. There are different levels of severity, too. Some people with apraxia cannot speak it all; others have difficulty moving their tongue and/or lips to form specific sounds. A speech pathologist can help - like the program here at Better Speech.
What causes a motor speech disorder?
Motor speech disorders are caused when neurologic damage affects the mechanisms that allow a person to speak. It's very important to note here that motor speech disorders do not affect cognition, which is the ability to come up with thoughts to share with the world.
Motor speech disorders are specific in that they affect the ability of speech generating organs including the lips, tongue, and throat to work together.
According to the Mayo Clinic,
54% of people with motor speech disorders have dysarthria caused by a breakdown in communication between the brain and muscles associated with speech.
Another 25% of people with motor speech disorders also have aphasia, which is a language disorder that often goes hand in hand with motor speech disorders.
Cognitive-language disorders including amnesia, dementia, and traumatic brain injury make up another 16%.
A relatively small 4% of motor speech disorders involve apraxia caused by difficulty with programming and motor planning. This can lead to the wrong sounds or words coming out, or to speech that sounds flat and robotic.
The final 1% of people with motor speech disorders are also affected by other neurogenic speech issues including stuttering, mutism, and others.
Diagnosing motor speech disorders
Motor speech disorders may be diagnosed by a doctor or by a speech-language pathologist who can test speech and language to determine why the individual is having trouble speaking. During testing, the SLP will listen to the way you speak and watch the mouth, lips, and tongue as they form the sounds that make up speech.
The testing process covers individual words and sentences, as well as conversation. In addition, speech-language pathologists test the individual's ability to put their thoughts into words and understand what others are saying.
Diagnosing motor speech disorders in children
Childhood motor speech disorders are sometimes diagnosed between the ages of 18 months into years of age, although later diagnoses are common. Children with motor speech disorders might be able to form only a few different sounds or words, and they might have difficulty separating syllables or words. Many children with motor speech disorders have difficulty imitating words as well.
Also known as CAS, childhood apraxia of speech is a motor speech disorder in which a child's brain has difficulty directing or coordinating speech movement. This leads to inaccurate movements when speaking.
CAS occurs for different reasons. Sometimes it is the result of a brain condition or injury such as an infection or traumatic brain injury. Sometimes childhood apraxia of speech is associated with a metabolic condition or genetic disorder. CAS often occurs in children with galactosemia. Children with speech apraxia often do not have the same muscle weakness exhibited by adults; even so, the muscles do not perform normally.
How do you treat motor speech disorders?
The treatment for motor speech disorders varies depending on whether dysarthria or apraxia is involved. Individuals with dysarthria and apraxia may receive a variety of different treatments for their motor speech disorders, usually with the help of a speech pathologist.
Apraxia treatment focuses on improving sound sequencing and coordination. People with apraxia can also benefit from sensory treatments aimed at improving awareness of how it looks and feels to produce different sounds. Apraxia of speech treatment is more beneficial the earlier it begins.
CAS, Childhood Apraxia of Speech, can be treated with apraxia speech therapy. During childhood apraxia of speech treatment, the focus is on teaching the child's brain to plan for moving speech muscles in the jaw, lips, and tongue.
Dysarthria treatments focus on strengthening muscles used to produce speech. Dysarthria treatments might also involve exercises aimed at increasing vocal and respiratory support for the production of speech as well as exercises designed to make speech more precise. Some dysarthria treatments help people change their rate of speech or volume (i.e., ataxic dysarthria treatment).
If you are treated for dysarthria, you might focus on:
Slowing your rate of speech
Strengthening your mouth muscles
Increasing the amount of breath you use when you speak, which can help you speak louder
Making sounds clearly as you say different words
Moving the muscles that control your tongue and lips more
Using other forms of communication, also known as augmentative and alternative communication or AAC
Treating motor speech disorders in children involves speech therapy as well. A child with CAS typically works alongside a speech-language pathologist, learning and practicing the correct way to say different syllables, words, and phrases, as well as practicing movements that form accurate sounds and words.
In children and adults alike, treatment for motor speech disorders often focuses on speaking at a normal speed, using a normal rhythm that is easier for listeners to understand.
How to help people who have motor speech disorders
Because it can be difficult to understand people who have motor speech disorders, it is important to pay careful attention when they are speaking. Here are some additional tips for interacting with people who have dyspraxia and/or apraxia.
If possible, choose a quiet setting where you can hear what is being said.
Watch as the person is speaking. Having good lighting can help.
Do not pretend to understand what is being said if you don't understand. Let the person know if you're having difficulty understanding, so that they can make themselves clear.
If you understood part of what was being said, repeat the part you understood and ask for clarification on the part you didn't understand. This way, the person is not forced to repeat themselves completely.
When you still have trouble understanding, consider asking yes or no questions that can help clarify the person's message. You might also ask the person to clarify by writing or pointing. Some people with dysarthria are able to communicate using gestures or computers as well.
Find speech therapy for motor speech disorders near me!
Consistent therapy with a speech pathologist can make all the difference for people with motor speech disorders. It is often possible to re-learn speech skills after the brain has been damaged. In addition, children with CAS can often learn better speech and language skills, resulting in improved communication.
At Better Speech, we offer online speech therapy services convenient for you and tailored to your child's individual needs. Our services are affordable and effective - get Better Speech now.
Frequently Asked Questions on motor speech disorders
What are the most common motor speech disorders?
The most common motor speech disorders include dysarthria and apraxia of speech, both of them are associated with different symptoms that the individual presents and should be treated differently.
What are some causes of neurogenic motor speech disorders?
What are the symptoms of a motor speech disorder?
What are acquired motor speech disorders?
About the Author
Mikee Larrazabal
I am a Speech-Language Pathologist with 14 years of experience working with children and adults who have communication difficulties. I completed my Bachelor of Science degree in Health Science at Cebu Doctors' University and have been helping people overcome their communication challenges ever since.
I have worked with individuals of different ages, including toddlers, preschoolers, school-aged children, adults and seniors. I'm passionate about speech therapy and take great satisfaction in helping people overcome their communication challenges and improve their lives through better communication skills. In my spare time I like reading books, going hiking in nature and taking care of my dog Locas.
