Understanding Apraxia and Dysarthria
Apraxia and dysarthria are two of the more common speech disorders found in adults. These disorders have a unique relationship with one another. They are both motor-speech disorders and each can be caused by injuries or other issues which result in neurological damage. These two disorders may have a lot in common; however they each have a unique set of symptoms and signs.
Apraxia Versus Dysarthria
Apraxia of speech is a disorder which can be present from birth or develop later in life. When adults develop apraxia later in life it is typically the result of a traumatic brain injury or stroke. Apraxia of speech (AOS) is also called verbal apraxia or acquired apraxia. Unlike dysarthria, apraxia is not caused by issues with the muscles involved in producing speech. Apraxia is caused by damage to the area of the brain responsible for planning and executing the muscular movements necessary to produce certain speech.
The muscles involved in producing speech are vocal cords, lips, tongue and, jaw. Someone living with AOS has muscles strong enough for proper speech and capable of performing the necessary movements for intelligible speech. The challenges with apraxia arise because the brain has difficulty executing the motor pattern or sending the proper signals to the muscles required to make the desired movements.
Dysarthria as a speech disorder typically characterized by weakness or other difficulties with muscles used to produce speech. With AOS difficulties stem from the brain sending the message to the muscles, dysarthria is a speech disorder dealing with the muscles directly. People with dysarthria often have tightness or weakness in certain muscles. Someone with dysarthria may have tightness or weakness on one side of their mouth. This could cause one side to look or work differently when resting or speaking.
Although dysarthria and apraxia are completely different disorders they can be caused by many of the same events or neurological issues. Dysarthria can be brought on as a result of traumatic brain injuries, strokes, and other issues that may cause paralysis or dysfunction of facial muscles.
The Symptoms of Apraxia
The observable symptoms of apraxia sound something like this. If someone living with AOS wants to say “make a cake” the speech that comes out may sound more like “ache a ache”. Although their muscles have the ability to work, their brain has difficulty with the coordination needed to have all of the muscles perform the exact right movements.
Symptoms of Apraxia Can Include:
Difficulty with Pronunciation-The word or words may not be spoken clearly or crisply.
Inconsistent Speech Difficulties-Someone with verbal apraxia may be able to make a particular sound or say a particular word one day, however the next day they have difficulty repeating the sound or saying the same word clearly.
Challenges with Rhythm and Inflection-Apraxia of speech may cause an individual to put stress or emphasis on the wrong syllable. They may also pause their speech at the wrong time or leave out certain sounds altogether.
Difficulty Finding the Right Word or Sound-We can all relate to the experience of not being able to think of the word we want to say. We search our brains, and we are able to come up with words that are similar in meaning or sound, but these words are not the words we are looking for. AOS can sometimes leave people searching for the proper word or sound. They may make many attempts at saying the word before the word in their mind is articulated correctly.
Symptoms of Dysarthria
Speech That Is Difficult to Understand-The speech may be mumbled or slurred.
Seemingly Winded Speech-Individuals with dysarthria may sound winded or as if they don’t have enough air to project their speech properly.Challenges with Muscle Control-Dysarthria may make it difficult for someone to move their jaw, lips or any of the other muscles involved in speech.
Changes in the Voice While Speaking-As somebody with dysarthria is speaking, their voice may fluctuate. They may sound horse or as if they are having trouble getting the words out.