What is apraxia of speech?
Apraxia of speech, also known as verbal apraxia,
dyspraxia, developmental apraxia, or childhood apraxia, is a speech disorder in
which an individual has trouble commanding the brain to say what he or she
wants to say correctly. Thus, it is a
motor command problem and not a problem related to weakness or paralysis of the
speech muscles (the muscles of the face, tongue, and lips). The severity of
apraxia of speech can range from mild where speech is intelligible but awkward
or struggled, to severe in which the individual is nonverbal or uses only a few
one syllable words.
What are the types and causes of apraxia?
There are two main types of speech apraxia: acquired apraxia
of speech and developmental apraxia of speech. Acquired apraxia of speech can
affect a person at any age due to brain damage such as a stroke. Acquired
apraxia of speech may occur together with speech muscle weakness (dysarthria),
or developmental problems such as autism or language delay. Developmental
apraxia of speech (DAS) is a childhood disorder and is present from birth. There
appears to be a higher incidence in boys than girls. DAS is different from a speech
delay, in which a child’s speech is developing in a typical manner, but at a slower
than normal rate.
The cause or causes of DAS are not yet known. Some
researchers believe it is related to a child’s overall language development.
Others believe it is a neurological disorder affecting the brain’s muscle
command system. To date, no studies have found evidence of specific brain
lesions, or differences in brain formation in children with DAS. Children with
DAS often have a family history of communication problems or learning
disabilities. Thus, recent research findings suggest that genetics may play a
role in the cause of the disorder.
What are the symptoms?
- Difficulty putting sounds
and syllables together in the correct order
- Longer words are usually
harder to say than shorter words
- Tendency to make
inconsistent mistakes when speaking
- Groping for the right
sound or word, but then have trouble repeating it
- Altered rhythm, stress,
and inflection of speech (prosody)
- Ability to understand
language is much better than the ability to express language
How is it treated?
Speech-language pathologists use various methods to treat
apraxia, and no single method has been proven to be the most effective. Therapy
is designed individually to treat other speech or language problems that may co-exist
with their apraxia. Each person responds differently to therapy, and some
people will progress at different rates than others. The treatment of apraxia
usually requires frequent and intensive one-on-one therapy consisting of, but
not limited to, much “drill” practice. Using music or rhythm is one strategy
that is often effective in facilitating speech production. Speech pathologists
call this “Melodic Intonation Therapy”. For this reason, music therapy has
become a popular supplement to formal speech therapy. Parent and caregiver
involvement is also a key component of success.
In severe cases, training to use alternative means to
communicate must be incorporated into their speech program, such as sign
language, a notebook with pictures, or an electronic communication device.