The field of medicine is known to be loaded with complicated and uncommon terms, and the field of speech therapy is no exception. There are times when speech therapists have to inform parents that their child has "dysarthria". What does this mean exactly?
Essentially, dysarthria is a speech disorder resulting from neurological injury.
The ability to communicate ideas through speech is a distinctive characteristic of the human being. The process by which humans voice sounds is in itself extremely complex. Each sound produced involves the integrity, participation and coordination of several anatomical structures and mechanisms, such as the tongue, lips, soft palate, respiration, proprioception, etc. The production of a sound is attributable to a variety of muscle groups that activate and release in a determined order at a strength, rate and duration level that will differ for each sound. Synergy at the neuromuscular level is therefore essential to speech. Scientists believe that producing fourteen sounds in a given second involves about one hundred muscles (Darley, Aronson, Brown 1975). This is all controlled by the central and peripheral nervous system.
The nervous system is somewhat similar to your home’s main electrical box. Imagine if the electrical wiring of your box were faulty. Upon turning on a lamp, you would likely experience some unusual events, such as fluctuating brightness, flickers or flashes, and short-term disruptions. Whatever the cause of injury to the central or peripheral nervous system may be (congenital paralysis, stroke, degenerative diseases), it can bring about neuromuscular dysfunction when executing the motor operations essential to speech, affecting rate, strength, range, spatial and timing precision. This is what is called dysarthria. One or several characteristics of speech may be affected: voice (intensity, quality), resonance (nasal timbre or no nasal timbre), articulation (precision) or prosody. Intelligibility may likely be decreased. Generally speaking, the more severe the injury, the greater the number of components will be altered and the more intelligibility will be less likely.
The work of a speech therapist focuses on maximizing speech efficiency while preserving its natural aspects as much as possible. Depending upon the severity, speech therapists may work on developing improved motor control, teach compensatory skills or recommend augmentative and alternative communications systems.