Apraxia of speech: types, symptoms, causes and treatment.

A disorder that affects the ability to speak and communicate orally.

Apraxia of speech is an acquired disorder of neurological origin in which a person's ability to produce sounds and language in a manner that is in which the person's ability to produce sounds and language in a coherent and intelligible way is altered, due to the alteration of the rhythm, intonation or speed of speech.

In this article we will see what this disorder consists of, what are the main types of apraxia of speech and its symptoms, as well as the different treatments available.

What is apraxia of speech?

The term "apraxia" is today used to refer to impaired motor speech programming. It was the physician and anatomist Paul Broca who first referred to this concept in the mid-19th century.. This disorder is a consequence of damage to the left cerebral hemisphere.

Apraxia of speech is a neurological disorder related to language that causes alterations in articulation and prosody (elements of oral expression such as accent or intonation). Evidence suggests that this condition is the result of a lesion in the third frontal gyrus of the dominant hemisphere (in Broca's area) or Brodmann's area 44 and 45. It has also been suggested that the basal ganglia may have similar speech programming functions.

This type of lesions can be caused by trauma, tumors, degenerative diseases, and other neurological disorders, although the most common etiology is that the basal ganglia may have similar speech programming functions.The most common etiology is usually stroke. Usually the brain injury occurs in the parietal lobes or adjacent areas, with preservation of learned movement patterns.

Less frequently, apraxia of speech results from damage to other brain areas, such as the premotor cortex (located just in front of the motor cortex), other areas of the frontal lobe or the corpus callosum; diffuse involvement linked to degenerative dementias may also occur.

Types of apraxia of speech

There are two main types of apraxia of speech: acquired apraxia of speech and childhood apraxia of speech. Let's see what each of them consists of.

Acquired apraxia of speech

This type of apraxia of speech can occur at any age, although it usually affects adults. This specific type of apraxia occurs as a result of lesions in areas of the brain. as a result of lesions in areas of the brain that are involved in speech and results in loss or and results in loss or impairment of speaking skills. It may be the result of a stroke, head injury, tumor or any other disease affecting the brain.

In addition, this type of apraxia of speech may occur in conjunction with other disorders affecting the nervous system, such as dysarthriaFor example: dysarthria, a disorder characterized by difficulty articulating sounds and words, caused by paralysis or ataxia of the nerve centers that control the speech organs; or aphasia, a language disorder consisting of difficulty or inability to communicate through speech, writing or mimicry, due to brain damage.

Childhood apraxia of speech

This type of apraxia is present from birth. Infantile apraxia of speech is not the same disorder as delayed speech development, in which the child develops normal speech but at a slower rate. In apraxia, children have difficulty planning the movements necessary to produce speech.

Although the muscles involved in the speech process are not weak, they do not function as they should because there is an obvious difficulty in directing or coordinating the movements. because there is an obvious difficulty in directing or coordinating the movements. However, the causes of this disorder are not yet well understood, as studies and neuroimaging tests have not been able to find evidence of brain damage or differences in brain structure in these children.

It is common for children with apraxia of speech to have a family member with a history of a communication disorder or some type of learning disability. or some type of learning disability. For this reason, some researchers have suggested that genetic factors may play a significant role in the development of the disorder. It should also be noted that gender would be an equally significant variable, since this type of apraxia tends to affect boys more than girls.

Characteristic symptoms

There are a number of characteristic symptoms in people with apraxia of speech. Although may vary depending on age and the severity of the disorder and speech problems, the and speech problems, the most common are as follows:

The person makes trials and errors and then attempts to self-correct.

• There is articulatory inconsistency over repeated productions of the same utterance (the person does not manage to articulate the sounds well even if he/she tries several times).
• There are prosody errors (in accentuation, intonation and rhythm).
• Errors of incoherence in speech (for example, the person says a word well but then cannot repeat it).
• There is a distortion of sounds and difficulties in pronouncing words correctly (due to the inability to position the orofacial muscles properly).
• The person has difficulty initiating an utterance (hesitates when starting to articulate the first words).

Treatment

The goal of treatment for apraxia of speech is to enable the patient to communicate effectively.Therefore, the professional's goal is to restore, as far as possible, the patient's speech, that is, to make it functional, even if it is not possible to return the person to the levels of communication that existed before the onset of the disorder.

There is now a consensus that there are five categories of treatment for apraxia of speech: kinematic articulatory; rate and/or rhythm-based treatment; alternative and/or augmentative communication; intersystemic facilitation and reorganization; and other treatments.

Kinematic articulatory treatment focuses on treating articulation problems, putting the focus on the spatiotemporal aspects of speech production. Regarding rate and/or rhythm-based methods, their approach is based on treating the alteration that patients present in speech production times, helping them to control the rhythm in order to, in this way, recover temporal speech patterns.

As for alternative and augmentative communicationare two forms of intervention that seek to improve communication through the use of modalities other than the traditional use of speech. Some activities in this method involve the use of symbols, drawings and communication boards, computer programs, etc.

Finally, in relation to facilitation and intersystemic reorganization techniques, it should be noted that these methods involve the use of systems and modalities that are intact in the patient to facilitate the implementation of other modalities and systems that are altered; for example, through the use of gestures or graphic stimuli that facilitate speech, singing familiar melodies, etc., etc., etc.

Bibliographical references:

• R. González Victoriano and L. Toledo Rodríguez, "Apraxia of Speech: Evaluation and Treatment," 2015. [Online]. Available: http://repositorio.uchile.cl/handle/2250/134234
• Ygual-Fernández A, Cervera-mérida JF. Verbal dyspraxia: clinical features and speech therapy. Rev Neurol. 2005; 40: 121-26.