Broca’s Aphasia: diagnosis, causes and rehabilitation
Aphasia is a neurological disorder that implies a loss of communicative skills, meaning you can lose expressive and comprehension of the language. Depending on the symptoms there are different types of aphasia. In this article, we will describe one type, Broca’s Aphasia, also known as production, expressive or motor aphasia. Broca’s aphasia causes a moderate or severe difficulty in communication, due to an alteration in the expression of language.
What is Broca’s Aphasia?
Broca’s aphasia affects the spoken language. The main characteristic of this aphasia is that the person is not able to express himself in a fluid way or form complete and articulate sentences, meanwhile, the comprehension is relatively preserved.
The language is divided into four components:
- Phonological system: regulates that an acoustic signal, organized in syllables and words, can be interpreted in the brain.
- Morphological system: it provides internal structure to words, using appropriate morphological combinations.
- Syntactic system: ensures that the combination of words are correct so that sentences and speech are coherent
- Semantic or lexical system: it is a set of ideas or internal mental representations with meaning.
Aphasias are usually classified and defined according to the location of the brain lesion. Broca’s aphasia is an injury in Broca’s Area. The Broca’s area is located in the left frontal lobe of the brain and it is considered the center of expressive language. It is responsible for several language components: phoneme order in words, word organization in sentences (syntax), semantic integration, and motor planning of language.
Broca’s Aphasia: Diagnosis
To carry out Broca’s aphasia diagnosis, we need to use neuropsychology and its evaluation instruments and tests. When performing any neuropsychological evaluation, and specifically the one aimed at assessing Broca’s aphasia, it is important to take into account two criteria that can influence oral communication:
- The level of education: the evaluation has to take into account the person’s previous education level.
- Cause and extension of the injury: the patient may present cognitive deficits associated with a more diffused lesion or specific lesions
A Broca’s aphasia diagnosis is based on the exploration of different language areas. All aphasias are assessed depending on the area of the brain affected. Recently, the treatment is focused on the symptoms and the classification of a type of aphasia is secondary. The exploration areas are as follows:
Spontaneous Speech in Broca’s aphasia
Spontaneous Speech is the ability to initiate and maintain speech. The assessment of spontaneous speech focuses on verbal fluency. The verbal fluency is a continuum, within which two conditions can be highlighted:
- Non-fluent speech: consists in difficulty broadcasting language, the aphasic patient can utter short sentences but with a lot of articulatory effort and fatigue. Dysprosody (irregularities in rhythm, tone, and inflections in the voice) and grammatical mistakes (alterations in the construction of syntactic structures) starts to be common in his speech.
- Fluid or hyper-fluent speech: it is normal or superior language production (more than 200 words per minute), accompanied by normal prosody and articulation. The alterations, in this case, are located in speech content and are known as paraphasias. They can be semantic (the word used is wrong and belongs to the same category as the one that should be used), and phonological (phonetic errors such as changing syllables or letters within a word).
In the case of Broca’s aphasia, spontaneous speech is considered non-fluid.
Comprehension in Broca’s aphasia
This skill is complicated to evaluate since the lack of response or incorrect answers can be due to aspects like the difficulty in the production of the language and not to lack of understanding. For this reason, tests are used, so language production is not necessary. The criteria used would be altered comprehension or preserved comprehension. The patients with Broca’s aphasia present the latter.
Repetition in Broca’s aphasia
It consists in the ability to decode auditory information, find the corresponding phonological code and reproduce it through the articulatory process. If any of these aspects is altered, the repetition will be affected. Through repetition of letters, words, and phrases, we can observe if there are difficulties in repetition or if it is preserved.
Naming in Broca’s aphasia
It is the capacity to name, that is to say, access lexical information to locate a specific linguistic element. For patients with Broca’s aphasia, this aspect is remarkably difficult and it is known as anomia (lack of vocabulary).
Automatic Sequences in Broca’s aphasia
Automatic sequences are sequences that have been learned and relearned such as numbers, months of the year, etc. Also it can be emotional and automatic language such as expressions. This type of language can be preserved in most aphasias, even severe ones.
Symptoms of Broca’s aphasia
Previously we have described the different areas to take into account when evaluating an aphasia. Here is a list of specific symptoms that will allow us to detect Broca’s aphasia:
- Lack of verbal fluency: slowness and fatigue in expression, including in speech with a reduced number of words.
- Anomia: difficulty in evoking the names of things
- Agrammatism: a tendency to form sentences without the correct inflectional structure
- Difficulties in repetition: they understand what you tell them but they are not able to repeat it.
- Awareness deficit: Just as in other aphasias the person is not aware of their mistakes and maintains the speech as if it were coherent. However, people with Broca’s aphasia do realize their mistakes due to the effort that speaking entails.
In addition to these symptoms, Broca’s aphasia may involve other associated neurological symptoms:
- Orofacial apraxia: inability to carry out coordinated movements in the face and mouth, without it being a physical cause.
- Hemiparesis: weakness in one entire side of the body.
- Hemiplegia: complete paralysis of half of the body.
- Alteration in reading and writing skills
Causes of Broca’s aphasia
Broca’s aphasia develops most commonly after suffering a stroke (ischemia or cerebral hemorrhage) in the left hemisphere (which is considered dominant for language). Broca’s Aphasia may also develop after a traumatic brain injury (TBI) or the presence of a brain tumor.
On the other hand, symptoms associated with Broca’s aphasia are observed in some neurodegenerative diseases:
- Non-fluid primary progressive aphasia: this is a progressive deterioration of language. At the beginning of its evolution, a person with non-fluid APP has no other signs of dementia. It stands out for the lack of fluency and the presence of agrammatism and anomia.
- Alzheimer’s disease: In addition to the typical symptoms of cognitive impairment caused by this disease (deficit in memory and attention, disorientation, etc.), there can also be a reduced spontaneous speech and anomia.
- Parkinson’s disease: There is a decrease in verbal fluency, poor syntactic complexity and, occasionally, grammatical changes.
Rehabilitation of Broca’s aphasia
Rehabilitation or skill recovery in Broca’s aphasia will depend on the initial severity of the symptoms. In the initial phase of cognitive disorders, some spontaneous recovery and reorganization of brain areas may happen that way the deficits are compensated. From that moment, the rehabilitation process begins, which is marked by the following objectives:
- Improve oral and written language skills
- Help their participation in daily communication
- Achieve effective communication, even if it is a simplified language style
- Improve patient’s quality of life
Rehabilitation in Broca’s aphasia is the main task of the speech therapist, although it is true that the neuropsychologist also plays a fundamental role in this process. The neuropsychologist together with the work done by the speech therapist then trains the person’s cognitive areas that can be affected (memory, attention and executive functions). Comprehension and repetition recover faster than naming and fluency. Depending on the linguistic deficits, a specific intervention plan is elaborated, which includes tasks such as:
- Basic neuropsychological stimulation (memory, attention, executive functions, reasoning, calculation, etc.)
- Naming activities to improve anomia, using phonological keys (first letter of the word, for example) and semantics (category to which the searched word belongs to)
- Training in sentence construction.
- Increase the size of expressions. Start with one item and increase to two, three, etc.
These are just examples of the work that can be done to restore cognitive abilities in people with aphasia. What is important is not to classify aphasia within a category, such as Broca’s aphasia, but rather to detect weaker abilities and work with them by relying on those that are preserved.
This article is originally in Spanish written by Natalia Pasquín.