The 6 types of aphasia (causes, symptoms and characteristics)

This language disorder can be subdivided according to various clinical criteria.

The term language refers to the selection and ordering of words according to the rules of. When this language is produced orally or verbally, it requires a series of acquired skills, both vocal, auditory, visual and motor, in order to achieve proper communication.

However, when a person suffers some type of brain injury, aphasia may appear, which, strictly speaking, are disorders in the use of language, accompanied by a speech disorder.

However, there are different types of aphasia according to the injured brain areas, as well as according to the symptoms presented by the person.

• Recommended article: "Aphasia: the main language disorders".

What is aphasia? Definition and causes

Primarily, aphasia is the total or partial inability to use language.. The deficits associated with the different types of aphasia range from word finding problems to complete inability to speak.

The different aphasias also include problems with written language, listening comprehension, reading or dealing with numbers. In other cases, people present deficits in oral expression but keep their comprehension capacity intact. It is therefore necessary to detect in each patient what specific speech and language disorders he or she is subject to in order to develop an appropriate treatment.

The causes of aphasia are varied, but they all occur in circumstances of brain injury:

• Cranioencephalic trauma
• Tumors of the central nervous system
• Stroke (most frequent cause of aphasia)
• Degenerative diseases (Alzheimer's disease, Parkinson's disease, etc.)
• Localized or diffuse infections of the brain

Types of aphasia

The symptomatology of aphasia depends on both the location of the brain lesions and the compensatory reactions of the brain tissue that remains intact.

However, there are a number of common brain lesions that seem to group certain dysfunctions.

1. Broca's aphasia or major motor aphasia

In Broca's aphasia, deficits in the motor aspects of language and writing predominate, it is also accompanied by agrammatism and in many cases by language comprehension disorders. Occasionally, sensory problems on the right side and hemiparesis, which refers to a decrease in motor strength or partial paralysis affecting only one arm or one leg on the same side of the body, may appear.

This aphasia is the consequence of a large lesion involving the cortical and subcortical elements along the frontal and superior portion of the Sylvian fissure, including also the insula; but its name comes from the involvement of the inferior frontal gyrus or Broca's area in this disorder.

The most common causes of Broca's aphasia may be:

• Embolic occlusion of the superior division of the left middle cerebral artery.
• Frontal lobe abscess
• TumorHypertensive hemorrhage of the putamen
• Metastatic lesions
• Subdural hematoma

During the course of Broca's aphasia the patient may be in the acute or subacute phase.. During the acute phase, the patient is practically mute, unable to understand and unable to communicate, suffering a strong emotional impact, and as the patient progresses, comprehension begins to improve, while language and writing deficits persist. As the patient improves, he is able to speak aloud, but not without much slowness and effort.

Articulation and intonation are also affected, so that the language becomes mainly a speech of nouns and adjectives in which functional words such as articles, prepositions or conjunctions are omitted; becoming an agrammatical and telegraphic language.

After the acute and subacute phases, speech difficulties may persist. However, However, speech therapy can significantly improve the patient's condition..

Finally, due to the paralysis of the right hand, many patients cannot continue writing with the right hand; therefore, it requires re-education of writing with the left hand or taking advantage of new technologies to enable communication.

2. Transcortical motor aphasia

This aphasia manifests problems similar to those of Broca's aphasia. The main difference is that in transcortical motor aphasia there is a deficit in speech production, especially in speech initiation, spontaneity or spontaneity, or in the ability to communicate.The main difference is that in transcortical motor aphasia there is a deficit in speech production, especially in speech initiation, spontaneity or speech organization.

The articulatory aspect of speech does not usually present difficulties and language comprehension remains intact, as does the production of names of places and people.

The cause of Broca's aphasia-like problems may be that the genesis of the disorder is due to a small subcortical lesion above Broca's area. Currently, the involvement of a circuit from the supplementary motor area through the subcallosal fasciculus to the basal ganglia and Broca's area is suspected.

3. Wernicke's aphasia

Wernicke's aphasia is characterized by fluent speech but with a large number of substitutions and paraphasias, together with difficulties in comprehension.along with difficulties in comprehension.

During the subacute phase, language comprehension is often severely impaired in severe cases, reaching absolute incomprehension. However, speech is easy, clear and correctly articulated, and the rhythm contour is similar to that of normal speech. After these phases, auditory comprehension usually improves and paraphasia is reduced.

Compared to Broca's aphasia, in Wernicke's aphasia functional words are present, but there are semantic and grammatical confusions. In addition, in this type of aphasia the motor area is intact so there is no right-sided paralysis, so patients can write, although the content is disorganized and confused, as is the speech.

4. Conduction aphasia

In this syndrome it is repetition that is severely impaired.. Conduction aphasia is a fluent aphasia with near normal comprehension; but in severe cases, fluency is severely compromised due to problems in the production of isolated words; thus becoming sequential and short-sentence speech.

Traditionally, it has been believed that this aphasia appeared as a consequence of a lesion in the fibers connecting Broca's and Wernike's areas. But it has been found that there is also a relationship with lesions in the superior temporal gyrus and insula.

In addition to repetition difficulties, these patients have problems with word selection and phonemic sequencing within individual words.

5. Global aphasia

People with global aphasia suffer from severe speech disorders, including fluency and comprehension problems.communication is severely affected.

The most common cases are those in which patients only manage to say a few words and their language comprehension is also very limited, since they can neither read nor write.

The most frequent cause of global aphasia is a lesion that destroys a large part of the speech-related areas of the dominant hemisphere and is caused by obstruction of the left internal carotid artery or the middle cerebral artery.

6. Amnestic or anomic aphasia

Since anomia is a characteristic common to fluid aphasia, Wernicke's aphasia and conduction aphasia, we will only speak of anomical aphasia when the difficulty in finding words of common use appears in relatively isolated form.

Bibliographical references:

• Kuljic-Obradovic, D.C.. (2003). Subcortical aphasia: three different language disorder syndromes?. European Journal of Neurology. 10 (4): 445-8.