The 6 Types Of Aphasia (causes, Symptoms And Characteristics)
The term language refers to the selection and arrangement of words according to the rules When this language is produced orally or verbally, a series of acquired skills are needed, both at a vocal, auditory, visual and motor level; in order to achieve correct communication.
However, when a person suffers some type of brain injury, aphasias may appear, which, strictly speaking, are disorders in the use of language, accompanied by a speech disorder.
However, there are different types of aphasias depending on the brain areas injured; as well as depending on what symptoms the person presents.
Mainly, aphasia is the total or partial inability to use language Deficits related to different types of aphasia range from word-finding problems to complete inability to speak.
Likewise, the different aphasias also include problems in written language, oral comprehension, reading or having to operate with numbers. In other cases, people have deficits in oral expression but retain their comprehension ability intact. That is why it is necessary to detect in each patient what specific speech and language alterations they are subject to in order to develop an adapted treatment.
The causes of aphasia are varied, but they all occur in circumstances of brain injury:
Types of aphasia
The symptoms of aphasia depend both on the location of the brain lesions and on the compensatory reactions of the brain tissue that remains intact.
However, there are a series of common brain lesions that seem to group together 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, language comprehension disorders. Sometimes, sensory problems may appear on the right side and hemiparesis, which refers to a decrease in motor strength or partial paralysis affecting a single arm or leg on the same side of the body.
This aphasia is the consequence of a large lesion that includes the cortical and subcortical elements along the frontal and superior portion of the Sylvian fissure, also including the insula; but its name comes from the involvement that the inferior frontal gyrus or Broca’s area has in this disorder.
The most common causes of Broca’s aphasia may be:
During the evolution of Broca’s aphasia, the patient may be in the acute or subacute phase While the acute phase occurs, the patient is practically mute, cannot understand and is not able to communicate; also suffering a strong emotional impact. As the patient progresses, comprehension begins to improve, while deficits in language and writing persist. As he improves, he is able to speak out loud, not without much slowness and effort.
Articulation and intonation are also affected, so that the language becomes mainly a speech of names and adjectives in which functional words such as articles, prepositions or conjunctions are omitted; becoming an ungrammatical and telegraphic language.
After the acute and subacute phases, speech difficulties may persist. However, A therapy that works on language can significantly improve the patient’s condition
Finally, due to paralysis of the right hand, many patients cannot continue writing with it; 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 when initiating a speech in its spontaneity or in its organization.
The articulatory aspect of speech usually does not present difficulties and language comprehension remains intact, as does the production of names of places and people.
The cause of problems similar to those of Broca’s aphasia may be due to the fact that the disorder is caused by 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 along with difficulties in understanding.
During the subacute phase, language comprehension is usually very impaired in severe cases, reaching absolute incomprehension. However, the speech is easy, clear, and correctly articulated, and the rhythm contour is similar to that of normal speech. After these phases, listening comprehension usually improves and paraphasia is reduced.
If compared to Broca’s aphasia, in Wernicke’s aphasia functional words are present, but there are semantic and grammatical confusions. Furthermore, in this type of aphasia the motor area is intact so there is no paralysis on the right side, so patients can write, even though the content is disorganized and confusing, just like speech.
In this syndrome what is seriously affected is the repetition Conduction aphasia is a fluent aphasia with near-normal understanding; but in which, in severe cases, fluency is severely compromised due to problems in isolated word production; thus becoming a sequential speech and short sentences.
Traditionally, it has been believed that this aphasia appeared as a result of a lesion in the fibers that connect Broca’s and Wernike’s areas. But it has been discovered that there is also a relationship with lesions in the superior temporal gyrus and insula.
In addition to repetition difficulties, these patients have problems selecting words and phonemic sequencing within individual words.
5. Global aphasia
People with global aphasia suffer from severe speech disorders, including fluency and comprehension problems ; so communication is very strictly affected.
The most common cases are those in which patients can only say a few words and their understanding of language is also very limited, since they cannot read or write either.
The most common 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 common characteristic of fluent aphasia, Wernicke’s aphasia, and conduction aphasia, we will only talk about anomic aphasia. when the difficulty of finding commonly used words appears in a relatively isolated way
