GLOBAL APHASIA: SYMPTOMS, CAUSES AND TREATMENT - NEUROPSYCHOLOGY - 2024

The global aphasia is mainly characterized by an inability to turn thoughts into language, as well as difficulty understanding verbalizations of others. This type of aphasia supposes serious deficiencies for the individual, since it presents both expressive and receptive language alterations. This supposes a generalized affectation of the communication, occupying anterior and posterior perisylvian areas.

This disorder appears to be relatively common, between 25 and 32% of those affected by aphasia in the acute phases of a stroke. However, after a year the percentage drops significantly.

Causes

The main cause of global aphasia is cerebrovascular accident (CVA), like other types of aphasia. In fact, in the acute phase of stroke it is estimated that between 20 and 30% of people have some type of aphasia. The percentage is higher the less time has passed after brain damage.

Usually, the left or dominant hemisphere is the one that is most related to language. Therefore, lesions in the left brain areas that produce and receive language are those associated with this pathology.

The damage covers Broca's and Wernicke's areas, necessary both to understand and express language, access words, use grammar, and construct sentences.

Global aphasia appears to be due to cerebrovascular accidents that extensively affect the middle cerebral artery of the left hemisphere. It ends up altering the entire perisylvian area of ​​said hemisphere, encompassing the inferoposterior region of the frontal lobe, the basal ganglia, the auditory cortex, the insula and posterior areas of the temporal lobe.

Less commonly, it can also occur due to hemorrhagic or ischemic subcortical lesions of the left hemisphere:, which affect the thalamus, basal ganglia, internal capsule, periventricular white matter and temporal isthmus (connections that come from other areas to the temporal cortex).

Symptoms

The main symptoms of global aphasia are:

Limited propositional speech

Propositional or voluntary speech is limited to a few simple words or phrases, which are sometimes repetitive or stereotyped. Kertesz in 1985 describes the case of a patient with global aphasia who only said the word “cigarette” repeatedly, even though he was asking for water. This author believes that it could have influenced that the patient was a tobacco addict.

Stereotypes

Stereotypies (repeated vocal emissions without any specific purpose) may appear that are not real words or do not have content; drawing attention to how well they pronounce them.

However, contrary to what may be believed, the type of stereotypy (whether it is real or not) does not indicate that the case is more serious or that there is a poor prognosis.

An example is seen in the case presented by Nieto, Barroso, Galtier and Correia (2012), in which the patient with global aphasia presents a stereotype consisting of always repeating “that you, that you, that you”.

Hemiplegia, hemiparesis, hemihypoesthesia and hemianopia

Normally, the lesion that produces aphasia also causes alterations in somatosensory and movement areas, which can lead to hemiplegia (when half of the body is paralyzed by lesions located in the opposite hemisphere), hemiparesis (the same but milder), hemihypoesthesia (lack of sensation in the middle of the body) and hemianopia (the person sees only half of their visual field).

Mutism

Almost immediately after injury, the patient may be completely mute. This means that it does not broadcast any verbal content. As time passes, he regains the ability to speak.

Apraxia

Apraxias may also appear, which are problems to perform movements that are not related to physical damage, but rather to the brain. They are mainly of the oro-facial or ideomotor type.

Verb Series Automation

Automated verb series such as days of the week, months, numbers or letters of the alphabet are usually kept (and they are pronounced fluently). It is believed that it may be due to the intact activity of the right hemisphere (which is normally preserved, since it seems that damage to the left hemisphere is what causes problems in language).

Other symptoms

- He speaks little and when he does, he does so with effort and lack of fluency. The way of speaking is known as "telegraphic speech."

- Lack of both oral and written comprehension, understanding only some words, verbs or expressions.

- Altered repetition of words and phrases.

- Reading and writing impaired.

- Failures in the naming of people, objects or animals.

- Global aphasia can be accompanied by other problems such as apraxia of speech, alexia, pure deafness for words, agraphy, or facial apraxia.

- Apathy or depression is common.

- The little communication they establish is thanks to simple automated expressions that are emitted with the correct intonation, such as “damn it!”.

- The ability to make gestures to communicate or use correct intonation is also related to the conservation of the right hemisphere.

- They have completely preserved the intellectual capacity that is not associated with linguistic aspects (National Aphasia Association, 2016).

- They are generally oriented, attentive and have socially appropriate behaviors (Brookshire, 2007).

- They can answer with monosyllables like "yes" or "no". They respond best if asked about personal experiences or family issues.

- They are able to recognize names of real objects or locations, just as they know when non-real words are being said to them or even detect a wrong word for that situation.

Types

It can be distinguished:

Classic global aphasia

It is being studied very recently and seems to be caused, among other things, by cerebral embolisms that cause non-contiguous damage in anterior and posterior perisylvian areas.

How does it evolve?

If we compare it with another type of aphasia, global aphasia has the worst prognosis. In the first few months, the symptoms improve dramatically. This is called spontaneous recovery, and it is much more noticeable if the damage is not very extensive.

Generally, the evolution of this type of aphasia is not very favorable, especially if the diagnosis is late. If diagnosed during the first week after injury, 15% of subjects within one year recover from aphasia.

These same authors indicated that 22% can be maintained with slight improvements, 35% progress to Broca's aphasia, an anomic aphasia (22%) or very rarely, to Wernicke's aphasia (7%).

In a study by Oliveira and Damasceno (2011) it was found that global aphasia could be a predictor of mortality after an acute stroke, indicating that this condition negatively affected the prognosis.

When it is of the classic type, it occurs together with hemiplegia or hemiparesis, hemihypoesthesia and hemianopsia. The severity and duration of these associated problems will affect the prognosis of aphasia, making it more severe and making recovery difficult.

On the other hand, Smania et al. (2010) wanted to observe the evolution of global aphasia in a patient in the long term (25 years). They found three important stages in recovery: one year after the stroke, where verbal comprehension and word repetition recovered; about 1 to 3 years later, the denomination and reading improved; and from 3 to 25 years, spontaneous speech appeared in addition to increasing performance in the tasks mentioned.

In spite of everything, properly treated patients with global aphasia show significant improvements in their communication skills and language tasks.

Evaluation

Global aphasia is evaluated in a similar way to other forms of aphasia, that is, with various tests that cover as much as possible aspects of language and cognitive abilities (to rule out other problems).

The most widely used to assess language skills in aphasia is the Boston Test for the diagnosis of aphasia. It is made up of subtests that measure expressive language fluency, listening comprehension, naming, reading ability, repetition, automatic speech (such as issuing automated sequences and reciting), and reading comprehension.

It is also used for the Western Batery Aphasia (WAB), which assesses both language and non-language skills. Among the former are speech, fluency, listening comprehension, repetition, reading and writing; while the non-linguistic ones examine drawing, calculus, praxis and visuospatial tasks. Also assesses praxis, memory and visuoperceptive functions.

Frontal functions can often be affected, which are those related to impulsivity, the ability to plan, categorize, and flexibility of cognitive strategies. They can be assessed with tests such as the Porteus Labyrinth, Wisconsin Card Sorting Test, or the Tower of Hanoi.

These tests can also be used to see whether or not rehabilitation has produced changes in the patient.

Treatment

There is no single treatment for global aphasia. The main objective will be to improve adaptation to the environment and quality of life to the maximum. For this, agreements must be reached through the multidisciplinary collaboration of speech therapists, neuropsychologists, physiotherapists and occupational therapists, in addition to the support of the family.

Rehabilitation must be designed for the abilities and personal and unique situation of each individual, that is, it must be personalized.

Group therapies

They can be helpful in patients with global aphasia, as their social skills are often intact. Thus, they perform simple activities or games that promote social communication.

Visual Action Therapy (VAT)

It is a program that enhances the use of symbolic gestures for communication and reduces apraxia. However, it does not improve verbal expression. For this reason, Ramsberger and Helm-Estabrooks in 1989 designed the orofacial TAV program, in which they introduced stimuli that involve facial and oral movements to perform gestures.

It consists of 3 levels: the first includes the manipulation of real objects, drawings of objects and action images, the second only uses action images and the third only the objects.

Educate caregivers and family

- Speech and language therapy to improve communication with other people and quality of life.

- The level of motivation and aspects of the personality influence recovery.

Important tips for treating aphasia

It is important to distinguish between language and intelligence, as many people may believe that speech difficulties are due to deficits in intellectual abilities.

This is not the case, it should be noted that there are completely preserved cognitive abilities, only that these people do not know how to express what they think. For example, they can have an independent life, move alone, retain opinions, and have a memory for faces just as before the problem.

Try to provide a means for people with aphasia to express what they want, avoiding frustration and isolation.

Techniques

Some techniques that the family can use to facilitate communication include: using closed questions (that can be answered with "yes" or "no"), paraphrasing the conversation, using simpler phrases, trying to reduce the duration of the conversation, use gestures to emphasize important content, say what to talk about before starting the conversation, etc.

It seems that it is easier to begin rehabilitation by talking at the beginning with a single interlocutor who understands this disorder and with whom the patient is comfortable. Little by little, as you improve, add more interlocutors until you end up conversing with small groups of people.

A quiet environment without distractions, noise, or other background conversations is best.

Better to deal with common and useful topics, which are used in daily life; or current events.

Supervised practice of conversations is useful, without tiring the affected person.

Other possible lines of communication can be created if it is very serious. The important thing is that this person can understand language and express it, even if they cannot speak or write.

References

1. Brookshire, RH (2007). Introduction to neurogenic communication disorders (Seventh edition.). St. Louis, Mo.: Mosby Elsevier.
2. Collins, M., (1991). Diagnosis and Treatment of Global Aphasia. San Diego, CA: Singular Publishing Group, Inc.
3. Global Aphasia. (sf). Retrieved on June 22, 2016, from the National Aphasia Association
4. Kertesz, A. (1985). Aphasia. In: Frederiks JAM, ed. Handbook of clinical neurology, vol 1. Clinical Neuropsychology. (pp. 287-331). Amsterdam: Elsevier.
5. Nieto Barco, A., Barroso Ribal, J., Galtier Hernández, I. and Correia Delgado, R. (2012). Chapter 12: global aphasia. In M. Arnedo Montoro, J. Bembibre Serrano and M. Triviño Mosquera (Ed.), Neuropsychology through clinical cases. (pp. 151-161). Madrid: Editorial Médica Panamericana.
6. Oliveira, FF & Damasceno, BP (2011). Global aphasia as a predictor of mortality in the acute phase of a first stroke. Archives of Neuro-Psychiatry, (2b), 277.
7. Smania, N., Gandolfi, M., Girardi, P., Fiaschi, A., Aglioti, S., & Girardi, F. (2010). How long is the recovery of global aphasia? twenty-five years of follow-up in a patient with left hemisphere stroke. Neurorehabilitation And Neural Repair, 24 (9), 871-875.
8. Steele, R., Aftonomos, L., & Koul, R. (2010). Outcome improvements in persons with chronic global aphasia following the use of a speech-generating device. Acta Neuropsychologica, 8 (4), 342-359
9. Types of Aphasia. (March 6, 2015).
10. Wapner, W., & Gardner, H. (1979). A note on patterns of comprehension and recovery in global aphasia. Journal of Speech and Hearing Research, 22, 765-772.
11. Western Aphasia Battery. (sf)