Aphasia: classification

Aphasia: definition

Aphasia is the title of the chapter concerning language disorders, essentially referring to the articulation and understanding of words: it is an acquired disorder, that is to say consequent to a trauma related to the cerebral hemisphere that coordinates language. introductory we have analyzed the general picture of aphasia: in this discussion we will examine the various forms of aphasia.

General classification

The aphasic forms are many and are distinguished on the basis of the quality / frequency of the speech, and the resulting symptomatic characteristics.

FLUENT PHASIA

Sometimes, the fluent aphasias are so slight that the affected patient does not understand his language deficit: in fact, the intonation, rhythm, accent and duration of the sentences are almost normal. What characterizes fluent aphasia is the not entirely productive speech: the affected subjects, in fact, are able to carry out only about twenty words per minute. Moreover, often times, their words are devoid of complete meaning and lacking a link that connects one word to the other. In such situations, we speak of empty language.
In turn, fluent aphasias are classified into:

Conduction or repetition aphasia: although the aphasic subject tries to repeat words by imitation, he presents a serious difficulty in word repetition. Understanding, however, is not compromised.
Anomic aphasia (amnesia nominum or amnesic aphasia): inability to intentionally name an object. The aphasic patient, in this case, preserves an almost fluent and spontaneous language, as well as oral and written comprehension, which remains unchanged. In other words, the anomie appears suddenly, within a fluent and clear speech; probably, the cause refers to a lesion similar to that found in transcortical aphasia of the sensory type, but of a minor entity.
Wernicke's aphasia or receptive (or sensory) aphasia: the name derives from the cerebral area compromised by the lesion. In fact, damage to the Wernicke area generates possible disturbances in the production and understanding of language; the patient elaborates a particular linguistic code, artificial and full of neologisms, sometimes incomprehensible. The sufferer is unaware of his ailment.
Transcortical sensory aphasia: the repetition of words is only partially impaired. Patients tend to be almost talkative, speaking fluently, but lacking in meaning.

NON FLUENT PHASIA

As for non-fluent aphasias, most affected subjects are aware of their verbal deficit: in this regard, patients - afflicted and defeated by the disease - tend to give up and refuse to speak.

The words are enunciated slowly and individually (when possible), since the aphasic is not able to join several terms at the same time. The intonation and rhythm of the words are evidently anomalous and particularly slow. Articles, adverbs and pronouns, useful for linking and enriching sentences, are almost never used by the aphasic patient (of the non-fluent type).
Among the non-fluent aphasias stand out:

Dynamic aphasia: comprehension skills remain intact, although speech skills are drastically reduced.
Motor transcortical aphasia: affected patients find it hard to speak spontaneously; however, they are able to repeat words and to name objects - upon indication or help - and to read aloud. The ability to understand written and oral language is also kept intact. A possible correlation has been found between trans cortical motor aphasia and stuttering.
Mixed transcortical aphasia (language area isolation syndrome): characterized both by a marked alteration of linguistic expression and by a marked impairment of language comprehension. However, this form of aphasia does not hinder the ability to repeat or imitate words: the patient is unable to speak and express himself, but is fully aware of the disease.
Broca's aphasia or expressive aphasia: writing, reading and simple spontaneous language are severely compromised and altered. Speech is telegraphic and the patient shows serious problems in anagramming the words; the few sentences are often devoid of complete meaning and lacking articles, prepositions and adverbs. In any case, the understanding of words and concepts remains unaffected; consequently , patients with Broca's aphasia keep their intellectual abilities completely intact and are aware of their disorder.In this regard, often affected subjects tend to despair, cry and get depressed.
Most often, the disease is caused by severe damage to the pre-central areas of the brain.

GLOBAL PHASIA

In global (or mixed) aphasias, speech is not fluent at all, so much so that it literally suppresses words. In this type, even the comprehension of language is heavily impaired. Global aphasia is defined as a severe alteration of language. , since speech production, processing and understanding itself are affected. The left cerebral hemisphere is involved, an area in which both the Perisylvian cortex and neighboring structures in the brain are located: for these reasons, the global form of aphasia is the most severe, usually due to a severe lesion of the middle cerebral artery [taken from Netter's internal medicine, by Stephanie Engelhardt, Martin Kortenhaus]

OTHER CLASSIFICATION OF APHASIA (based on the ability to understand / produce words)

According to the ability to understand language, aphasia can be further classified into:

Receptor aphasia: the patient's language is fluent and he is able to replace words with others. Auditory understanding is more problematic.
Receptive aphasia: the aphasic subject has a better expressive capacity than the understanding one. In such situations, the aphasic patient shows a significant inability to understand written and spoken language.
Expressive or modifying aphasia: the difficulty in articulating words or phrases is very marked, often associated with the inability of the subject to gesticulate.

In any case, in general, aphasia is neither completely receptive nor completely expressive, as it is often characterized by both disorders [www.msd-italia.it]