Conduction aphasia has also been known as: kinesthetic or afferent motor aphasia, central aphasia, efferent conduction aphasia, suprasylvian conduction aphasia, or specifically as conduction aphasia. In conduction aphasia the language is fluent, but often in an unintelligible, jargon-like form, with a large number of paraphasias and neologisms. For this reason, it can be confused with Wernicke’s aphasia.
The difference is that there is no logorrhea and that the language may even seem not fluent due to the large number of pauses that the patient makes when not finding the words he is looking for. In the spontaneous language of the patient there is a constant tendency to self-correction. The phonemic approach is typical, in which the patient repeatedly tries to change the wrong phoneme.
When you hit the right one, you are able to identify it and make it noticeable. Another difference with Wernicke’s aphasia is that in driving aphasia the affected person perceives the mistakes they are making. The ability to understand is preserved and there is a good awareness of the deficit. Understanding can be similar to Broca’s aphasia and even better.
People with conduction aphasia fail to execute commands involving the body schema, especially if they involve a left / right orientation. Repetition is severely impaired and these patients cannot correctly repeat phrases, syllables, or words.
The denomination is also seriously compromised. The neologisms and paraphasias are semantic. Reading aloud is severely affected, but the patient can understand texts and written commands quite well. The writing is full of paragraphs.
Location of injury
Classically it had been assumed that this conduction aphasia occurred as a consequence of the involvement of the arcuate fasciculus. This nerve pathway joins the Broca and Wernicke areas. However, neuroimaging studies have shown that in reality this type of aphasia is usually due to temporal-parietal lesions that preserve the posterior region of the temporal cortex. It can also be caused by fronto-temporal lesions that preserve Broca’s and Wernicke’s areas.
Types of motor aphasias:
- Broca’s aphasia. It causes non-fluent speech, which is characterized by a slow pace, limited coherence, and perceptible difficulty in putting thoughts into words. In some cases, this form of motor aphasia severely limits an individual’s vocabulary to a few words or syllables. While understanding of plain language is generally maintained, the individual with Broca’s aphasia may have difficulty understanding complex or complicated sentence structures. This difficulty in understanding applies to both spoken and written sentences and phrases.
- Transcortical motor aphasia (TMA). It is characterized by difficulties in speech and understanding similar to that of Broca’s aphasia. Individuals with TMA, however, retain the ability to repeat phrases or word lists, while those with Broca’s aphasia tend not to. TMA is usually caused by a [stroke].
- Global aphasia. In some cases of severe brain injury, global aphasia can occur. Global aphasia is characterized by an almost complete loss of the ability to understand or produce written or spoken language. Other mental abilities, such as mathematical reasoning and non-linguistic social understanding, tend to remain intact in people with global aphasia, indicating that the “language centers” of the brain are distinct from other reasoning areas of the brain.
Treatment
Many options are available for the treatment of motor aphasia. A very popular form of treatment, called melodic intonation therapy, is based on the observation that people with aphasia avoiding the lines that speak of text in conversation are often able to sing the same words or phrases. The goal of therapy is to teach individuals with motor aphasia to understand and produce language based on their melodic qualities. The parts of the brain responsible for music and melody are, in essence, replaced by damaged language centers.