Conduction Aphasia

Having a robust Wernicke area, the patient is able to understand both the speech heard from ear, or the writing read. The patient can also express the things s/he would like to say as her/his Broca area is also robust. However, many literal paraphasia (jumbling of sounds within a word) may occur while speaking. That’s why, these patients are mistaken for Broca aphasia. The reason of occurrence of this type of aphasia is a problem present in the fibers extending from Wernicke to Broca.

Conduction Aphasia

Conduction Aphasia patients speak telegraphically; they have difficulty in saying more noun-words. They have literal paraphasia (jumbling of sounds within a word), which they put a great effort to correct. If they said “fwoler”, then they try to say “flower”. This is a fluent aphasia. The understanding is significantly protected.

Although the comprehension of the patient is good as s/he has a robust Wernicke area, this message cannot be conducted to the Broca area due to a lesion present in the fibers connecting this area to Broca, and in turn the patient cannot repeat a word s/he has just heard or understood. For example, a patient having a low level of conduction aphasia, to whom you show a picture giraffe and asked to tell what it is, may talk like this: “I know, I’m saying it right away. Gif, gif, no, it’s not, gir, gir, girf, no way, hold on, I’m going to tell you, gif, girf, garif, no, why can’t I just say it, but I know it, hold on, gifarre, no way, what am I saying!”

We can observe the following two difference between the literal paraphasic speeches of the Broca and conduction aphasias. Initially, while the Broca aphasias can cause literal paraphasia in all kinds of words, the conduction aphasias do this only in noun-words. Secondly, the Broca aphasia does the literal paraphasia (jumbling of sounds within a word), one may say “gifarre” and leave it here; however, a patient with conduction aphasia continues their literal paraphasic approaches to say the word correctly. S/he gets surprised at how s/he cannot say it. Moreover, while the Broca aphasia shows a “non-fluent” way of pronunciation, the conduction aphasias can say their words quite fluently, excluding the words they make literal paraphasia on.

They name what they see in a broken manner. While carrying out the naming examination, it can be observed that the patient easily finds the correct word without struggling and but tries to say it through literal paraphasic (jumbling of sounds within a word) approaches coming out of her/his mouth successively. That’s why, an inexperienced person may mistake a patient with conduction aphasia for a patient with non-fluent aphasia (Broca). However, as distinct from non-fluent aphasias, these patients do not have difficulties in the motor realization of putting the word out of their mouths; the articulation of syllables occurs at a normal pace.

Patients with conduction aphasia can read from within but not out loud. Although they understand this article easily when they read from within, they fail to do so when asked to read the same out loud; because despite the fact that the visual message is read and understood, it is not possible to say it out loud as this message cannot be conducted to the Broca area due to the lesion present in the fibers between the Wernicke and Broca. These patients can write, but in a broken manner. Sometimes the patient can write a word s/he somehow cannot say; then shows it to the person in front of her/him but cannot say it anyway.

Global Aphasia

It could be said that this is the worst type of aphasia as it turns into Broca or Wernicke in time. It mainly turns into Broca. The damages that occur in the Wide Left Perisylvian are its most basic causes, while the MCA itself is infarcted. Another cause is the right-sided strokes on arms and legs at equal degrees. They cannot say any word as they are deprived of uttering. They neither can understand, nor can they speak. Their abilities of understanding, repeating, reading, writing and naming what they see are completely deteriorated.

Prof. Dr. Kemal Arıkan