The differences between Broca's aphasia and Wernicke's aphasia

Aphasia consists of a loss of the ability to express and/or receive language due to brain injury or damage. There are different types of aphasia that affect, to a greater or lesser extent, different abilities related to production and comprehension of speech, reading and writing, based on the areas of the brain that are seen affected.

In this article we will talk about the differences between Broca's aphasia and Wernicke's aphasia, and we will see what are the characteristics and symptoms of it.

• Related article: "The 6 types of aphasia (causes, symptoms and characteristics)"

Broca's aphasia: definition, characteristics and symptoms

Broca's aphasia or expressive, motor or non-fluent aphasia, named after the French anatomist Paul Broca, who contributed to the study and understanding of the origins of this aphasia, is a language disorder caused by a lesion in the third frontal gyrus of the left hemisphere, known as Brodmann's area 44 or area of Drill.

Broca's area is a region of the brain related to the production and expression of language, as well as the programming of verbal behaviors; that is, it is in charge of planning the necessary movements of the mouth and face to pronounce and articulate words. It is also involved in the morphosyntactic management of language and in the selection and discrimination of appropriate sounds (inhibiting irrelevant stimuli or sounds).

People with this disorder have great difficulty articulating and verbalizing words and expressions, with a great impediment to produce grammatically complex sentences (called agrammatism); In short, they are not able to form meaningful sentences (p. eg say “book child” instead of “the child is reading a book”).

In addition, speech becomes unproductive and not fluent, with little verbal content; In addition, the patient tends to make mistakes and use repetitions and fillers when speaking. Reading and writing problems also become evident, as well as difficulties repeat sentences and pronounce single words or short phrases (the patient invests a great effort to it).

Broca's area is connected, via the arcuate fasciculus, with another region of the brain involved in language reception, called Wernicke's area. This region is related to another type of aphasia that bears his name: Wernicke's aphasia, which we will discuss below.

Wernicke's aphasia: definition, characteristics and symptoms

Wernicke's aphasia, sensory aphasia or receptive aphasia, is named after the German neurologist Carl Wernicke, who described this aphasia and investigated its differences with respect to motor or Broca's aphasia, is a language disorder produced by a lesion in the posterior third of the superior temporal gyrus, known as Brodmann area 22 or area of Wernicke.

Wernicke's area is a region of the brain responsible for understanding and receiving language. (Oral and written). It covers the posterior area of ​​the left temporal lobe. This region is activated when we pronounce words and when we hear them, and when we plan a speech. The main function of this brain area is to identify, process and interpret phonetic sequences and the meaning of sounds.

The degree of involvement and clinical manifestations caused by Wernicke's aphasia are variable. Some people may develop a total inability to understand spoken or written speech, while others may retain the ability to understand a conversation or sentences loose.

The main characteristics of this neurological disorder are:

• Inability to understand language, in all its variants, even words or short phrases.
• Fatigue to follow a conversation when it goes on and difficulty following the thread, especially if there are distractors (environmental noise, other conversations, etc.)
• Production of incoherent language, with phrases or words that do not exist or are irrelevant.
• Use of phonemic and semantic paraphasias; that is, replacing letters or syllables of a word with others and substituting one term for another that has a similar meaning, respectively.
• Literal interpretation of set phrases, ironies or expressions with a double meaning (p. eg "not mincing words" or "being in the clouds").
• Use of neologisms (new or invented words).
• Anomia: inability to recognize or remember certain words or concepts.
• Anosognosia: the person does not perceive that he has a language comprehension deficit.
• Verbiage and jargon: excessive increase in spontaneous language and substitution of words for unintelligible ones, respectively.
• Difficulties repeating and naming words, and literacy problems.

Differences between Broca's aphasia and Wernicke's aphasia

Both Broca's and Wernicke's aphasia involve an alteration of language due to lesions in various areas of the brain; however, the differences between one disorder and another.

On the one hand, one of the basic differences has to do with the function and location of the brain regions that are affected in both aphasia. In Broca's, the person's ability to express language is affected when damage occurs in frontal areas, when Contrary to what happens in Wernicke's, in which the reception capacity of the same is affected, due to damage in areas of the temporal lobe.

On the other hand, in Wernicke's aphasia there is a severe deficit in speech comprehension and patients are unaware of it; on the contrary, in Broca's aphasia, language comprehension is practically unaffected and the patient has the feeling that he understands speech better than he knows how to express himself.

Another notable difference between Broca's and Wernicke's aphasia has to do with the fluency of speech.. Patients with Broca's aphasia are not able to speak fluently, however, people with Wernicke's aphasia do retain such verbal fluency. Likewise, the ability to repeat is impaired in both aphasias, but naming problems tend to occur more often in Broca's than in Wernicke's aphasia.

In relation to reading and writing, it should be noted that in both types of aphasias these processes are altered; however, in Wernicke's aphasia the graphics and certain automatisms are usually preserved.

Finally, with regard to age, it has been found that younger patients are often more prone to Broca's aphasia and the oldest Wernicke's aphasia, with a difference of 12 years on average between both types of aphasia.

Bibliographic references:

• Ardilla, A. (2005). The aphasias. University of Guadalajara, University Center for Social Sciences and Humanities.
• Vendrel, J. m. (2001). Aphasias: semiology and clinical types. Journal of Neurology, 32(10), 980-986.