Aphasia is 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 the production and comprehension of speech, reading and writing, depending on the areas of the brain that are affected.
In this article we will discuss the differences between Broca’s aphasia and Wernicke’s aphasia , and see what their characteristics and symptoms are.
Broca’s aphasia: definition, characteristics and symptoms
Broca’s aphasia or expressive aphasia, motor or non-fluid, 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 Broca’s area.
The 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 major impediment to producing grammatically complex sentences (called agrammatism); in short, they are unable to form meaningful sentences (e.g., saying “book child” instead of “child is reading a book”).
Likewise, speech becomes unproductive and not very fluent , with little verbal content; in addition, the patient tends to make mistakes and to use repetitions and crutches when speaking. Reading and writing problems also become evident, as well as difficulties in repeating sentences and pronouncing single words or short phrases (the patient invests a great deal of effort in this).
Broca’s area is connected, through the arched fascicle, to another region of the brain involved in language reception, called the Wernicke 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 from Broca’s or motor aphasia, a language disorder produced by a lesion in the posterior third of the upper temporal gyrus, known as Brodmann’s area 22 or Wernicke’s area.
The Wernicke area is a region of the brain in charge of understanding and receiving language (oral and written). It covers the posterior area of the left temporal lobe. This region is activated when we speak words and when we listen to 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 affectation and the 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 individual sentences.
The main characteristics of this neurological disorder are
- Inability to understand language, in all its variants, even words or short sentences.
- Fatigue in following a conversation when it is long and difficulty in following the thread, especially if there are distractions (ambient noise, other conversations, etc.)
- Production of incoherent language, with phrases or words that do not exist or are irrelevant
- Use of phonemic and semantic paraphernalia; that is, replacing letters or syllables of a word with other words and substituting a term with another one having a similar meaning, respectively.
- Literal interpretation of set phrases, ironies or expressions with a double meaning (e.g. “not having hair on your tongue” or “being in the clouds”).
- Use of neologisms (new or invented words)
- Anomie: inability to recognize or remember certain words or concepts.
- Anosognosia: the person does not perceive that he or she has a deficit in understanding language.
- Verbiage and slang: excessive increase of spontaneous language and substitution of words by unintelligible ones, respectively.
- Difficulties in repeating and naming words, and reading and writing problems.
Differences between Broca’s aphasia and Wernicke’s aphasia
Both Broca’s aphasia and Wernicke’s aphasia involve a disruption of language by injury to various areas of the brain ; however, the differences between the two disorders.
On the one hand, one of the basic differences has to do with the function and location of the regions of the brain that are affected in both aphasia . In Broca’s, the person’s ability to express language is affected by damage to frontal areas, unlike Wernicke’s, where the ability to receive language is affected by damage to areas of the temporal lobe.
On the other hand, in Wernicke’s aphasia there is a severe deficit in speech understanding and patients are not aware of it; in contrast, in Broca’s aphasia, language understanding is practically unaffected and the patient has the feeling that he understands speech better than he can 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, yet people with Wernicke’s aphasia do retain their verbal fluency. Also, the ability to repeat is impaired in both aphasia, but naming problems tend to occur more in Broca’s aphasia than in Wernicke’s.
In relation to reading and writing, it should be noted that in both types of aphasia these processes are altered; however, in Wernicke’s aphasia the graphisms and certain automatisms are usually preserved.
Finally, with regard to age, it has been found that younger patients are usually more likely to suffer from Broca’s aphasia and older patients from Wernicke’s aphasia, with an average difference of 12 years between both types of aphasia.
- Ardila, A. (2005). Aphasias. University of Guadalajara, Centro Universitario de Ciencias Sociales y Humanidades.
- Vendrell, J. M. (2001). Aphasias: semiology and clinical types. Journal of Neurology, 32(10), 980-986.