Wernicke's Aphasia


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WERNICKE’S APHASIA

(receptive aphasia, fluent aphasia, sensory aphasia):

 

Wernicke's area is an area of the brain, located in the temporal lobe on the posterior portion of the superior temporal gyrus, that is associated with the ability to understand and produce meaningful speech; damage to this area will cause Wernicke's aphasia

If Wernicke’s area is damaged in the non-dominant hemisphere, the syndrome resulting will be sensory dysprosody - the lack of ability to perceive the pitch, rhythm, and emotional tone of speech.


Characteristics

ü     Speech, while fluent, is semantically inappropriate with incorrect language content. This may vary from the insertion of a few incorrect or nonexistent words to a profuse outpouring of jargon. The form of the patient's speech may sound normal, however, the content is long, grammatically well formed utterances that contain almost no meaning

ü     Grammar, syntax, rate, intonation and stress are normal.

ü     Multiple Paraphasias are common.

§         Literal Phonological paraphasia – More than half of the spoken words said correctly.  Errors consist of mispronunciation, syllables out of sequence, etc.  (e.g. "I slipped on the lice (ice) and broke my arm.")

§         Verbal Semantic paraphasia - The substituted word is related to the intended word. (e.g. "I spent the whole day working on the television… I mean computer.")

§         Remote Semantic paraphasia - The substituted word is not related to the intended word. (e.g. "You forgot your lamp… I mean umbrella.")

§        Neologistic paraphasia - More severe mispronunciation, in which less than half the word is said correctly, if at all.

ü     Auditory comprehension and retention is poor.  The patient may repeat the examiner's words without understanding them.

ü     The major impairment is semantic. The speech of Wernicke's patients is sometime called cocktail hour speech.

ü     Comprehension and expression tend to be equally impaired.

ü     Wernicke's patients can process the main point in conversations but miss the specific details.

ü     Articulation is normal,

ü     Melodic Line is unaffected

ü     Short term memory recall is typically poor

ü     Word retrieval impairment is common.

ü     Confrontational naming is typically impaired.

ü     Alexia with agraphia may be present.

ü     Press of Speech phenomenon is common: Patients may speak very rapidly, interrupting others. It may seem as though the patient is striving for a sense of closure or a sense that (s)he has actually communicated what (s)he intended to say.

ü     The ability to understand and repeat songs is usually unaffected, as these are processed by the opposite hemisphere. "Melodic intonation therapy" can help stimulate the ability to speak with a normal rhythm and tone and recall information that is stored in a musical or rhythmic form.  

ü     Patients also generally have no trouble purposefully reciting anything they have memorized. The ability to utter profanity is also left unaffected; however the patient typically has no control over it, and may not even understand their own profanity.

Patients who recover from Wernicke’s aphasia report that, while aphasic, they found the speech of others to be unintelligible and, despite being cognizant of that fact that they were speaking, they could neither stop themselves nor understand their own words


LURIA'S THEORY ON WERNICKE'S APHASIA

Luria proposed that this type of aphasia has three characteristics.

  • 1) A deficit in the categorization of sounds. In order to hear and understand what is said, one must be able to recognize the different sounds of spoken language. For example, hearing the difference between bad and bed is easy for native English speakers. The Dutch language however, makes no difference between these vowels, and therefore the Dutch have difficulties hearing the difference between them. This problem is exactly what patients with Wernicke’s aphasia have in their own language: they can't isolate significant sound characteristics and classify them into known meaningful systems.
  • 2) A defect in speech. A patient with Wernicke's aphasia can and may speak a great deal, but he or she confuses sound characteristics, producing “word salad”: intelligible words that appear to be strung together randomly.
  • 3) An impairment in writing. A person who cannot discern sounds cannot be expected to write.

 

 

 

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