Transcript Document

FON 218: Neurolinguistics
APHASIA
Wanda Jakobsen
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What is Aphasia?
Aphasia is a loss of the ability to produce and/or comprehend language, caused by
damage to brain areas specialised for these functions. These areas are almost
always located in the left hemisphere and this is where the ability to produce and
comprehend language is found. However, in a very small number of people language
ability is found in the right hemisphere.
Most commonly it is seen in adults who have suffered a stroke, a brain tumor,
infection or head injury. The type of language disfunction depends on the location
and extent of the damaged brain tissue.
It is very rare in children.
Symptoms:
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Inability to comprehend language
Inability to pronounce
Inability to form words
Inability to name objects
Persistent repetiotions of phrases
Paraphasia (substitution of letters or words)
Agrammatism (inability to speak in a grammatically correct form)
Uncompleted sentences
Inability to write
Inability to read
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Classification of aphasia
BROCA’S APHASIA & WERNICKE’S APHASIA
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Broca’s aphasia
(Expressive aphasia)
It is caused by a damage to anterior regions of the brain including the left inferior
frontal region known as Broca’s area.
Sufferers of this form of aphasia exhibit the common problem of agrammatism. For
them speech is difficult to initiate, non fluent. Language is described as telegraphic
and reduced to disjointed words. Sentence construction is poor, omitting function
words and inflections.
Ex. Yes.. ah.. Monday…Dad and Peter H. and Dad…hospital…and Wednesday.. Wednesday, nine
o’clock.. and Thursday.. ten o’clock, ah doctors.. two doctors.. and ah.. teeth.. yah
Here the patient is trying to explain how he came to the hospital for dental surgery.
In extreme cases patients may be only able to produce a single word. The most
famous case of this was Broca’s patient Leborgne, nicknamed “Tan”, after the only
syllable he could say.
Comprehension:
Patients who recover say that they knew what they wanted to say but could not
express themselves.
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Wernicke’s aphasia
(Receptive aphasia)
It is caused by a damage to posterior part of the of the superior temporal gyrus of
the dominant hemisphere.
Individuals with Wernicke’s aphasia may speak in long sentences that have no
meaning, add unnecessary words, substitute a word for another and even create
neologisms.
Ex. I called my mother on the television and did not understand the door. It was too breakfast,
but they came from far to near. My mother is not too old for me to be young.
Comprehension:
Patients who recover from Wernicke’s aphasia report that, while aphasic, they
found the speech of others unintelligible and they could neither stop themselves
nor understand their own words.
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Anomic aphasia & Global aphasia
Anomic aphasia is the least severe form of aphasia. Patients have difficulty in
remembering and using the correct names for particular objects, people,
places, or events. The subject speaks fluently and grammatically, the only
deficit is trouble with word-finding.
Global aphasia is the result of a severe and extensive damage to the
language areas of the brain. Patients loose almost all language functions,
both comprehension and expression. They cannot speak or understand
speech, nor can they read or write.
Primary aphasia & Secondary aphasia
Primary aphasia is due to problems with language-processing mechanisms.
Secondary aphasia is the result of other problems, like memory impairments,
attention disorders or perceptual problems.
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Acquired Childhood Aphasia
Acquired childhood aphasia is a child’s partial or total loss of the ability to
understand words and use language because of a brain injury. Acquired means
that it occurs after the child has begun developing language skills.
One form of acquired childhood aphasia is called LKS, Landau-Kleffner
syndrome.
Aphasia can occur in children who have experienced head trauma, encephalitis, a
brain tumor, stroke, or other brain disorders.
Researchers have found no connection between aphasia and age and gender.
However LKS is usually seen in children between the age of 3 and 7.
Symptoms in children can begin with speech delays and progress to the loss of
communication skills. Symptoms can be temporary or permanent depending on
the damage.
LKS can be difficult to diagnose because its symptoms are similar to many other
neurological disorders, such as autism and mental retardation.
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Is there any treatment?
In some instances, an individual will completely recover from aphasia
without treatment.
In most cases language therapy should start as soon as possible and be
tailored to the individual needs of the patient.
Rehabilitation with a speech pathologist involves:
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Exercises in reading
Exercises in writing
Exercises in following directions
Repetitions of what they hear
Computer-aided therapy
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