FON 218: Neurolinguistics

1. FON 218: Neurolinguistics APHASIA Wanda Jakobsen

2. 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: • 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

3. Classification of aphasia BROCA’S APHASIA & WERNICKE’S APHASIA

4. 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.

5. 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.

6. 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.

7. 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.

8. 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: • Exercises in reading • Exercises in writing • Exercises in following directions • Repetitions of what they hear • Computer-aided therapy