Johannes Gutenberg-Universität Mainz
Proseminar: “Bilingualism - Multilingualism”
WS 2000/2001, 7th semester

Aphasia

von: Mieke Karoline Anna Schüller

Table of Contents

1. Introduction 3

2. A Survey of the Brain Structure and the Language Areas 4

3. Aphasia 6

3.1. A Definition of the Term Aphasia and the Causes of Aphasia 6
3.2. The Main Types of Aphasia 7
3.3. The Recovery from Aphasia 9

4. Aphasia in Bilingual and Multilingual Persons 10

4.1. Aspects of the Research on Aphasia in Bilinguals and Multilinguals
4.2. Different Theories of Additional Language Areas 11
4.3. The Recovery of Bilingual and Multilingual Aphasic Patients 12

5. Conclusion 14

Bibliography 16

1. Introduction

Brain diseases and disorders are fields of neurology that have still not been fully examined. Neurologists are constantly facing new mysteries concerning the processes that take place on in the brain. Especially the aspect of language offers a wide spectrum for research, from the medical point of view as well as from the linguistic one. As I will concentrate on the aspect of language, or more precisely the affection of the faculty of language, which means its production and comprehension, the affection aphasia offers a good example. Aphasia is a very complex problem, and it is still not totally examined by scientific researchers and brain specialists. The field of aphasia includes many different kinds of aphasia, different clinical pictures, symptoms, and recovery patterns. At any rate, the patients have difficulties in producing or understanding language, although to different degrees.

Aphasia in bilingual and multilingual persons is a field of neurology that deserves further research. It offers new aspects to the research on brain activity, and it offers the opportunity of approaching the problem of aphasia in a new way. Nevertheless, there are different, one word even contradicting theories from specialists all over the world concerning the impact of aphasia on speakers of more than one language and the reasons for it, some of which will be presented in this research paper.

As this research paper is written in order to take a closer look at the problems with language in aphasia, it is inevitable to present some medical facts and theories in order to explain the impact of aphasia on the production, understanding and recovery of language. I will start with an introduction to the physical structure of the brain, especially on the areas that are associated with language. Further on, a definition of aphasia, its causes, and a description of the different types of aphasia and their specific symptoms will be given. As the process of recovery is extremely interesting and the observation of it important because it allows us to draw conclusions on how the brain works, a section of the research paper will be devoted to this point. Moreover, the case studies of bilingual and multilingual aphasic patients offer interesting aspects for linguistic and medical research because of the possibility of understanding how language is stored in the brain, and whether different languages are stored in different parts of the brain, perhaps even in the other hemisphere. Furthermore, the way in which bilingual and multilingual aphasic patients recover their language is interesting as well. Ultimately, I hope that this research paper on aphasia will help to give an insight into scientific research, and the way aphasia affects the language abilities of monolingual people as well as bilingual and multilingual people.

2. A Survey of the Brain Structure and the Language Areas

The largest part of the human brain is the cerebrum, which is divided into the left and the right cerebral hemispheres. The two hemispheres are connected by the brain stem, which can be further subdivided into the mid-brain, the pons and the medulla oblongata. It is an interesting fact that each hemisphere controls the opposite side of the body. Furthermore, it is often said that the left hemisphere is dominant for analytical tasks, while the right hemisphere is associated with creative abilities and emotional expression. But this way of defining the functioning of the hemispheres would oversimplify the processes that are going on in the brain. Scientific research has shown that the dominance for one ability often cannot be clearly assigned to only one of the hemispheres. Even the idea of the asymmetrical functioning of the hemispheres does not apply to all patterns, as the example of language shows. Generally, it is considered as an established theory that the left hemisphere is dominant for language in right-handed people. But this does not automatically allow the conclusion that the right hemisphere is dominant for language in left-handed people, because “[l]eft-handers are by no means a homogeneous group, and in over 60% of cases the left hemisphere is either dominant for language or very much involved (mixed dominance)” (Crystal 258-59).

The surface of the cerebrum, the so-called cerebral cortex, is made of grey matter, which consists of nerve cells. Beneath the cortex is a body of white matter, consisting of fibre tracts, which transmits signals between the different parts of each hemisphere and between the cortex and the brain stem. The surface of the cortex is folded in on itself, and thereby produces many convulsions. These convulsions are separated by fissures. The median longitude fissure separates the two hemispheres, but it does not extend through the whole cerebrum; lower down, the hemispheres are joined by the corpus callosum. Through this connection, information can be transmitted from one hemisphere to the other.

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