Chapter 12 Language And Brain (1) neurolinguistics神经语言学 the study of the relationship between brain and language, including research into how the structure of the brain influences language learning, how and in which parts of the brain language is stored, and how damage to the brain affects the ability to use language
1) the structure and function of the human brain 1. the structure of the human brain
? The brain consists of about ten billion nerve cells called neurons神经元 and the billions of fibers that
connect these neurons.
? The neurons are the basic information processing units of the nervous system. ? The brain is divided into two sections: the brain stem 脑干(the lower section) cerebrum 大脑(the higher section)
The brain stem, connecting to the spinal cord and shared by all animals, keeps the body alive by maintaining the essential functions such as respiration, heart rate, and muscle co-ordination. The cerebrum that differs in different species is not essential for life.
? The neurons form the surface of the brain, which is called the cortex脑皮层.
? The cerebral cortex is the decision-making organ of the body and storehouse of ―memory‖. It receives
messages from all the sensory organs and initiates all voluntary actions.
? It is the cerebral cortex that accounts for the human distinctness in the animal world. Animals, reptiles and
amphibians, for example, have no cortex at all.
? The cortex is separated by the longitudinal fissure into two parts: the left cerebral hemispheres (the left brain) the right cerebral hemispheres (the right brain)
? The two parts of brain are connected by a bundle of nerve fibers known as corpus callosum胼胝体, a
pathway leading one to another, allowing the two parts to communicate with each other. 2. the function of the human brain
? Each hemisphere controls the opposite half of the body in terms of muscle movement and sensation.
? With respect to higher cognitive functions, generally the left hemisphere seems to excel in analytic tasks such
as arithmetic, whereas the right hemisphere excels in tasks which require an overall appreciation of complex patterns such as the recognition of familiar faces and melodies.
? Though the left and right brains show distinct abilities and responsibilities, complex mental activities such as
language do not always fall neatly into one brain or the other but involve the coordinated functioning of both brains.
? Most right-handed individuals have language represented in the left brain and are therefore said to be left
lateralized for language. But not every aspect of language is represented in the left brain of right-handers. ? Few left-handers have language localization in the right brain. Rather they tend to show significant language
representation in both brains. Thus left-handers are generally less lateralized for language. 2) evidences for lateralization autopsy studies
3) methods in the study of the brain : 1. SAT 2. CT scanning 3. PET
4) methods to examine the behavior associated with the brain: 1. dichotic listening 2. split brain studies
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5) aphasia/dysphasia失语症 loss of the ability to use and understand language usually caused by damage to the brain 1. Broca‘s aphasia
? Broca‘s area is responsible for the articulation of speech. Damage to it might cause non-fluent aphasia. ? non-fluent aphasia global aphasia (completely mute, the most severe form) Broca‘s aphasia (less severe form)
? Phonologically the speech of Broca‘s aphasics is very halting and lack of normal sentence intonation. ? Syntactically, Broca‘s aphasics produce telegraphic speech. They often show difficulty judging the
grammaticality of sentences.
? Most Broca‘s aphasics show writing disturbances that are comparable to their speaking deficits. 2. Wernicke‘s aphasia Damage to parts of the left cortex behind the central sulcus大脑回间沟 results in a type of aphasia called fluent aphasia.
? In sharp contrast to the non-fluent aphasics, fluent aphasics have no difficulty in producing the language.
They can speak very fluently with normal pronunciation and intonation and correct word order but often with little semantic meaning
? They often have great difficulty in comprehending a speech.
? The most important type of fluent aphasia is called Wernicke‘s aphasia.
? Unlike Broca‘s aphasics, Wernicke‘s aphasics are generally unaware of their deficit.
? Wernicke‘s aphasics also show reading and writing deficits comparable to their deficits in speaking and
listening.
? The written production of Wernicke‘s aphasics is formally very good with correct spelling and handwriting,
but like their speaking, makes little sense.
? Reading comprehension is also severely impaired in Wernicke‘s aphasia.
? Normal language use is a marriage of content and form. In the case of non-fluent aphasia, form is
compromised but the content of language remains relatively intact. In contrast, fluent aphasia is characterized by a rapid flow of form with little content. (2) psycholinguistics心理语言学 Psycholinguistics is the study of language processing. It is concerned with the processes of language comprehension and production. 1) types of speech error 1. spoonerism/reversal error type of speech errors when the position of sounds, syllables, or words is reversed e.g. a blushing crow a crushing blow
e.g. I have a half warmed fish. I have a half-formed wish (in my mind). e.g. ?Let‘s have chish and fips‘ instead of ?Let‘s have fish and chips‘
e.g. ?You have tasted the whole worm‘ instead of ?You have wasted the whole term‘
吹疵求毛, 假劣伪冒,离出提婚,抽酒喝烟, 刷脸洗牙, 我的孩子生了三个侄子。 有没有人找电话打我呀？
你这样吃痘痘，能不长奶油吗？ 米饭，我的小姐怎么还没来，快点！
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把萝卜拿来切菜刀, 以君子之心度小人之腹, 苹果多少斤一钱? 2. anticipation error when a sound or word is brought forward in a sentence and used before it is needed e.g. ?I‘ll put your cat in the cupboard‘ instead of ?I‘ll put your hat in the cupboard‘ e.g. 便前便后要洗手。（饭） 三天打网，两天晒网。（鱼） 今天要下伞,把伞带上吧！（雨） 他哥既会游足球也会游泳。（踢） 3. perseveration error when a sound or word which has already been uttered reappears e.g. ?the president of Prance‘ instead of ?the president of France
e.g. 关于打击假币的行动，下一币应该? (步) 话匣子一打开就开个没完。（说） 公路局的马局长来过吗？（处长） 房里没冷气，当然就会冷汗淋漓啦！（大） 2) experimental methods 1. lexical decision
2. the priming experiment 3. timed-reading experiments 4. eye movement experiments
5. event-related potential experiment
3) language processing
? When a person hears a sentence, he performs phonetic analysis to isolate phonemes and word boundaries,
and to relate these to representations in the mental lexicon. This inductive analysis is referred to as bottom-up processing.
? We do not wait until we have analyzed all the phonemes in a sentence before we begin to try to understand it.
Rather, we begin interpretation of a sentence spontaneously and automatically on the basis of whatever information is available to us. This is called top-down processing. 1. phonological processing
? According to cohort model, in word comprehension, words are analyzed by hearers from beginning to end.
The beginning-to-end analysis proceeds one phoneme at a time rather than one syllable at a time.
? Other evidence shows that the syllable plays an important role in speech perception. It was concluded that in
normal auditory analysis, subjects first break down stimuli into syllables and then into individual segments as the situation demands. 2. morphological processing
? For most multimorphemic words, individual morphemes are automatically activated during word
recognition.
? Knowledge of the selectional restrictions of affixes does indeed form part of the word-processing system. It
was found that response times were significantly longer for illegal nonsense words than for the morphologically legal words. 3. syntactic processing
? A garden path sentence is an awkward sentence that misleads the syntactic parser and takes it down the
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garden path to the wrong analysis. e.g. The horse raced past the barn fell.
? It has been claimed that the garden path effect results from two principles of parsing: minimal attachment
and late closure.
? The minimal attachment strategy states that we prefer attaching new items into the phrase marker being
constructed using the fewest syntactic nodes consistent with the rules of the language. e.g. Ernie kissed Maricie and her sister… a. Ernie kissed both Maricie and her sister b. ?Ernie‘ and ?her sister‘ are the subjects of two sentences respectively.
? The late closure strategy states that, wherever possible, we prefer to attach new items to the current
constituent.
e.g. Tom said that Bill had taken the cleaning out yesterday. a. ?yesterday‘ is closely related to the object clause. b. ?yesterday‘ is closely related to the main clause. ? sentence ambiguity
e.g. The word rose in They all rose is ambiguous. It can be related either to stand or to flower. Experimental results show that in processing a sentence, we create all representations possible and then discard the ones that are either incorrect or unnecessary. ? Psycholinguistic modeling (by Levelt) four stages of production: conceptualizing formulating articulating self-monitoring
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