Language and the Brain

lyric and the maven Mevery pack assume the physical basis of expression lies in the lips, the tongue, or the ear. But deaf and mute people commode also possess lingual colloquy to the full. People who thrust no mental competency to use their vocal cords whitethorn still be capable to comprehend lecture and use its written forms. And human sign linguistic communication, which is found on visible gesture preferably than the creation of sound waves, is an incessantly creative system just like spoken forms of oral communication.But the basis of sign talking to is not in the contact, just as spoken linguistic process is not based in the lips or tongue. There are more another(prenominal) examples of aphasics who lose both the ability to write as salubrious as to express themselves utilize sign- diction, in so far they never lose manual sleight in other tasks, much(prenominal) as sipping with a straw or tying their shoes. Language is brain stuffnot tongue, lip, e ar, or hand stuff. The vocabulary organ is the mind.More specific totallyy, the verbiage faculty seems to be located in indisputable sweeps of theleft hemispheric cortex in most profound adults. A special branch of linguistics, New medical imaging techniques such asPETandfMRIhave allowed researchers to generate pictures showing which expanses of a living brain are active at a pr single time. In the past, research was primarily based on observations of loss of ability resulting from damage to thecerebral cortex.Indeed, medical imaging has represented a radical rate forward for research on savoir-faire communication processing. Since then, a whole serial of relatively large areas of the brain have been found to be mingled in reference processing. In more recent research, subcortical regions (those manufacture below the cerebral cortex such as theputamenand thecaudate nucleus) as healthy as the pre-motor areas (BA 6) have received increased attention.It is now by and la rge assumed that the following structures of the cerebral cortex near theprimary and unessential auditory cortexesplay a fundamental mathematical function in speech processing * Superior temporal gyrus(STG)morphosyntacticalprocessing (anterior section), integration ofsyntacticandsemanticinformation (posterior section) * Inferior frontal gyrus(IFG,Brodmann area(BA)45/47) syntactic processing,working memory * Inferior frontal gyrus(IFG,BA 44) syntactic processing, working memory * Middle temporal gyrus(MTG)lexical semanticprocessing The left hemisphere is usually dominant in mightily-handed people, although bilateral activations are not uncommon in the area of syntactic processing. It is now accepted that the right hemisphere plays an important role in the processing of suprasegmental acoustic features likeprosody. Most areas of speech processing develop in the second year of life in the dominant half (hemisphere) of the brain, which ofttimes (though not necessarily) corresponds to the opposite of thedominant hand. 8 percent of right-handed people are left-hemisphere dominant, and the majority of left-handed people as well. What pile diction disorders tell us about the brains lecture areas? Tourettes syndrome, which produces random and involuntary emotive reflex responses, including vocalizations This type of disorder, which often affects language use, is faced by a disfunction in the subcortex. There is no deform which prevents the slightest stimulus from producing a vocal response, sometimes of an inappropriate manner using abusive language or chaps. These words are involuntary and often the affected individual is not even aware of uttering them (like um in umpteen individuals) and only realizes it when video is played back.This syndrome is not so much a language disorder per se as a disorder of the filters on the adult emotional reflex systema kind of expletive hiccup. True language is housed in the cortex of the left hemisphere, not in the subcorti cal area that controls involuntary responses. Certain types of brain damage can affect language production without actually eliminating language from the brain. A byzant that damages the muscles of the vocal apparatus may leave the abstract cognitive structure of language intactas witnessed by the fact that right hemisphere stroke victims often understand language perfectly well and write it perfectly with their right handalthough their speech may be slurred due to lack of muscle control.We have also seen that certain disorders involving the subcortexthe seat of involuntary emotional responsemay have linguistic side effects, such as in some cases of Tourettes syndrome. But what happens when the areas of the brain which control language are affected directly, and the individuals abstract command of language is affected? We will see that language disorders can shed a great deal of light on the enigma of the human language instinct. SLI. One rare language disorder seems to be in natu ral(p) rather than the result of damage to a previously design brain. I have said that children are born with a natural instinct to prepare language, the so-called LAD however, a tiny minority of babies are born with an apparent defect in this LAD.Certain families appear to have a transmitted language acquisition disorder, labeledspecific language impairment, orSLI. Children born with this disorder usually have normal intelligence, perhaps even high gear intelligence, but as children they are never able to acquire language naturally and effortlessly. They are born with their window of opportunity already unopen to natural language acquisition. These children grow up without succeeding in getting any consistent grammatical patterns. Thus, they never command any language welleven their native language. As children and then as adults, their speech in their native language is a catalog of random grammatical errors, such asIts a flying birds, they are. These boy eat ii cookie.Joh n is work in the factory. These errors are random, not the cut back patterns of an alternate set phrase the next conversation the same SLI-afflicted individual might severalizeThis boys consume two cookies. These sentences, in fact, were uttered by a British stripling who is at the top of his class in mathematics he is highly intelligent, just grammar blind. SLI poseers are incapable of perfecting their skills through being taught, just as some people are incapable of being taught how to draw well or how to see certain colors. This is the best proof we have that the language instinct most children are born with is a skill kinda distinct from general intelligence.Because SLI occurs in families and seems to have no environmental cause whatsoever, it is assumed to be caused by some hereditary factor plausibly a fluctuation, recessive gene that interferes with or impairs the LAD. The precise gene which causes SLI has yet to be located. Aphasia We know which specific areas of th e left hemisphere are twisty in the production and processing of particular aspects of language. And we know this primarily from the report of patients who have had damage to certain parts of the left hemispheric cortex. toll to this area produces a condition calledaphasia, or speech impairment (also called dysphasia in Britain). The study of language loss in a once normal brain is calledaphasiology. Aphasia is caused by damage to the language centers of the left hemisphere in the region of thesylvian fissure.Nearly 98% of aphasia cases can be traced to damage in theperisylvian areaof the left hemisphere of the cerebral cortex. Remember, however, that in the occasional individual language is localized elsewhere and in children language is not yet fully localized. SUMMARY Lets sum up three important facts about language and brain. First, humans are born with the innate capacity to acquire the extremely complex, creative system of communication that we call language. We are born wi th alanguage instinct, which Chomsky calls the LAD (language acquisition device). This language aptitude is completely varied from inborn reflex responses to stimuli as laughter, sneezing, or crying.The language instinct seems to be a uniquely human genetic endowment nearly all children exposed to language naturally acquire language almost as if by magic. Only in rare cases are children born without this witching(prenominal) ability to absorb abstract syntactic patterns from their environment. These children are said to suffer fromSpecific Language Impairment, orSLI. It is thought that SLI is caused by a mutant gene which disrupts the LAD. The LAD itself, of course, is probably the result of the complex interaction of many genesnot just oneand the malfunction of some single(a) reveal gene simply short-circuits the system. For example, a faulty carburetor wire may prevent an engine from running, but the engine is more than a single carburetor wire.Many thousands of genes contribu te to the makeup of the human brainmore than to any other single aspect of the human body. To isolate the specific set of genes that act as the blueprint for the language organ is something no one has even begun to do. Second, thenatural ability for acquiring language normally minor rapidly somewhere around the age of puberty. There is a lively agefor acquiring fluent native language. This phenomenon seems to be connected with thelateralizationof language in the left hemisphere of most individualsthe hemisphere associated withmonolinear cognition(such as abstract reasoning and step-by step physical tasks) and not the right hemisphere, which is associated with 3D spatial acuity, artistic and musical ability.Unlike adults, children seem to be able to affiance both hemispheres to acquire language. In other words, one might say that children acquire language three-dimensionally while adults must learn it two dimensionally. leash and finally, in most adultsthe language organ is the pe risylvian area of the left hemispheric cortex. Yesterday we discussed the extensive catalog of evidence that shows language is usually housed in this specific area of the brain. Only the human species uses this area for communication. The signals of animal systems of communication seem to be controlled by the subcortex, the area which in humans controls standardized inborn response signals such as laughter, crying, fear, desire, etc.