Broken English: The Effects of Brain Damage on Language

[MUSIC PLAYING]

What's your name?

Um, um--

Is it--

Ryan.

Ryan. And your first name?

Gordon

Gordon. Gordon--?

Gordon--

Gordon-- Ryan.

Ryan, yes.

How old are you, Gordon?

At a tragically early age, this amiable mansuffered a stroke as the result of a cerebralhemorrhage on the left side of his brain.

In your 50s?

It left his mind and personality intact whilstrobbing him of the capacity to express histhoughts in language.

Tell me, I hear that you were in politics.

Well, I-- yes.

Which party were you? What, the good party, orthe party that's winning?

Yeah.

Mr. Carr. Now how long ago did you have youroperation?

Three years November.

And how far away do you live?

About 20 minutes by car.

And you drive yourself?

Yes.

A few years ago this man underwent an operationfor the removal of his larynx. That meant that hecould no longer use his voice-box to speak. Andyet there's nothing wrong with his language.That's to say, although his voice sounds unusual,his vocabulary and grammar are just like anyoneelse's. He understands exactly what's said to himand he gives completely intelligible replies.

Do you still find it a lot of work after three years?

Oh, yes. Sometimes. I mean, it depends on howyou feel.

Is there a limit to the length of time that you canspeak without having to take a rest?

Not necessarily. Some days are better than others.

So what you've just seen is not a disorder oflanguage, but rather, an unusual way ofexpressing it. Or to be more accurate, it's anunusual way of making itself heard. In fact, what'sso striking about this case is the fact that whenthe communicative faculty is intact, it willsuccessfully redistribute efforts and will executeits commands by using completely new channels.

Tell me how they trained you to use your stomachfor talking.

It was just-- a speech therapist come to the house,and she'd say it [INAUDIBLE].

And was a very difficult for you at the beginning?

It was. It was, of course.

You see, this man swallows air. And by controllingthe expulsion of the air from his stomach, he canstill make himself understood. In fact, if you wereto write down an exact transcript of everything hesaid, a reader who hadn't had the benefit ofhearing him speak would never suspect that therewas anything wrong at all.

--But you've got to talk all the time you'rewalking. Gotta get so you can speak.

Now here's someone who illustrates the pointrather more vividly. Now unlike the man we'vejust seen, Cindy O'Grady has a completely intactvocal apparatus. But since she's deaf, and hasnever heard anyone else use their voice, and grewup in a family which used sign language, she usesa completely different set of muscles stories tomake herself understood.

Now, if you watch her without the benefit of thesimultaneous translation, which you'll hear in amoment, you might easily think that she was at aloss for words, and that all that hand-waving wassimply a way of trying to attract my attention. Butif I now let you listen to the simultaneoustranslation, you can hear that nothing of thesource is going on at all.

--You must know the exact special relationshipamongst things and set the up in sign-spaceaccordingly. People with right hemispheredamage have problems with that, problemssetting things up correctly in space. They really--

The paradox is that the person Cindy is talkingabout has got something wrong, because she'sactually describing a deaf patient who has lost theability to sign. Not because her hands wereinjured, because brain damage had affectedlanguage. And that's what this program is allabout.

--And things to the right side of that room, theyjumble things up.

Now 80 years ago, the Swiss linguist de Saussurepointed out that the signs which were used inlanguage were arbitrary. Now what he meant bythat was not what Humpty Dumpty meant-- that's to say that words can mean whatever you wantthem to. No, what he meant was that with theexception of certain rare words, the ones we callonomatopoeic, neither their sound nor theirappearance on the page had any relationship towhat they referred to.

I think you can see this quite clearly if youconsider the pieces which are used in playingchess. Although all these pieces are quite familiar,their appearance has nothing to do with theirfunction in the game. That means that I couldsubstitute pieces of paper on which I've writteneither numerals or letters of the alphabet.

And that's what I've done on the other side of theboard. You can see that all the pawns arerepresented by the same alphabetical symbol, A,the rooks by F, and so on and so forth. Now aslong as each player understands what eachalphabetical symbol stands for, and as long asthere is no visible confusion between them all, thegame of chess can go ahead all right. In otherwords, the game employs a purely formal systemof contrasts.

Well, the same principle applies to language. Aslong as the system has a formal structure, and aslong as all the characters or symbols areunambiguously distinct from one another, itdoesn't matter what sort of stuff they're all madefrom.

I think it's quite obvious that this astonishinglyeloquent young woman has switched to acompletely different channel. And unlike the manwho is trying to vocalize but using a ratheranomalous method to do so, Cindy is using herhands to do the same job.

Another example is that-- well, for example, theright sign for sick is this. If a person has beensickly all their lives, you repeat that sign.

The point is that although speech is ratheranomalous in the first example and completelyabsent in the second, language, language iscompletely intact in both cases. In each one, youcould transcribe the output and never suspectthat anything was wrong.

Now one of the problems with language is that itseems so unproblematic. That's partly becausewe perform it so effortlessly. So you might want tosay, well, it just happens and that it's thereforeself-explanatory. No problem.

But that's not quite it either, because there arelots of other things we do without having to thinkabout them, and we can't explain why theyhappen. And as soon as you do start thinkingabout them, they do seem problematic. Forexample, I can blush and I can sweat, but Icertainly can't tell you how I can do it. And myheart speeds up whenever I run, but I can'tchoose to accelerate it. And so how it happens isreally quite difficult to explain.

But when it comes to speaking, the mere fact thatI intend to do it, I mean to speak, somehow seemsto explain how I do it. I do it because I want to.And the same thing seems to go for walking. Sowhat's the problem, you might say.

Well, that is the problem. One of the best ways ofseeing just how problematic it is and just howmuch unconscious machinery is involved in anotherwise conscious process, is to look atsomeone whose language machinery, as opposedto their speech machinery, someone whoselanguage machinery has been damaged.

Isn't it a--? I'm going to use it, and you tell mewhat it is.

Yeah. No. Yes.

And what is it? A--?

Kurat.

K, K--.

Kulago.

A comb.

Ladzone.

A comb.

Now although this man seems to have someproblem in articulating speech, I think you'llagree the most striking feature is that hislanguage has undergone a change.

So, it's called a--?

Foam.

Comb?

Mome. Bey, um-- yeah.

I'm sure you'll remember that Lewis Carroll oncepointed out if you take care of the sense, thesounds will take care of themselves. Well, fromlistening to this patient, one gets the impressionthat he has a perfectly good grasp of his ownsense. But he seems to be short of the words thathe needs to express that sense, that the signs, inother words, are not taking care of themselves.

What do you call what you're doing?

Uh, no.

Is it brushing?

Brushing? Brushing?

Is it really brushing, or isn't it--

No, no.

No. He knows what he wants to say, and from thefew words he does say, you can see that his voiceis in perfect working order. Now that can onlymean that something has gone wrong in that partof his brain which somehow turn sense into signs.

Uh, write.

There you are, you see? You can say write.

Yeah.

Good.

Well, some time ago the patient you've just seenhad a stroke. That means that as a result of ahemorrhage from one of the arteries supplyingthis part of the brain here, it looks as if thenervous apparatus concerned with theformulation of spoken language-- not speech, butspoken language-- has been impaired. In fact, youcan see what's happened from this translucentarea here on the CAT scan. These little translucentareas here, which are picked out in black against apaler grey background show where the lesion is,here, on the left side of the patient's brain. It's theright side of the picture, but it's left side of thepatients brain.

In fact, it was a discovery of this sort whichrepresented the first material evidence thatpsychological functions were localized at differentanatomical sites in the human brain. Theinteresting point is that even without suchevidence, early 19th century scientists had begunto theorize along these lines.

One of the most distinctive features of the periodwhich is often referred to as the Enlightenmentwas a preoccupation with the material basis ofhuman nature. And for the first time, it began tolook as if there might be such a thing as thescience of man. But as often happens whenintellectual ambitions are framed on this scale,philosophers sometimes try to run before theycan walk. And one of the most conspicuousexamples of such premature optimism is to beseen in the theory known as phrenology.

Of course, human beings have always beenpreoccupied with the task of classifying individualdifferences. And yet with the so-called science ofphrenology, philosophers were convinced thathearsay and anecdote were finally replaced byanatomical certainty. The scheme wasinaugurated by the Austrian anatomist Franz Joseph Gall, who visualized the brain not so muchas one organ, but rather as a whole cluster of them. As far as he was concerned, each of thesecerebral organs-- none of which was, incidentally,visible to make the naked eye-- was somehowresponsible for the various mental faculties.

There was, for example, an organ of veneration,an organ for self-esteem, for love of approbation,for wonder, and for amativeness. The theory wasthat if any one of these organs was conspicuouslylarger than normal, the person would displaycorresponding psychological traits. The idea wasthat the overgrowth of any one of these organswould cause a palpable lump in the overlyingskull, so that by running your hands over thecranium of the subject, you could diagnose his ordistinctive character.

Unfortunately, this persuasive theory was notsecurely tied down at either end. For one thing,the brain does not display any visible provinces.And as for the various faculties, they now seem tobe quite arbitrary distinctions. They certainlydon't correspond to anything that we would call anatural kind.

In spite of this, the inevitable soon happened, andthe brain became balkanized to accommodatethe rapidly multiplying list of hypotheticalfaculties. It was even thought that there was aorgan for something called philoprogenitiveness,or the love of creating offspring. Well, in the midstof all this phrenological enthusiasm, somethinghappened which altered the shape ofneurological thought.

This is one of the most famous brains in thehistory of science. After more than 130 years inpickle, it doesn't look very impressive. And yet itmade the man to whom it belonged very famousindeed, not, as with most famous men, for whathe did, but rather for what he couldn't do.

He was a patient in the Bicetre hospital in 1860.He came under the care of a young Frenchneurologist called Paul Broca, who was struck bythe strange peculiarity of his unfortunate patient'sspeech. When the patient died and came toautopsy, Broca found but that was a large fluid-filled cyst on the lower part of the left frontal lobe,just above the cleft which anatomists refer to asthe sylvian fissure. Broca suggested that theconvolution on the left side now replaced by thecyst was responsible for the production ofarticulate language.

For neurologists at that time, this was arevolutionary conclusion, since it was generallyassumed that biological functions weredistributed symmetrically. By stressing thelinguistic predominance of the left side of thebrain, Broca established one of the fundamentalaxioms of modern neurology.

So you might want to ask, how is it that an injuryon one side of the brain which paralyzes muscleson the opposite side of the body seems to strayover to the other side as far speech is involved?Well, the solution to this paradox takes me backto what I was saying at the beginning of theprogram. Because unlike the patient we sawearlier on whose voice had been affected, inBroca's case, it wasn't the voice as such whichwas the problem, but rather the patient's abilityto use the voice for the purpose of utteringspeech. In fact, for every other purpose, themuscles of lips, tongue, and larynx were in perfectworking order, unlike the muscles on the rightside of the body, which were completelyparalyzed.

Well, all the same, although he could see that themuscles which would otherwise have beenemployed for speaking were not actuallyparalyzed, Broca assumed that the area of thebrain whose special function was to recruit thesemuscles into the service of speech had beeninactivated. Well, until recently, this conclusion ofhis had become a neurological dogma.

Broca's area was regarded as the executive highcommand for the production of articulate speech.A few years ago, though, a discovery was madethat seemed to suggest that the traditionaldogma about Broca's area might have to bemodified. In 1981, by one of those rare strokes ofmisfortune, nature offered science an unsolicitedand somewhat puzzling gift.

A young American woman who'd been born deafsuffered a stroke which affected the left side ofher brain. Now she was predictably paralyzeddown the right side of her body, so that her righthand was no longer available to perform any task.But the really surprising thing was that althoughher left hand was completely unaffected as far aspractical tasks were concerned, it behaved as if itwas paralyzed when it came to signing, eventhough she'd been fluent in sign ever sincechildhood.

Mom, brother, drive.

Oh, you were in the car? Or were you outside ofthe car?

No, no, no.

You were inside the car? Were you standing withyour mom?

No, no. Brother, drive, drive, brother, huh?

As you can see, her right arm is motionless. Butalthough she uses her left arm for both drinkingand for smoking, when it comes to signing, thelimb becomes more or less incompetent. Let's runthat again.

Now although you are not familiar with sign,those who are assure me that this unfortunateyoung woman is just as much of a loss for wordsas the stroke patient you saw earlier.

Mom, brother, drive.

Oh, you were in the car? Or were you outside ofthe car?

No, no, no.

You were inside the car? Were you standing withyour mom?

No, no. Brother, drive, drive, brother, huh? Rightthere.

Now although as yet there are very few cases likethis, the implications could be very far-reachingindeed. because the findings seem to upset thetraditional assumption that Broca's area isexclusively concerned with recruiting the muscleswhich are involved in articulate speech. You see,the fact that an injury to this area can thwart anyexpression of language, vocal or manual, couldonly mean that Broca's area is specialized neitherfor speech nor for sign, but rather for elaboratingsome abstract plan of performance which iscommon to both. It just so happens that themuscles of the voice, tongue, and jaws are theones which are normally used to execute thisplan. But if for some reason these resources arenot available, it seems that the program which isrepresented in this part of the brain is versatileenough to commandeer an alternative mode ofexpression.

In contrast to the deaf patient with the stroke, thiseloquent young woman can make herselfunderstood to anyone who is familiar with sign.The paradox is that she's using sign to speakabout someone who can't use it.

Meaning that after the stroke, he was reduced tosingle signs. So for example, in his signedsentence, he might say girl, boy, cookie, give.

Well, this brings me to an important distinctionwhich was first introduced in linguistics by theAmerican Noam Chomsky. One of his manycontributions to the study of language is thecontrast he drew between competence andperformance-- that's to say, between a deeplystructured potential for language as opposed tothe actual performances which release thispotential.

Perhaps you can think of it like this. If at the endof my life, yours, or anyone else's for that matter,some conscientious recording angel had writtendown everything that you, I, or anyone else hadsaid, he would have compiled a large butnonetheless finite set of utterances. On the otherhand, there's no limit to the number of sentencesor indeed to the length of any one sentence whichyou or I might have uttered if we had had themisfortune to have lived forever, so that asChomsky quite rightly points out, although ourlinguistic performance is finite, our linguisticcompetence is boundless.

Once again, you can think of it, if you like, in termsof chess. Although the rules of chess don't specifyany of the moves which ought to occur, theyintroduce serious constraints into the range ofpossible moves. And although each gamedevelops completely unprecedentedconfigurations on the board, the transition fromone configuration to the next must obey the rulesin order to be acceptable.

Well, I suspect that it was something like this thatLewis Carroll had in mind when he had the UglyDuchess say that as long as you take care of thesense, the sounds will take care of themselves. Heseems to have known, long before Chomsky, thatthere was some sort of mental machinery whichmediated between sense and sound, whichensured that what was uttered expressed thesense in a grammatically acceptable form.

Dear child--

In fact, if you look at this short sequence of a filmof Alice which I made many years ago, you can seehow much Carroll was aware of the problems oflanguage.

And the moral of it is-- 'tis love, 'tis love makes theworld go 'round.

I thought it was done by everybody minding their own business.

Ohh, oh. Well, yes. Well, it means much the samething. And the moral of that is, take care of thesense, and the sounds will take care ofthemselves.

It's no accident that Lewis Carroll played suchfanciful games with language, since he was, byprofession, a mathematical logician. And it wasthe rapid development of this discipline whichlaid the foundations for what's now called theChomskyan Revolution. But meanwhile, thesituation was made even more interesting by thediscovery of further clinical information whichneatly complimented what Broca had discovered.

You do have a nice clear way of putting things.

In 1874, the German urologist Wernicke publisheda report of nine cases whose symptoms were, toall intents and purposes, a mirror image of theones which had been described 10 years earlier byBroca. Now these patients spoke with an almostincontinent fluency, in contrast to the patientsuffering from Broca's aphasia, whose speech,when there was any, tended to be halting andtelegraphic, conspicuously lacking many of theso-called functional parts of speech-- articles,conjunctions, prepositions, and so forth.

Now although Wernicke's patients were strikinglyfluent by comparison, he noticed that the outputwas curiously incoherent, with odd transpositionsof syllable, and often included nonsense words orneologisms. But he also noticed that there wasanother important contrast. Whereas Broca'sdumbstruck patients appeared to understandwhat was said to them, Wernicke's patients couldneither understand nor repeat what was said tothem. Now here's a patient who shows at leastsome of the features which Wernicke hadrecognized in 1874.

Which part of Canada do you come from?

Where'd I go?

No, which part of Canada do you come from?

From London, England.

Or London, Ontario.

Yes. Yes. I was young. And now we went toLondon, England a port city. I went to Montrealand Canada here, was 1900. No.

Now this lady had a stroke on the left side of herbrain when she 80.

280. I can't you know addresses right.

The symptoms are not nearly as severe as theywere in the earlier stages of her illness.

558, oh dear. If I was 50 in the [INAUDIBLE] and now I'm 803 now--

You're not 803.

Oh, but I am. Well, I don't give the first. I know canI write it. You do one, eight, and then now it's tobe a 10, the dough. That's me.

So you're 83.

Yes.

In cases like this, the injury is consistently foundsomewhat further back in the brain, but you'll stillnotice, it's on the left side. Now since this areahere was known to be associated with hearing,Wernicke concluded that this was probably wherethe acoustic representation of words was stored.

Wernicke proceeded to theorize on theassumption that the area now named after himwas responsible for the acoustic representation ofwords, and that since Broca's area was apparentlyspecialized for vocal production, he proposedthat their was in all probability a flow ofinformation in which the memory traces for thesound of words were forwarded to Broca's area,where they excited the appropriate pattern ofmotor activity.

Well, with one theoretical blow, Wernicke hadinaugurated the long and still vigorous traditionof information flow diagrams. And although hehad no anatomical evidence to support his claimfor the existence of a pathway between his areaand Broca's, he predicted what you might expectto find if there were injury to this pathway. Such apatient, according to him, would be able tospontaneously utter speech and could alsounderstand what was spoken to him, but thatsince information could no longer be forwarded,you would expect to find that there was one sortof command which the patient would fail in alltogether, that he'd be unable to repeat sentences,for the simple reason that what he had heardcould no longer be transmitted to the area whichwould then issue the orders to speak it. And thisindeed is exactly what 's found in what is stillreferred to as conduction aphasia.

Statistical analysis.

Ta-titistis-- Ta-tictisis-- OK, forget it.

OK. How about this? They heard him.

They heard us.

They heard him talk on the radio.

They third heard a radido.

OK. We bought fruits, vegetables, and a quart ofmilk.

We had milk-- oh, give me again.

We bought fruit, vegetables and a quart of milk.

I bought-- something eat, thurse and a murse.

OK. Great.

John Hughlings Jackson approached aphasiawith a much less anatomical view of the matter.And although he recognized the curiouspredominance of the left hemisphere, heappeared to have little or no interest in the way inwhich the various functions might be partitionedwithin this hemisphere. He approached theproblem from a different direction altogether, orrather, from two directions. One was the result ofvisualizing the nervous system as the result ofbiological evolution, whereas the other stemmedfrom a more philosophical interest in the natureof language as such.

Let's see how he applied this to the nervoussystem. Well, as far as he was concerned, thesimple reflex was the basic unit of nervousfunction. The primitive nervous system was wiredto ensure that the creature would show a quick,reliable stereotype response to any stimuluswhich was applied to the surface. Here is a seaanemone responding to a harmful stimulus. Andhere is an equally stereotyped response to thepresence of food.

As Jackson saw it, each step up the evolutionaryladder endowed the nervous system with moreand more elaborate types of reflex action. And asmore complex circuits were inserted between thesensory input and the motor output, provisionwas made for more versatile behavior, whichmeant that the conduct of higher creatures wasno longer tied to immediate circumstances.Instead of getting a stereotyped automaticresponse on every occasion, higher creatures nowhad the opportunity to review the situation, torespond more flexibly, and even postpone actionaltogether.

Now although this scheme was not in itself anovelty, what was original was Jackson'sinsistence that neurological illness was simplyevolution played in reverse order. The moresevere the injury, the closer the behavior wouldregress towards the ancestral condition. Jacksonpredicted that the pathology of language wouldobey the same principles, and that whereas theintact nervous system endowed the person withthe linguistic creativity which was later to playsuch an important part in Chomsky's theory,injury would cause language to regress towardsan increasingly automatic condition, until in themost severe cases, one would see animpoverished residue of stereotyped expletives.

What is it?

Um. K-- Get-- Bit--

Try again.

Ge-- get-- damn! But-- but-- get--

All right. Watch my lips.

Giraffe.

That's it.

Giraffe.

Well, as Jackson saw it, the increasing poverty oflanguage was something much more complicatedthan simply a progressive loss of vocabulary. Incontrast to Broca and Wernicke, who bothvisualized linguistic pathology as a problem ofuttering and understanding words, Jacksoninsisted that thought was cast in the form ofsentences, or to use the surprisingly modern termwhich he employed, the proposition. Here's howhe put it.

It's not enough to say that speech consists ofwords. It consists of words referring to oneanother in a particular manner. Without this, averbal utterance would be a mere succession ofnames embodying no proposition. A propositionsuch as, "gold is yellow," consists of two names,each of which, by means of conventionalcontrivance of position called grammaticalstructure, modifies the meaning of the other.When we apprehend a proposition, a relationbetween two things is given to us.

By recognizing that words had to submit to somesort of formal arrangement in order to meananything useful, I think Jackson had anticipatedsomething which is now a fundamental axiom inlinguistic theory, namely that although wordshave to mean something in order to make asignificant contribution to a sentence, themeaning which they do contribute is stronglydetermined by the order in which they occur-- the"contrivance of their position," as Jackson said--and of course, by the meaning of all the otherwords with which they occur.

For example, although all the words in thefollowing two sentences are exactly the same,their respective meanings are quite different."The boy kissed the girl" is not saying the samething as "the girl kissed the boy." The fact that themeaning of a sentence can be altered just byreversing the order of two of its five words showsthat there's something about the formal structureof sentences which mysteriously assigns roles towhatever it is that some of the words refer to.

And yet the power of grammar is so great that aslong as the underlying propositional format of thesentence is preserved, it's surprising how manymeaningless words can be introduced and stillgive the curious impression that something'sbeing said. How about this poem by Lewis Carroll?

'Twas brillig, and the slithy toves/ Did gyre andgimble in the wabe;/ All mimsy were theborogroves,/ and the momraths outgrabe.

"Beware the Jabberwock, my son!/ The jaws that bite, the claws that catch!/ Beware the Jubjubbird and shun/ The frumious Bandersnatch!"

"'It seems very pretty," she said, when she hadfinished it, 'but it's rather hard to understand.' Yousee, she didn't like to confess even to herself, thatshe couldn't make it out at all. 'Somehow, itseems to fill my head with ideas, only I don'texactly know what they are. However, somebodykilled something; that's clear at any rate.'"

Well, like Alice, we are also afflicted by twocontradictory feelings when we hear this poem.There is something about it which indicates that itought to mean something, but there's somethingelse about it which makes it very hard to sayexactly what. The reason why Alice had suchparadoxical feelings, that she understood thispoem in spite of the fact that it was filled with somany meaningless words, is that without knowingthat she was doing so, she was applying a set oflinguistic rules, some of which enabled her toidentify the plausibility of certain words, althoughshe'd never encountered any of them before, andother rules which allowed her to recognize thegrammatical acceptability of the whole poem.And yet, Alice had no access to the set of ruleswhich allowed her to achieve thesediscriminations, anymore than we do when wesucceed in identifying nonsensical orungrammatical sentences in ordinary life. In fact,what Lewis Carroll's poem does is to challengethe vigilance of this native endowment and tobring some of its structural peculiarities out intothe open. And that, I think, is what is at lasthappening in neurolinguistics.

What's that a picture of?

Well--

What do you call that?

Souse. Souse.

A house.

Yes.

That's right. Yeah. It is a house. And what's that ontop of--

Yes. Chi-- chin in--

The chimney.

Chimney. Chimney.

Yeah, and what are these--

Under the direct influence of Chomsky's ideasabout the deep structure of language, we can dojust what Carroll did. That's to say, we can designlinguistic probes which include carefullycalculated anomalies. And by seeing how subjectsreact to them, it's possible to learn how thelinguistic machinery works.

And what do we call that?

Well, yes. Yes.

Is it a circle?

Cherkle.

A circle. But it's a circle with some figures writtenin it, aren't they?

Yeah. 1-2-3-4-5-6-7-8-9-10-11.

That's right. Now, when you see a circle with allthose numbers written around the edge, what doyou call that?

Yes.

Do you call it a sieve?

Yes.

Do you?

Well--

No, not really.

No, no, no.

No. Do you call it a cl-- cl-- a watch? A clock?

Yes! Yes.

So we have a clock here. Now what do you dowith a clock? Do you eat your dinner off it? OK. Sowhat do you do with a clock? You tell the--

Time.

Yeah. Now you tell me the time off this clock.

G. D.

So what time is it? Is it 8 o'clock?

No.

Is it 4 o'clock.

Yyyes.

Or is it-- look carefully. Is it 3 o'clock?

Yes!

OK. That's absolutely right.

In fact, with the advent of modern linguistics, I getthe impression that the study of aphasia hastaken a recognizable for the better. Because byhaving a clearer understanding about the sort ofthing that language is, I think we can make muchmore interesting hypotheses about the type ofmachinery that will be needed to realize it. Inother words, even if we knew nothing about thebrain whatsoever and had to regard the skull as ablack box whose contents were a completemystery, knowing as much as we do know aboutthe formal characteristics of language-- that's tosay, the logical rules by which it works-- meansthat we can make intelligent guesses about thesort of machinery that would have to exist insidethe head.

Well, now, this doesn't mean that there's no pointin trying to find out what is inside the skull. On thecontrary, it's a matter of great urgency to knowwhat sort of mechanism this program actuallyruns on. But until we know more about the logicalcharacter of the program itself, it's quite hard toknow what we would expect of any machinerywhich executes it.

This isn't a museum model of a dead brain. It's acomputerized reconstruction of a real onevisualized in life. Now if this sort of technique isanything to go by, it will surely change the nameof the game. In fact, as far as our understanding oflanguage is concerned, it will turn the wholeenterprise upside down.

Because before these techniques were available,there was no incentive to analyze the pathologicalpeculiarities of language beyond the point wherethey would allow the clinician to predict wherethe lesion was. But now we have a much moreefficient way of doing that, we can use ourknowledge of the lesion to help us to understandsome of the ways in which language works. Andsince linguistic knowledge itself is much moresophisticated anyway, we can probe the effects ofthe lesion with a much wider range of linguistictasks.

Now what makes the prospect even more excitingis that we could complement these studies bytechniques which actually allow us to visualizethe normal brain in the very act of processinglanguage. At the Montreal Neurological institute,they have a state-of-the-machine which canvisualize that parts of the brain which becomeactive when language is being used. These arecomputerized images in which the islands of lightrepresent areas of active brain function.

OK, Jonathan. You'll be laying in the scanner for aperiod of a couple of hours. We will at times giveyou a stimulation from the monitor, which will beabove your head. We'd like you to listen carefullyto instructions that I will give you before each ofthese studies, and lie still and don't be distractedby anything except that which you see on the monitor. OK. Is everybody ready? [? Ernst ?]? OK,on my count-- three, two, one, go.

It works something like this. A radioactivesubstance which happens to be an essentialingredient for cellular activity shows up in thoseparts of the brain which are undergoingparticularly heavy use. Experiments like this haveshown that given a linguistic task, theradioactivity shows up on the left-hand side of thebrain. As the resolution improves, it's quite likelythat we'll be able to see the distinctive changes inthe distribution of activity depending on thelinguistic tasks which are being applied.

For this condition, Jonathan, you will be seeing aseries of pictures of animals. I'd like you just tosee the animal, recognize the animal, but don'tsay anything. OK?

Up here, you can see the blood flow distributionin the brain under normal resting state. Patient'slooking at a fixed cross on a screen. This isactually the average for six different subjects, so itlooks a bit blurred. But you see the distribution ofthe blood around the outside of the cortex.

Over here, you see when the patient is looking ata picture. And there are a subtle differences at theback of the brain between the activated conditionand the resting condition. When you subtract thisfrom this, this is what you see. And you see, downhere, how these have become highlighted, andthere's essentially nothing else anywhere in theimage. So this has allowed us to focallyconcentrate on only that part of the brain which isresponsible and being activated by looking at thepicture.

The prestige of any science which is based onphysical technology like this is such that it's onlytoo easy to be seduced into thinking that it's theonly way to make major advances inunderstanding. It's easy to think that by looking atpictures like this, we are actually looking at thebrain-writing in which language, and indeedthought, is inscribed. But even if the resolution ofthe pictures gets to the point where we couldidentify each and every one of the nerve cellsinvolved in processing language, we still know solittle about language itself that we'd be unwise toregard these visual configurations as anything likean explanation. Because in order to explainsomething, we have to know exactly what it is wewant to explain. And that means that as long ashe's equipped with a strong-enough linguistictheory, someone who sits down and talks to apatient is quite likely to be doing just as goodscience as his colleague who x-rays the inside ofher head.

Well, I've got a pretty good picture of what yourlife is like.

Well, I feel I-- I feel, but I don't always say the proper things properly.

Well, you said quite a lot which makes sense tome. I must say I can understand where you came from.

I know, that's thoughts. I know sometimes theysell me, well, take slowly and tell me properly.Whereas I'm just, oh yeah, that's the way it is, sogets go. You know, that's the trouble. I-- I didn'ttake as I slewdly. Something when I couldn't hearanything at all here, and then gladually, hell me, Icould speak because I'd gone people out andhave hotel, just, I mean hotel first. And they, tosee people I couldn't spee much. It tooth it wasgradually, and now they've go up lots. But I can'twrite well of the words well enough.

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