The Language Instinct: How the Mind Creates Language (6 page)
Read The Language Instinct: How the Mind Creates Language Online
Authors: Steven Pinker
No one has yet located a language organ or a grammar gene, but the search is on. There are several kinds of neurological and genetic impairments that compromise language while sparing cognition and vice versa. One of them has been known for over a century, perhaps for millennia. When there is damage to certain circuits in the lower parts of the frontal lobe of the brain’s left hemisphere—say, from a stroke or bullet wound—the person often suffers from a syndrome called Broca’s aphasia. One of these victims, who eventually recovered his language ability, recalls the event, which he experienced with complete lucidity:
When I woke up I had a bit of a headache and thought I must have been sleeping with my right arm under me because it felt all pins-and-needly and numb and I couldn’t make it do what I wanted. I got out of bed but I couldn’t stand; as a matter of fact I actually fell on the floor because my right leg was too weak to take my weight. I called out to my wife in the next room and no sound came—I couldn’t speak…. I was astonished, horrified. I couldn’t believe that this was happening to me and I began to feel bewildered and frightened and then I suddenly realized that I must have had a stroke. In a way this rationalization made me feel somewhat relieved but not for long because I had always thought that the effects of a stroke were permanent in every case…. I found I could speak a little but even to me the words seemed wrong and not what I meant to say.
As this writer noted, most stroke victims are not as lucky. Mr. Ford was a Coast Guard radio operator when he suffered a stroke at the age of thirty-nine. The neuropsychologist Howard Gardner interviewed him three months later. Gardner asked him about his work before he entered the hospital.
“I’m a sig…no…man…uh, well,…again.” These words were emitted slowly, and with great effort. The sounds were not clearly articulated; each syllable was uttered harshly, explosively, in a throaty voice….
“Let me help you,” I interjected. “You were a signal…”
“A sig-nal man…right,” Ford completed my phrase triumphandy.
“Were you in the Coast Guard?”
“No, er, yes, yes…ship…Massachu…chusetts…Coast-guard…years.” He raised his hands twice, indicating the number “nineteen.”
“Oh, you were in the Coast Guard for nineteen years.”
“Oh…boy…right…right,” he replied.
“Why are you in the hospital, Mr. Ford?”
Ford looked at me a bit strangely, as if to say, Isn’t it patently obvious? He pointed to his paralyzed arm and said, “Arm no good,” then to his mouth and said, “Speech…can’t say…talk, you see.”
“What happened to you to make you lose your speech?”
“Head, fall, Jesus Christ, me no good, str, str…oh Jesus…stroke.”
“I see. Could you tell me, Mr. Ford, what you’ve been doing in the hospital?”
“Yes, sure. Me go, er, uh, P.T. nine o’cot, speech…two times…read…wr…ripe, er, rike, er, write…practice…get-ting better.”
“And have you been going home on weekends?”
“Why, yes…Thursday, er, er, er, no, er, Friday…Bar-ba-ra…wife…and, oh, car…drive…purnpike…you know…rest and…tee-vee.”
“Are you able to understand everything on television?”
“Oh, yes, yes…well…al-most.”
Obviously Mr. Ford had to struggle to get speech out, but his problems were not in controlling his vocal muscles. He could blow out a candle and clear his throat, and he was as linguistically hobbled when he wrote as when he spoke. Most of his handicaps centered around grammar itself. He omitted endings like
-ed
and
-s
and grammatical function words like
or, be
, and
the
, despite their high frequency in the language. When reading aloud, he skipped over the function words, though he successfully read content words like
bee
and
oar
that had the same sounds. He named objects and recognized their names extremely well. He understood questions when their gist could be deduced from their content words, such as “Does a stone float on water?” or “Do you use a hammer for cutting?,” but not one that requires grammatical analysis, like “The lion was killed by the tiger; which one is dead?”
Despite Mr. Ford’s grammatical impairment, he was clearly in command of his other faculties. Gardner notes: “He was alert, attentive, and fully aware of where he was and why he was there. Intellectual functions not closely tied to language, such as knowledge of right and left, ability to draw with the left (unpracticed) hand, to calculate, read maps, set clocks, make constructions, or carry out commands, were all preserved. His Intelligence Quotient in nonverbal areas was in the high average range.” Indeed, the dialogue shows that Mr. Ford, like many Broca’s aphasies, showed an acute understanding of his handicap.
Injuries in adulthood are not the only ways that the circuitry underlying language can be compromised. A few otherwise healthy children just fail to develop language on schedule. When they do begin to talk, they have difficulty articulating words, and though their articulation improves with age, the victims persist in a vareity of grammatical errors, often into adulthood. When obvious nonlinguistic causes are ruled out—cognitive disorders like retardation, perceptual disorders like deafness, and social disorders like autism—the children are given the accurate but not terribly helpful diagnostic label Specific Language Impairment (SLI).
Language therapists, who are often called upon to treat several members in a family, have long been under the impression that SLI is hereditary. Recent statistical studies show that the impression may be correct. SLI runs in families, and if one member of a set of identical twins has it, the odds are very high that the other will, too. Particularly dramatic evidence comes from one British family, the K’s, recently studied by the linguist Myrna Gopnik and several geneticists. The grandmother of the family is language-impaired. She has five adult children. One daughter is linguistically normal, as are this daughter’s children. The other four adults, like the grandmother, are impaired. Together these four had twenty-three children; of them, eleven were language-impaired, twelve were normal. The language-impaired children were randomly distributed among the families, the sexes, and the birth orders.
Of course, the mere fact that some behavioral pattern runs in families does not show that it is genetic. Recipes, accents, and lullabies run in families, but they have nothing to do with DNA. In this case, though, a genetic cause is plausible. If the cause were in the environment—poor nutrition, hearing the defective speech of an impaired parent or sibling, watching too much TV, lead contamination from old pipes, whatever—then why would the syndrome capriciously strike some family members while leaving their near age-mates (in one case, a fraternal twin) alone? In fact, the geneticists working with Gopnik noted that the pedigree suggests a trait controlled by a single dominant gene, just like pink flowers on Gregor Mendel’s pea plants.
What does this hypothetical gene do? It does not seem to impair overall intelligence; most of the afflicted family members score in the normal range in the nonverbal parts of IQ tests. (Indeed, Gopnik studied one unrelated child with the syndrome who routinely received the best grade in his mainstream math class.) It is their language that is impaired, but they are not like Broca’s aphasics; the impression is more of a tourist struggling in a foreign city. They speak somewhat slowly and deliberately, carefully planning what they will say and encouraging their interlocutors to come to their aid by completing sentences for them. They report that ordinary conversation is strenuous mental work and that when possible they avoid situations in which they must speak. Their speech contains frequent grammatical errors, such as misuse of pronouns and of suffixes like the plural and past tense:
It’s a flying finches, they are.
She remembered when she hurts herself the other day.
The neighbors phone the ambulance because the man fall off the tree.
They boys eat four cookies.
Carol is cry in the church.
In experimental tests they have difficulty with tasks that normal four-year-olds breeze through. A classic example is the
wug
-test, another demonstration that normal children do not learn language by imitating their parents. The testee is shown a line drawing of a birdlike creature and told that it is a
wug
. Then a picture of two of them is shown, and the child is told, “Now there are two of them; there are two _____.” Your typical four-year-old will blurt out
wugs
, but the language-impaired adult is stymied. One of the adults Gopnik studied laughed nervously and said, “Oh, dear, well carry on.” When pressed, she responded, “Wug…wugness, isn’t it? No. I see. You want to pair…pair it up. OK.” For the next animal,
zat
, she said, “Za…ka…za…zackle.” For the next,
sas
, she deduced that it must be “sasses.” Flushed with success, she proceeded to generalize too literally, converting
zoop
to “zoop-es” and
tob
to “tob-ye-es,” revealing that she hadn’t really grasped the English rule. Apparently the defective gene in this family somehow affects the development of the rules that normal children use unconsciously. The adults do their best to compensate by consciously reasoning the rules out, with predictably clumsy results.
Broca’s aphasia and SLI are cases where language is impaired and the rest of intelligence seems more or less intact. But this does not show that language is separate from intelligence. Perhaps language imposes greater demands on the brain than any other problem the mind has to solve. For the other problems, the brain can limp along at less than its full capacity; for language, all systems have to be one hundred percent. To clinch the case, we need to find the opposite dissociation, linguistic idiot savants—that is, people with good language and bad cognition.
Here is another interview, this one between a fourteen-year-old girl called Denyse and the late psycholinguist Richard Cromer; the interview was transcribed and analyzed by Cromer’s colleague Sigrid Lipka.
I like opening cards. I had a pile of post this morning and not one of them was a Christmas card. A bank statement I got this morning!
[A bank statement? I hope it was good news.]
No it wasn’t good news.
[Sounds like mine.]
I hate…, My mum works over at the, over on the ward and she said “not another bank statement.” I said “it’s the second one in two days.” And she said “Do you want me to go to the bank for you at lunchtime?” and I went “No, I’ll go this time and explain it myself.” I tell you what, my bank are awful. They’ve lost my bank book, you see, and I can’t find it anywhere. I belong to the TSB Bank and I’m thinking of changing my bank ’cause they’re so awful.
They keep, they keep losing…[someone comes in to bring some tea] Oh, isn’t that nice.
[Uhm. Very good.]
They’ve got the habit of doing that. They lose, they’ve lost my bank book twice, in a month, and I think I’ll scream. My mum went yesterday to the bank for me. She said “They’ve lost your bank book again.” I went “Can I scream?” and I went, she went “Yes, go on.” So I hollered. But it is annoying when they do things like that. TSB, Trustees aren’t…uh the best ones to be with actually. They’re hopeless.
I have seen Denyse on videotape, and she comes across as a loquacious, sophisticated conversationalist—all the more so, to American ears, because of her refined British accent. (
My bank are awful
, by the way, is grammatical in British, though not American, English.) It comes as a surprise to learn that the events she relates so earnestly are figments of her imagination. Denyse has no bank account, so she could not have received any statement in the mail, nor could her bank have lost her bankbook. Though she would talk about a joint bank account she shared with her boyfriend, she had no boyfriend, and obviously had only the most tenuous grasp of the concept “joint bank account” because she complained about the boyfriend taking money out of her side of the account. In other conversations Denyse would engage her listeners with lively tales about the wedding of her sister, her holiday in Scotland with a boy named Danny, and a happy airport reunion with a long-estranged father. But Denyse’s sister is unmarried, Denyse has never been to Scotland, she does not know anyone named Danny, and her father has never been away for any length of time. In fact, Denyse is severely retarded. She never learned to read or write and cannot handle money or any of the other demands of everyday functioning.
Denyse was born with spina bifida (“split spine”) a malformation of the vertebrae that leaves the spinal cord unprotected. Spina bifida often results in hydrocephalus, an increase in pressure in the cerebrospinal fluid filling the ventricles (large cavities) of the brain, distending the brain from within. For reasons no one understands, hydrocephalic children occasionally end up like Denyse, significantly retarded but with unimpaired—indeed, overdeveloped—language skills. (Perhaps the ballooning ventricles crush much of the brain tissue necessary for everyday intelligence but leave intact some other portions that can develop language circuitry.) The various technical terms for the condition include “cocktail party conversation,” “chatterbox syndrome,” and “blathering.”