I Can Hear You Whisper (4 page)

Hearing loss doesn't just make the world quieter, it garbles it. When the ear can't tune sounds as sharply, they blur into one another. To someone with some low-frequency hearing, speech sounds dull and muffled, so that even what is audible is hard to understand.

This explained why it had taken so long to detect Alex's loss. He had been hearing some things but not others, responding to some things but not others. What he did hear, he didn't hear clearly. The fluid had intensified the problem but also made it obvious, allowing us to act. A profoundly deaf child is far easier to identify than one who is hard of hearing. Alex's hearing loss also suggested an explanation for the delays in his gross motor skills as a baby; hearing and balance are both centered in the inner ear. Damage sometimes, though not always, encompasses both systems.

Uncovering Alex's hearing loss had been like falling downstairs in slow motion. It dragged on, with information coming in fits and starts. Now, perhaps, we had come to rest, could catch our breath, take stock, and start climbing back up the steps.

With some usable hearing, and hearing aids, there was every reason to think that Alex could achieve spoken language. When it comes to learning to speak, the difference between those who are profoundly deaf from birth or before learning language and those who are hard of hearing has historically been stark.
In one state's survey, only 25 percent of children who started out profoundly deaf were able to speak intelligibly by the age of five or six. The statistic was reversed for those with mild to severe hearing loss: 75 percent could be understood when they talked.

Karen had been right about the audiogram. Our decision hinged on it. Since Alex appeared to be able to hear most speech using hearing aids, and he would be right in the speech banana for everything but the highest frequencies, we decided to make speaking and listening our immediate goal and to learn ASL later as a second language.

Sound became essential, the all-important sensation on which everything depended. Like a musician who trains to play by ear, to identify if a note is flat, to pick out oboes over the clarinets, Alex was going to need to practice, practice, practice, and practice his listening some more. He had a lot of catching up to do. He was nearly two and he could say only “mama,” “dada,” “hello,” and “up.”

 • • • 

“We figured out why Alex isn't talking,” I explained to Jake and Matty, who were then six and three. “He can't hear very well.” Although they'd been caught up in their school lives—in first grade and preschool respectively—they had certainly noticed that Alex and I had been spending an awful lot of time going to the doctor and the audiologist. And they had periodically complained.

Even before that, they hadn't been overly thrilled at the prospect of another baby competing for attention. Matthew had been offended at having his role as youngest in the family usurped. Only nineteen months old when Alex was born, he'd thrown a spectacular tantrum while visiting us in the hospital and then mostly ignored Alex in his first year of life, as if that might just make him go away. Jake had already been toughened up by one new brother's arrival. “Can you be my mommy and daddy be Matty's mommy?” he'd asked me plaintively the night Matthew came home from the hospital. He was more accepting of Alex but still capable of an occasional fit of pique over the time I had to devote to the baby.

So I was relieved and gratified when the big boys reacted to my announcement by dropping to the floor, leaning in close on either side of Alex, and hollering: “We love you, Alex!” Then all three grinned. Alex loved being the center of attention; the others figured they'd just been given license to yell in the house.

I
n any one of the
nearly seven thousand languages of the world, babies begin to communicate along a roughly similar schedule.
Most begin to talk around their first birthday. They put words together in simple sentences like “eat cookie” at about a year and a half. They pick up as many as ten words a day in their twos and, by the time they're three, most are speaking in sentences and know over one thousand words. For English speakers, there are only another fifty thousand more to learn by adulthood.

How do children do it? Here is where the answers get harder. Learning language is “
doubtless the greatest intellectual feat any one of us is ever required to perform,” said Leonard Bloomfield, a major linguist of the early twentieth century. It's so difficult, computers still can't do it; so far, they have been successfully programmed to fluently understand only one speaker at a time. Yet babies and young children master this enormous task so naturally, few of us even remember making the effort.
From Saint Augustine to Charles Darwin to Noam Chomsky to modern-day linguists, a subset of whom are also neuroscientists, a long line of thinkers have pondered the question. Today's views on how babies accomplish the feat owe much to the ideas that Chomsky put forward in the late 1950s, when he burst onto the language scene and spearheaded the cognitive revolution in linguistics and psychology.

Up to that point, the behaviorists, led by B. F. Skinner, held sway. Expanding from Pavlov's famous experiments in which dogs could be made to salivate at the ringing of a bell, the behaviorists maintained that animals and children were essentially blank slates and could be conditioned to do almost anything, provided the stimuli and setting were right. Language, argued Skinner, was just another behavior, a “verbal behavior.”
Chomsky disagreed and wrote a devastating review of Skinner's work.

Chomsky's main idea directly contradicted the behaviorists and was hugely controversial at the time. Some aspects of it are still debated—even by Chomsky himself—but many of its tenets are widely accepted today. He argued that babies arrive in the world with an innate ability for language. Nature, said Chomsky, has provided children with a surprising level of knowledge about language that they can't have had time to learn—“the language instinct,” Steven Pinker called it in his bestselling 1994 book of that name. Chomsky believed children had a native ability to deploy what he called “universal grammar,” referring not to the details of parsing sentences but rather to an unconscious, tacit sense of some basic universal principles of language—so basic they apply whether the child will grow up to speak English, Swahili, or Chinese. For example: All languages have consonants and vowels, they have nouns and verbs, and they have pitches, contours, and intonations; phrases, not words, are the building blocks of sentences, and the rules governing how one can move those phrases around are the same.
Universal grammar explained how children could know that Chomsky's famous nonsensical sentence—“Colorless green ideas sleep furiously”—was grammatically correct, while the same words rearranged—“Furiously sleep ideas green colorless”—created a sentence that was gobbledygook, neither grammatical nor understandable.

Even if the ability to learn language is innate, we do not all begin speaking equally well. Language literature is populated with examples of “wild children,” such as
Victor of Aveyron, who lived alone in the woods of eighteenth-century France until he was about twelve, or
Genie, a California victim of horrific abuse who was discovered in 1970 after she had been kept locked in a bedroom and tied to the furniture for the first fourteen years of her life. These unfortunate children had almost no exposure to language, among other things, and provided an unusual opportunity for study. Neither ever achieved normal language skills. The fact that deaf babies do not automatically learn to talk also tells us that the skill is not purely innate. Yet if a deaf baby's parents are fluent signers, he or she becomes a native user of sign language, which adheres to universal grammar, and the baby will follow the same path to fluency with visual language as hearing babies do with spoken language. So while speech may not be innate, certain patterns of language learning seem to be.

“Language is a super-interesting learning problem,” neuroscientist Elissa Newport told me as we sat in her new, somewhat bare office at Georgetown University Medical Center. Newport specializes in the acquisition of language. For twenty-three years, she was at the University of Rochester, the last twelve as chair of the Department of Brain and Cognitive Sciences. When I met her, she had just moved to Washington to head a new center for brain plasticity and recovery, where she is studying how young children who suffer a certain kind of stroke recover their language. Her straightforward, no-nonsense style is evident in everything from her short hair to her scientific approach. “We know that languages of the world have a certain type of organization that you don't see in any other species' communication system, and languages of the world have a lot of interesting profound similarities to one another. So there's a very interesting problem to explain: How did we get languages like that, and how do you learn them, and what kind of brain mechanisms are required to do that?”

When Alex was turning two, I hadn't yet realized how important the question of brain mechanisms would be. I was fixated on the second of Newport's questions: How do you learn language? I sought out Newport because I wanted to understand not just what Alex couldn't do but also what other children could do and why. Following the lead of scientists, I knew I needed to understand what was typical in order to better make sense of what was atypical. What I found was worrisome—for what it was clear Alex didn't get as a baby—but also a little bit reassuring, as I began to appreciate that he had managed to learn some important things about language with very little help from sound.

One fact scientists agree on isn't surprising anymore: To learn a language, it's best to start young. “We certainly learn languages as adults but not to the same degree of proficiency,” says Newport, “and there's much more variation among individuals as we get older.” To say that children are “better” is too simplistic. “Young children don't really learn faster or better,” says Newport. “They learn more slowly. It's kind of tortoise and hare. If you look at people who move to a new country, adults are generally faster, they just don't get as far. They do it differently and they don't end up as good.”

Newport gave me an intriguing example. She has spent much of the past ten years making up what she calls “
miniature languages.” In different studies, the same eight verbs and fifteen nouns carry different meanings. So “kleidum” means “drag” in one instance and “head-butt” in another (one can only imagine the story that language will tell). Words like “tombat,” “nagid,” and “melnawg” might mean “singer” or “baby carriage” or “shopping cart.” Newport teaches these limited strings of invented words to babies, children, and adults in her laboratory using pictures and videos. They are then tested on comprehension and production (naturally, the babies aren't expected to speak). Over the course of as few as five days, Newport uses behavioral tests and brain imaging to watch language acquisition unfold—the whole endeavor is like applying time-lapse photography to learning. (It should be noted that these are all second languages for the subjects.)

On the question of the differences between learning as a child and as an adult, she told me that in a recent series of studies, she added some inconsistencies, or errors, to the miniature languages. Five- and six-year-old children acquired the regular parts of the language, not the errors. Adults reproduced more inconsistencies. This is an example of the less-is-more hypothesis, argues Newport. “Kids are more cognitively limited. For certain kinds of tasks, that may be an advantage. They don't get it all at once. They actually can't acquire all the little irregular things about languages, all the details. They get the more consistent, regular parts. That produces a staged type of learning where you get the big patterns first and then you get the little details much later. Adults get all the details right at the start, and they never get the big patterns.”

Her study reminded me of a moment when Matthew, our middle son, was about four—certainly, he had not yet learned to read. Standing in the kitchen one Saturday, Mark posed a riddle he had just read: “Mary's father has five daughters: Nana, Nene, Nini, and Nono. What's the fifth daughter's name?” The name Nunu was on the tip of my tongue, when Matthew piped up. “Mary,” he said, and gazed at Mark and me as if nothing could be more obvious. I stared back at him and then realized that he was right.

“How did you know that?” I asked. Then I turned to Mark. “He's brilliant!”

No, I realized later, he was simply four and had not yet learned that if A, E, I, and O are presented in sequence, it's a very good bet that U will follow. When Mark told the joke, I knew too much about vowels, and Matthew, who was a charming, talkative, outgoing child, but not necessarily brilliant, knew just the right amount, which is to say, very little.

“That's exactly the same thing,” agreed Newport when I told her the story. Language learning is really a matter of learning patterns. “By mechanisms we don't totally understand, we store an incredible wealth of quantitative details about how sounds combine,” says Newport. “That's basically what learning a language is about. You do it with the sounds of your language. You do it with the meanings and what people are referring to. You do it with the sequences in which words occur. You don't just memorize all the sound sequences. You somehow compute. You keep track of things that are very frequent combinations, frequent categories.”

For spoken languages, you do all of that by listening. “The first year of life is largely a silent rehearsal,” wrote linguist Charles Yang in his book
The Infinite Gift: How Children Learn and Unlearn the Languages of the World
. The process starts before birth. Around six months of gestation, expectant mothers begin to feel the baby kick in response to loud noises. Bathed in amniotic fluid, the fetus can't generally make out words, just as you can't if you put your head underwater, much as you might have tried in the pool as a child. What a baby in utero does hear, over the low-frequency sounds of his mother's blood flowing through her body and her steady heartbeat, is what linguists call prosody, the rhythm and contours of the mother's native language. Babies hear enough of it to recognize and prefer their mother's voice once they are born.

How much there is to listen to in the first months and years of life has been shown to have a powerful effect on language ability or lack thereof. A landmark 1995 study by Betty Hart and Todd Risley showed this most starkly.
Hart and Risley had been studying early education for many years, even before Head Start was created. No matter how many creative ways they developed to bolster language in their programs, they were perplexed by the persistent difference in vocabulary growth between middle-class children and poorer children. Field trips, directed experiences, and discussions, all of it was ineffective.

“We began to ask what went on before we ever saw these children, because they started in preschool at age four,” Risley once explained in an interview. A little basic math revealed that if children were in preschool for a total of sixteen hours from Monday to Friday, they were awake for at least another sixty to seventy hours in a week. That begged the question of what happened at home. Hart and Risley decided to look at “what's going on in children before we ever see them in preschool, before they're four, while they're learning to talk,” as Risley put it. Over two and a half years, beginning when the children were nine months old, they sent observers into forty-two families in Kansas City for one hour every month to record every word that was said between parent and child. The families represented the entire socioeconomic spectrum from white-collar educated professionals through to parents on welfare.

What they found was so surprising Risley called it a “discovery,” not just a result. They had expected that the content of the language was most important. Instead, the most significant and fundamental factor was a massive difference in the amount of talking, the sheer volume of words that some children heard compared to others. The children of educated professional parents tended to hear as many as 2,100 words per hour. Those with uneducated parents on welfare heard 600. The average child heard 1,500 words an hour. Extrapolating those numbers to a year's worth of listening, Hart and Risley calculated that children with the most talkative parents had heard forty-eight million words by the time they were four. Those at the other end of the spectrum had heard a fraction of that, only thirteen million words—a gap of thirty-five million words.

Secondly, Hart and Risley did find what they expected: There were qualitative differences in the language the children heard, and those did matter. All parents used a certain amount of similar baseline vocabulary to instruct and inform children: “Stop that,” “Hold out your hands,” etc. Subtracting that kind of talk, which Risley calls “the business language” of parenthood, left very little conversation in the quietest homes. But talkative parents engaged in what Risley called “language dancing.” “The talkative parents are taking extra turns, responding to what the child just said and did, and elaborating on it, caring.”

Together, the amount of words and the quality of the “extra talk” had a direct, strong effect on the child. By the time they were three, children who had heard more words and more interesting talk had higher IQs and larger vocabularies. When Hart and Risley tested the children again at nine, the effect was still clear: The difference in early language exposure accounted for differences in vocabulary size and IQ. In fact, early language exposure canceled out socioeconomics or race. In the cases where a poorer parent talked a lot to a child, the child did fine; and if a professional parent did not talk to a child, the child struggled. As the children moved through elementary school, the differences had academic repercussions.