I Can Hear You Whisper (9 page)

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Fletcher wasn't the only one whose work was inspired by the telephone. In the 1920s, just as the Bell Labs team was investigating the properties of speech and hearing, Hungarian scientist Georg von Békésy began zeroing in on just one component of that chain: the inner ear. After completing his PhD in physics in 1923 at the University of Budapest, Békésy took a job at the Telephone System Laboratory at the Hungarian Post Office, which maintained the country's telephone, telegraph, and radio lines. “After World War I, [it was] the only place in Hungary that had some scientific instruments left and was willing to let me use them,” he said later. His job was to determine whether making changes in the telephones themselves or in the cables led to greater improvements in telephone quality. His engineering colleagues wanted to know “which improvements the ear would appreciate.” At first, Békésy turned to library books for answers. But he soon realized that while a lot was known about the anatomy of the ear, very little was understood about its physiology, how it actually worked. He began studying the function of the inner ear, and the subject became his life's work.

Békésy wanted to see the cochlea in action, and I do mean “see.” He collected an assembly line of temporal bones from cadavers at a nearby hospital and kept them in rotation on his workbench. First, he made models of the cochlea based on his samples, then he began to do experiments with the human cochlea. Using a microscope that he designed himself to send strobes of multicolored light onto the inner ear, he watched the basilar membrane, the cellophane-like ribbon that runs the length of the cochlea, as it responded to sound. The setup he rigged allowed him to see a sound wave ripple from one end of the basilar membrane to the other. He also identified critical properties of the membrane, that it was stiff at one end and more flexible at the other. Although the idea that different places on the basilar membrane responded to different frequencies had already been posited, Békésy was the first to see that response with his own eyes: The displacement of one part of the membrane was greater than the rest, depending on the frequency of the tone. His discovery was called
Békésy's traveling wave.

After World War II, not wanting to live in what had become Communist Hungary, Békésy continued his work first at the Karolinska Institute in Sweden and then at Harvard. A loner by nature, he never taught a student or collaborated with anyone. Nevertheless, he was awarded the Nobel Prize in Physiology or Medicine in 1961 for his work on “the physical mechanism of stimulation within the cochlea.” Nobel Prize or no, we know today that there are at least two fundamental problems with Békésy's work. One is that his subjects were dead. The auditory system is a living thing and responds more subtly when alive than dead. Secondly, in order to get any response from the cochlea of a cadaver, he had to generate noise that was loud enough (134 dB) to wake the dead, so to speak. As a result, the broad response Békésy saw didn't accurately reflect the finesse of the basilar membrane. Despite its limitations, Békésy's traveling wave represented an important advance. In a recent appreciation of his work, Peter Dallos and Barbara Canlon wrote, “
This space-time pattern of vibration of the cochlea's basilar membrane forms the basis of . . . our ability to appreciate the auditory world around us: to process signals, to communicate orally, to listen to music.”

Békésy had narrow shoulders, but in the best scientific tradition, many who came later stood upon them. Back at Bell Labs, in the 1950s, later generations of researchers used Békésy's work to build an artificial basilar membrane and then, in the 1970s, to devise computer models of its function, all of which would prove critical in the digital speech processing that lay ahead.

Jean Marc Gaspard Itard had been dead wrong about the possibilities of science.

T
he day after Alex got his hearing aids, he and I went on an errand. As I unstrapped him from his car seat, I discovered he had yanked out both earmolds. At least they were still connected to the safety clip—his had a plastic whale to attach to his shirt and long braided cords like those for sunglasses. But when I tried to reinsert the earmolds, everything looked wrong. Alex had twisted them out of position. I stood there with the tangle of nubby plastic and blue cord in my hand and realized that in spite of the lesson Jessica had given me, I had absolutely no idea how to restore order—which was left, which was right, whether they were backward or forward, or how to begin to put them into his ears.

“Well, shit,” I said out loud. “Shit, shit, shit.”

Alex smiled. At least I was free to curse in front of him. The word “shit” had high-frequency “sh” and “t” sounds that he would never hear. After the frustration of weeks of uncertainty and disequilibrium . . . here I was, on the sidewalk, lost.

Fortunately, we were about to visit the preschool program at the Auditory/Oral School in Brooklyn, and I'd been given a fresh reminder of the benefits of an environment where people were familiar with what it is to be deaf or hard of hearing. It was just dawning on me that one of my new roles was going to be serving as Alex's IT Help Desk, and I was sorely unprepared.

Piling the tangled equipment onto the top of his stroller, I made my way to the front door.

“Um, we need a little help putting these back in,” I confessed when I got inside. “We're new at this.”

The director of the school smiled and picked up the hearing aids. “See how the mold curves?” she said, indicating the way the plastic followed the line of Alex's ear canal. Gently, she pulled his earlobe back and popped one aid into position. Then she did the same on the other side. Ten seconds and it was done.

In making choices about education and communication in the deaf and hard-of-hearing world, people talk about “outcomes.” Since Alex had usable hearing and our desired outcome was talking and listening, we had decided to look at oral programs. These were the “option” schools my friend Karen had been talking about a few weeks earlier. All would provide explicit language instruction to get Alex beyond “mama,” “dada,” hello,” and “up.”

I had thought Karen was out of her mind to suggest that a two-year-old child might travel an hour from home for school. The additional complication of having to get two other children, then seven and four, to and from school near our house stymied me. But Mark is good at making the impossible seem possible, and far less worried than I am about spending money to solve problems. He immediately threw out solutions: babysitters, car services, an Ecuadorean taxi driver we knew who might be willing to help, and so on. Soon we had a plan. I wasn't willing to put Alex on the school bus yet, so we split the week between me and a pair of babysitters and ultimately chose Clarke, a Manhattan satellite of the school founded by Mabel Hubbard's father, in part because it was reachable by subway. There, Alex would spend every morning bathed in words and language.

In the same way that an aspiring athlete has to train and strengthen muscles, Alex had to practice learning to talk.
Speech production is a motor skill like kicking a ball or picking up a raisin. We don't think of it that way because it doesn't usually make us sweat or even require much effort once we've mastered it, but a babbling baby is training her vocal system to produce the sounds she's been hearing through the first months of life. The attempts are tentative at first. She knows she's getting close when the adults in her world get excited about the noises she makes. The sounds get more and more confident until they come out as words. Alex had missed all of that.

Sound is produced by vibrations and columns of air. Our bodies provide both. In all spoken languages, the fundamental speech sounds are similar because the range of possibilities has physical limits. Words begin in the lungs, which serve both as a store of air and as a source of energy. That air is pushed out of the lungs and, on its way to being transformed into the sounds of speech, it passes along the conveyor belt of our vocal systems.

Lodged in the top and front of the trachea, the larynx is made mostly of cartilage, including the thyroid at the front that forms the Adam's apple. Inside the larynx are the vocal cords. They're sometimes called the vocal folds, and that's a more accurate term, as there is nothing cordlike about the vocal cords. They are pieces of folded ligament that meet to make a V-shaped slit (the glottis) that closes to stop air or opens to let it pass through. To produce the “d” in “idiot,” for example, air is stopped entirely. For soft sounds like the “f” of “farm” and the “s” in “sunny,” the vocal cords are completely open, and the feathery or hissing sounds can go on indefinitely, which is why those consonants are described as “continuant.” And why they had so much less going on in the picture of “farmers” created by the Bell Labs oscillograph. When the vocal cords rapidly open and close, they create a vibration that allows us to make vowels and the sounds of “voiced consonants” such as “v,” “z,” “b,” “d,” and “g.” If you watch the changing shape of your lips when you make a “p” sound, an “o,” or an “f,” you can get an idea of the movement of the vocal cords inside your throat, and you can feel the difference between voiced and unvoiced sounds if you make a “zzz” and then a “sss” with a finger resting on your Adam's apple.

To whisper, we keep our vocal cords in the same middle position as for the “h” of “hill.” The louder the whisper we want to make, the closer together we bring our vocal cords, so that the word “hill” spoken in a loud whisper results in more air leaving your lips than saying it in a normal voice.

Leaving the lungs and vocal cords as somewhat amorphous buzzes and whooshes, the flow of air is further refined—stopped and restarted, pushed and pulled, narrowed or flattened—by the tuning we do in our mouths when we vary the shape and relative position of the palate, tongue, teeth, and lips. When speech pathologists talk of plosives or fricatives, for instance, they are describing what we have to do in this last stage of the conveyor belt. The plosives (“p,” “b,” “t,” etc.) require us to block the flow of air somewhere along the way, usually in the mouth. The fricatives (“s,” “f,” “sh,” etc.) are made by narrowing the air flow to form turbulence. To form the liquids (“r” and “l”) we raise the tip of the tongue and keep the mouth a bit constricted. “M,” “n,” and “ng” are nasals; “w” and “y” are semivowels. Speech sounds are further identified by place of articulation—labial (lips) or dental (teeth), for example. So a “p” is an unvoiced labial plosive, and a “th” is a voiced dental fricative. Like the Linnaean system of biological classification into kingdom, phylum, class, and so on, this way of organizing elementary features was a breakthrough when it was invented in the 1930s because it captures all of the speech sounds of the world's languages.

All of this matters when you're learning to talk because you have to know how to form the sounds you want to make. Most of us can go our whole lives blissfully ignorant of all the unvoiced labial plosives we produce in a day. But we had to learn, too. As newborns, we had a vocal tract that was not yet capable of the fine motor skills necessary for speech. An infant's larynx is too high in the throat, and the tongue fills the mouth. But the system matures quickly, and usually by four months, babies begin playing around, babbling, with their teeth and tongues. By trial and error, most get there naturally, though some sounds are harder to master than others. Our son Matthew had trouble with “r's” and “l's” until he was six. Words like “girl” and “earth” were almost unintelligible, which wasn't all that uncommon. “R” and “l” tend to be among the last phonetic sounds that children master.

Without hearing aids or a cochlear implant, someone who is profoundly deaf can not only not hear others, he also cannot hear himself. The only way for him to form spoken words is to memorize where exactly to put his tongue, how to form his lips, and what it feels like if he touches his larynx for each separate sound.

For Alex, on the other hand, his new hearing aids were now bringing him information about sound he hadn't had access to before. Relying on residual hearing, hearing aids amplify sound to bring as much as possible into the range necessary for understanding speech. They had come a very long way since Alfred duPont's desk-size boardroom set. Today, they are digital; audiologists can program them very precisely to an individual's hearing loss. It was as if we had pushed the reset button on learning language, but with a lot of ground to make up.

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Perched on a wooden stool in the hallway of the Clarke School on a Monday morning in April, just after Alex's second birthday, I watched through an observation window as he worked with a speech language pathologist named Alison for the first time. A headset allowed me to listen as well.

“Choo choo,” Alison said as she rolled a wooden engine along a piece of track.

“Push,” she said, showing him how she moved the train. “Push.”

She blew a bubble. “Pop!”

She held her hand over his and touched his chest. “Me,” she said, tapping his chest with his own little hand, “me.”

Alex, watchful and shy, blew some bubbles, but he didn't say “pop” or “me.” Instead, he pointed to a toy farm on her shelf that had caught his eye. When Alison held the cow to her face and said “moo,” Alex didn't imitate her. But he laughed and pointed to the next animal.

Though he enjoyed the animals, Alex was anxious and tearful in his first few weeks at Clarke. Each week, his teachers of the deaf and therapists sent home notes on his progress.

“Limited verbal output today; still a bit fearful during transitions,” his teacher noted in the second week.

“Alex cried upon separation from his mother . . . ,” the next day's note read. “He repeated ‘pat-pat-pat' and ‘rooooll' during play with Play-Doh; when he saw his mother through the window/door, he fell to the floor and cried.”

Note to self: Stay well back from the window.

The next week was better: He “actively stomped his feet” for “If You're Happy and You Know It” and “enjoyed pasting pictures to the construction paper.” On the other hand, he “monopolized the glue sticks.”

Play never sounded so un-fun. But if the clinical detail effaced the joy, I knew there was a point. For these children, no word could be taken for granted. Everything had to be introduced and repeated. The notes came with lesson plans for every week, listing vocabulary to be targeted and all the themed activities that would be used to teach the new words. As for all children, one of the goals of preschool was to learn how to get along with others. A few of Alex's new classmates had issues beyond hearing: behavioral problems, or motor skill delays. Glue sticks notwithstanding, I was relieved that there was no sign in Alex of some of the disruptive or asocial behavior I saw in some of the other children.

Rather, Alex seemed to be the kind of kid who needed to learn to stick up for himself. He had to be taught to say “me” or “no” if a classmate took the truck he was using or tried to steal his Goldfish.

Beyond his behavior, the daily reports teemed with approximations, verbalizations, modeling, mouthing, gesturing, cuing, and so on. It took me a little studying to learn how to decode the notes.

“Alex assumed articulatory posture for /w/ sound without sound emission. . . .” Translation: He mouthed the “wah, wah, wah” of the babies crying in the “Wheels on the Bus” song.

“Alex approximated production of ‘cut cut cut' and ‘knock knock knock' imitating clinician's productions with accuracy in number of repetitions and syllable length.” He said (probably) “cu, cu, cu” and “na, na, na.”

By June, he was combining “actions with labels”: “wash baby,” “come doggie,” “go car.”

By August, according to a list I kept, he had close to a hundred words, although most were approximations. He called himself “Ala.” He could handle Mama, Dada, and Matty, but he had trouble with “j” and “s,” so big brother Jake and his babysitters, Jacky and Sean, who took turns taking him to school, all got “d” at the front of their names: Dake, Dacky, and Dawn. Other new words and phrases were painstakingly added:

Eyes, nose, hat, milk . . .

Up, down, shoes, juice . . .

Water, boat, bike, away . . .

Uh-oh, more, all done . . .

Stop it. No touch. I love you.

Because he couldn't hear high frequencies, he left out all “k,” “t,” and “s” sounds. He said “ow” for “cow” and “um” for “come.”

He was still very quiet and observant. Mostly he was compliant, and if he was frustrated, he didn't show it. So it came as a surprise one day when he threw his hearing aids into the street as he rolled along in his stroller. They were nearly run over by a bus.

“I'm relieved to hear it,” said one of his teachers when I told her.

“What?!”

“It's developmentally appropriate,” she said.

He was two after all.

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Alex had an audiogram. He had hearing aids. He was in a specialized school. He was making progress, and the flurry of activity had apparently slowed into routine. One question remained: Why had this happened?

Neither Mark nor I knew of anyone in either of our families who had been deaf or hard of hearing as a child. Nothing dramatic had happened during my pregnancy: no infections that we knew of, no trauma, no worrisome blood tests or ultrasounds. The only drama had come at the end, when Alex arrived four weeks earlier than expected, which doctors classified as preterm but not premature. I couldn't help but wonder if I was responsible somehow, even though the rational part of my brain knew that was unlikely and that such thinking was counterproductive.