Thumbs, Toes, and Tears Page 9
Some scientists have speculated that the first proto-word/gesture might have been a pointing index finger that said, simply, “there.” Human toddlers spontaneously develop this ability at about the time they start to use their first words, around the age of fourteen months, the age, strangely enough, when a child attains a Homo erectus–size brain. In his book The Hand, neurologist Frank Wilson points out that cognitive and developmental psychologists agree that pointing in children is a “gesture of intentionality” that separates us from chimpanzees and is a unique milestone in human cognition. Chimpanzees do not spontaneously point with their index fingers, and they can’t be trained to use them (at least not with any knowledge of what it means).16,17
H. erectus’s miming wouldn’t in some ways have been very different from the case of the habiline father “explaining” to his daughter how to fashion a flint knife simply by showing her the process. If chimp behavior is any indication, even by the time Homo habilis emerged our mirror neurons would have been plenty well equipped to make the connection between a mimed action and the idea of the actual thing. And this would have been even truer when the “devastatingly clever” H. erectus showed up on the scene.
Over time, with so many thoughts to share and threats to make and information to express, body language and facial expressions might simply have fallen short of communicating all of the increasingly detailed information H. erectus’s brain was generating. Gestures representing vital but easily expressed information might have been central to better representing a large predator or food or drink. And in time these gestures might have been adopted throughout the troop to mean the same thing to everyone.18 Eventually, perhaps, random mimes began to evolve into more complex forms of communication—the first crack at a language, complete with a rudimentary syntax.
The problem with these theories is that they are difficult to prove. There are no fossilized artifacts that can shed light on how H. erectus learned to share his thoughts and feelings. Fortunately, however, some interesting theories have arisen out of the behavior of children.
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Child psychologists (and most parents) know that even at eight months of age, a baby’s thought processes are extremely sophisticated. They clearly have things they want to say and needs they want to express, but the shape of an infant’s throat, and her immature brain anatomy and nervous systems prevent her from actually using words.19,f
Toddlers, however, are perfectly capable of gesturing. Waving bye-bye is the best-known universal example. New studies have recently revealed that with a little help, this natural ability to communicate with a gesture can grow far more sophisticated than originally thought.20
In the 1990s a researcher named Joseph Garcia noticed that healthy, hearing babies born to deaf parents who communicate using American Sign Language (ASL) began to talk much sooner than the children of hearing parents. The interesting thing was that they weren’t speaking with their voices, they were speaking with their hands, just like their parents!
In subsequent studies Garcia also found that these infants would spontaneously sign that they were hungry, thirsty, or had a wet diaper as many as eight months before they were capable of actually saying a single word. This meant that the children’s brains were developed enough to talk, but they had to do it with their hands because they couldn’t do it using their throats.
At about the same time that Garcia was noticing this, Linda Acredolo at the University of California at Davis and Susan W. Goodwyn of California State University at Stanislaus also found that infants could communicate by hand gesture at eight months.21 Acredolo concluded that some form of gesturing is second nature for most children. “It’s just that people haven’t paid attention, and parents are so focused on words that they don’t see this as something to be encouraged.”
Just as toddlers can imitate the gestures for “Itsy Bitsy Spider” or sniff a flower and then use that one sniffing gesture to indicate the experience of sniffing any flower, they also can learn to associate gestures with a need, a thing, or a concept. In one study a little girl started with simple signed words such as “milk” and “more,” but within months was communicating far more complex ideas. During a visit to an aquarium when she was ten months old, she was watching penguins swim and signed “fish” to her mother. Her mother corrected her, and signed “bird.” That confused the girl, who again made the sign for “fish.” Then her mother signed “bird” plus “swimming.” That her daughter understood. Just two months later, the same girl picked up a feather lying on the ground and signed “bird hair,” an indication that she was now capable of combining two separate, previously learned concepts into an entirely new idea.
The work of Garcia, Acredolo, and Goodwyn all show that once exposed to signing, children take to it naturally because at this stage of their lives their hands are far more facile than their throats and mouths. As Elizabeth Bates, a pioneer in the field, put it, it is simpler to “imitate and reproduce something with a great big fat hand [than] the mini, delicate hundreds of muscles that control the tongue.”22 In other words, we don’t speak at this early age not because we don’t have the brainpower to think up ideas we want to express, but because we don’t have the properly developed neural pathways, throats, lungs, and tongues needed to say words.
Acredolo’s study even revealed that children who used gestures to communicate before they learned to speak developed IQs later in life as many as twelve points higher than children who didn’t sign in infancy. That indicates that the earlier children can share what is on their minds, the better they later grasp deeper intellectual concepts.23
Whatever the long-term benefits, the beauty of learning to communicate by gesture at this young age seems to have been that both parents and children became happier. One mother reported that when she started to sign with her eleven-month-old son, the noise level in the house dropped dramatically—not because they were silently signing but because her son wasn’t nearly as frustrated as he had been when his screaming and crying failed to make his point.
In fact, all three researchers found that toddlers often take rapidly to gesture because they are frustrated and can’t tell their caregivers what they want. Grimacing faces, twisting torsos, and outright bawling simply aren’t specific enough tools for a ten-month-old to say, “I’m hungry. I’m wet. This hurts. I want my bubby.” Gesture, however, accomplished the job beautifully, once babies learned the basics.
If a toddler can gesture symbolically to share what’s on her mind, could Homo erectus have done the same, especially given the survival pressures he was facing? He had the manual dexterity, the mirror neurons, and the social and practical needs. And he had a brain approximately the size of a toddler. This doesn’t mean that H. erectus had attained a human toddler’s intelligence—some aspects of brain architecture were certainly different—but it is possible that their general perceptions of the world were comparable. And both had strong reasons to communicate, even if they couldn’t use words to do it.
These haven’t been the only studies that reveal unexpected connections between gesture and language. A few years ago Laura Ann Pettito, a developmental psychologist at Dartmouth College, and her colleagues made a remarkable discovery when they were studying the babbling that all children do beginning at about the age of seven months.
Most scientists long ago concluded that the ba’s and blah’s and da’s, the raspberries, and endless trilling and slurping toddlers do at this age mark the earliest stages of an infant’s efforts to master the rhythmic, singsong sound patterns that lead to phonemes, words, and, eventually, sentences—the building blocks of language.
What made Pettito’s experiments unique is that she, like Joseph Garcia, worked with babies whose parents didn’t use words, but instead communicated in ASL. Her study focused on two groups of three babies each. The first group’s parents spoke and heard normally. But the second group was made up of the children of deaf parents who used ASL. In both cases, all the children could hear norm
ally.
As expected, each of the two groups began babbling at about seven months of age. But Pettito uncovered some peculiar behavior among the children of deaf parents: they were babbling with their hands as well as their mouths.24 Pettito’s team concluded this meant that the language patterns that the brain locks in during infancy are not exclusively related to sound. There are deeper rhythms the brain is grasping and reworking. Apparently if the child is exposed to spoken language, then he expresses those rhythms with sound, but if he is mostly exposed to sign language, then he expresses them with his hands.25
Hand babbling makes no more sense than the noises most talking babies make with their mouths; nevertheless, Pettito says, it represents a distinct effort to get a handle on the underlying rhythms of language, verbal or otherwise.26
Brain-scanning technologies have also recently revealed that Broca’s and Wernicke’s areas, the two parts of the human brain most directly involved in generating and understanding language, are as deeply involved in processing gestural language as they are in processing the spoken word.27 Stroke victims often suffer forms of aphasia that can destroy their ability to speak sensibly or to understand speech spoken to them. Most victims of Broca’s aphasia speak in gibberish, even though in their minds they think they are speaking with absolute fluency. If a victim is suffering from Wernicke’s aphasia, someone may speak sensibly to them, but to the victim the words make no sense. In both cases the wiring that processes speech, incoming or outgoing, is tangled and destroys the brain’s ability to parse language.
Precisely the same fate befalls ASL users who experience strokes that damage their speech centers, except in their case they lose their ability to sign, or comprehend signed language.28 ASL victims of Broca’s aphasia can sign, just as speaking victims can make wordlike sounds, but the signs, even though they resemble ASL, make no sense.29 Apparently these areas of the brain don’t see language in the form of sound alone, they process it as movement as well. Why? Arguably because those parts of the brain evolved the ability to understand gestures first, and spoken words later.
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There is no more dramatic example of how hand gestures and mimicry might have once evolved into true language than the remarkable story of students attending two schools created to help deaf and mute children in Nicaragua following the 1979 Sandinista revolution. If scientists could somehow drop out of nowhere and watch the evolution of a completely new language from scratch, this is as close as they could hope to come.
During the eight-year civil war that waged between the Nicaraguan government and Sandinista insurgents, a new government was formed in 1985. Early on it initiated a program to help the nation’s deaf, nonspeaking children. Two schools were opened in Managua, the country’s capital, and children poured in from around the country to attend them. Because of the long war, none of these children had been trained in any of the world’s two hundred known and accepted sign languages. At best they had only the rudimentary pantomimes each had developed out of necessity with their friends and families as they grew up—gestures for food or drink or sleep, but not much more.
Unfortunately, the teachers at the new schools weren’t much help to their language-impaired students. They had been urged by Soviet advisers to teach the children to finger-spell, a system that uses a single gesture for each letter in an existing language’s alphabet. The problem was, the children had absolutely no concept of an alphabet or words or any kind of language. They couldn’t spell with their hands any more than they could spell with their mouths. But the children did have an overwhelming desire to communicate. And so they did something extraordinary: They began to talk among themselves, using their hands. First they started with the basic mimes they had brought from their homes. With these as a foundation they next began to create an entirely unique language, all while their frustrated instructors stood by and watched in amazement.
In June 1986 the Nicaraguan Ministry of Education asked Judy Kegl, an ASL expert, to come to the schools to help the instructors understand what was going on. Kegl figured she would try to get an overview of the ways the children were communicating and thought she might then compile a rudimentary dictionary of the symbols the children were using. First she visited older, teenage students who were taking a hairdressing workshop. Though Kegl could sign ASL fluently, it did her no good because the only signing these students used was the variety they had fabricated on their own. In fact, she quickly realized that the gestures they used, while creative, were nothing like ASL. In fact, they were pretty awkward and didn’t seem to have anything like the underlying patterns you find in real speech, even gestured speech. It all seemed chaotic.
Many gestures—those for “eyebrow tweezers” or “rolling curler,” for example—were simply represented by miming the act, the way, perhaps, Homo erectus might have mimed “big predator” or “fluttering birds.” Some gestures were more complicated. One of the teenage girls showed Kegl a sign in which she laid her left palm flat, then with her right hand drew a squiggly line from the middle finger to the base of the palm. Then she turned her right hand over and pointed below the belt. Kegl didn’t get it right away, but eventually figured out she had just seen the sign for tampon.30
What Kegl was witnessing was a kind of gestural pidgin or protolanguage based on the hand movements the children had brought with them from home. These were the nonverbal versions of Bickerton’s Hawaiian-Japanese-English pidgin “aena tu macha churen, samawl churen, haus mani pei,” which explained why they had no real grammar or system of rules, at least not yet.
But just as Bickerton found that pidgins can transform themselves, sometimes within a single generation, into much more mature Creole languages complete with refined syntax and grammar, so did Kegl, except that she was shocked to find the salvation where she did.
After visiting the secondary school, Kegl made her way to San Judas, the primary school attended by the youngest deaf students. While there she noticed a girl named Mayela Rivas signing in the school’s courtyard with a rhythm and rapidity she hadn’t seen among the older children. She remembers thinking that the girl was using some sort of internal rule book as she signed. And in a sense she was.
The smaller children, it turned out, were pushing the old pidgin the older students had invented into new territory. Ann Senghas, who was a graduate student of Kegl’s in 1986, later said, “It was a linguist’s dream. It was like being present at the big bang.” In a paper she wrote for the journal Science, Senghas explained that the younger, not the older, children were taking concepts, things, or actions and breaking them down into discrete units—gestural symbols—and creating a true language.
The older children, on the other hand, tended to use gestures that painted a kind of moving picture of an action. Rolling downhill, for example, might be shown with a gesture that indicates both the type or manner of the movement (rolling) and the direction or path (down) at the same time with a flopping hand or jiggling line moving downward—something you or I might do in conversation to illustrate a point. But for complex communication this was too complicated and difficult for others to accurately repeat. It was like saying a long, jaw-breaking word that has a very narrow meaning. Such a word won’t very often be used because its meaning is so specific. It has no versatility.
The next generation of students didn’t simply learn to perform hand movements better than the older children, they redefined them by breaking them down into smaller signals that could be easily combined with others to express more ideas. Rather than indicating “rolling” and “down” in one elongated sign, they instead created one sign, or word, for “rolling” and a separate gesture for “down.” Rolling was indicated with a circular hand motion, quickly followed by “down,” which was indicated by placing the hand at the chest and then cutting the air and straightening the arm with a clear, downward motion, almost like a salute.
This is much more the way both true signed and verbal languages work, unlike nonverbal forms of communication
such as pictures or painting or mime. In speech, information comes in discrete bits like the sounds of letters and words that are then arranged in increasingly larger bits like phrases and sentences, all set in a certain order.
The other hallmark of language is that by breaking objects, actions, places, etc., into small pieces, communication becomes more flexible; each piece can be used and reused in different contexts to mean different things. This is how we transform a word such as “grip” from something that is a purely physical description, as in “I gripped the hammer,” to a highly emotional one: “Get a grip!” This is the very essence of metaphor and simile and context, which make all languages so elegant and powerful.
In the case of the Nicaraguan children, once they redefined the gesture for roll, they were now free to combine it with any number of other gestures to say “roll up” or “roll over,” or eventually, “I rolled the idea around in my head.” This makes the gestures less iconic and more symbolic, less mime-like and more versatile. The two innovations—discrete parts and reusable parts—characterize the flexibility that makes a language of finite words capable of expressing infinite numbers of ideas, describe an infinite number of scenes, or tell infinite varieties of stories. Like DNA or the keys played on a piano, they can be combined and recombined again and again with strikingly elegant and dramatic results. Just consider the millions of species and billions of unique human beings that the four-word vocabulary of DNA has created, or the number of musical notes that have been recombined into pieces as diverse as “Row, Row, Row Your Boat” and Rachmaninoff’s Prelude in C Minor.