Babies Found to Assemble Building Blocks--of Speech

Babies struggling to turn babble into polished patter use a previously undiscovered instinct for rules to master the building blocks of language, scientists at New York University announced Thursday.

The new insight is persuasive evidence that the ability to think in terms of formulas and rules is not just something that must be learned through schooling, as some scholars have argued, but is also a fundamental characteristic of every human mind, several language experts said.

“Babies are built to learn rules . . . with lightning speed,” said psychologist Paul Bloom, an expert on language development at the University of Arizona.

Working with 7-month-old infants, the NYU researchers determined that even the very young can make sense of speech by figuring out on their own simple rules about the patterns of language structure and grammar. Moreover, the babies appear to deduce these formal rules well before they can understand what words mean or how to say them, at an age when the infant brain--with twice as many neurons and twice as energetic as an adult brain--is almost exploding with vitality.

“This is a universal property of the human mind,” said NYU psychologist Gary Marcus, who led the research team. “Abstract rules form the core of everything from computer programs to grammars. Our results show that babies’ minds are built to look for such rules--even without being told.”

The research, published today in Science, broadens the understanding of what may be built into every human brain at birth, from a rudimentary knowledge of shapes and numbers to a surprisingly well-stocked intellectual tool kit for learning what may be the most complex means of communication yet devised--human speech.

The work is certain to renew a fierce debate among linguists, psychologists and cognitive scientists over the nature of language and its place in the architecture of the human mind.

From earliest infancy, the new research suggests, the human mind is designed to handle symbols and variables--whether they are abstract numbers or words--in a manner reminiscent of a computer program.

“I think it is a very significant discovery,” said cognitive scientist Steven Pinker at the Massachusetts Institute of Technology.

“This sensitivity to abstract patterns might indeed be one of the distinctive traits of the human mind,’ Pinker said. “It could be that this kind of information processing is one of the major things our bigger brain evolved to do.”

Whether fundamental knowledge of language is somehow hard-wired by evolution into the human brain--in the form of a universal grammar that underlies every language--or acquired from scratch by every newborn from its parents and the culture it inhabits is the stuff of scholarly brawls.

Hard evidence of how language arises in the mind often is indirect at best.

To study how infants responded to language structure, Marcus and his colleagues conducted three experiments with 16 infants using an artificial language devised for the tests.

Each infant listened for two minutes to a series of three-word sentences that conformed to a uniform pattern. Then the infants listened to a series of different sentences, some of which followed the original structure, and some of which were scrambled.

In their report, the researchers found that 90% of the infants were able to recognize the sentence structure they had heard before, based simply on their ability to quickly master the patterns of sentence components--the essence of grammar.

The researchers took care to ensure that the children were not simply responding to familiar sounds or to pleasant sequences of syllables.

“Of course, babies of this age don’t literally know nouns, verbs, and adjectives,” Marcus said. “But our results show that they understand the algebra of how to put words together into sentences.”

Exploring the anatomy of language, experts have discovered that nature has forged remarkably intimate connections between parent and child that act to shape the structures of the developing brain. The new finding is the latest in a series of recent discoveries rooted in the biology of words.

No matter what language is spoken, for example, adults around the world croon to infants in a universal baby-talk. The melodious singsong of this “parentese,”, with distorted tones, variable pitch and drawn-out vowels, teaches the phonetic building blocks of each baby’s mother tongue, researchers at the University of Washington in Seattle recently determined.

Under the unconscious influence of such baby-talk, infants at 20 weeks of age already are attuned to the nuances of vowel sounds and, by the age of 6 months, are responding to sounds differently depending on their native language.

At the same time, the infant brain is so receptive to people around it that children as young as 6 months can learn new behaviors simply by observing the actions of other people for as little as 30 seconds, child psychologists at the University of Otago in New Zealand reported. And researchers at the University of Wisconsin in Madison recently discovered that infants can recognize how words begin and end by detecting statistical patterns in speech.

That alone, some researchers believe, is more than enough to account for an infant’s ability to master language.

“Babies are big, mean learning machines,” said Elizabeth Bates, director of the UC San Diego Center for Research in Language. “The big mistake of the past 30 years is to underestimate the extraordinary power of learning and the plasticity of the human brain, especially in the early years.”

Although Bates and others do not think babies necessarily require any special affinity for rules in order to learn language, UCLA linguist Victoria Fromkin said the ability to sense patterns and rules in speech is a critical learning mechanism that every newborn needs to pick up the formal nuances of language.

“That is a really very important finding,” Fromkin said. “The question of how children acquire language without being taught is a major issue.”