The Future of Children, Princeton - Brookings: Providing research and analysis to promote effective policies and programs for children.

How does the mind grow? Does it depend on crucial inputs from the environment? Or is it driven by its own innate information-processing abilities? What parent has not gazed at the casual play of a toddler and wondered if she or he is doing enough to stimulate intellectual growth? Developmental scientists respond to this parent's question in this way: the young mind is astonishingly active and self-organizing, creating new knowledge from everyday experiences. Sensitive parenting—not educational toys or Mozart CDs—provides the essential catalysts for early intellectual growth.⁴

From birth, a newborn's mind is active even though behavior is disorganized. Consider all of the intellectual equipment that enables newborns to begin engaging the world with their minds.⁵ From birth, newborns crave novelty and become bored with familiarity. Their eyes, ears, and other sensory organs are attuned to events that are new and from which they can learn. Their eyes are drawn to sharp contrasts and movement that help them discern the boundaries between objects and derive sophisticated inferences about object shape, size, rigidity, and wholeness. Newborns are capable of integrating knowledge gained from their different senses. They look toward the source of an interesting sound, or gaze at an object that matches the texture of the pacifier in their mouths.

These early capabilities provide the foundation for astonishing growth in concepts, causation, memory, and even problem solving in the early years. Consider concept development. The mind of an infant naturally clusters objects together that are similar in shape, texture, density, and other properties; and a toddler's mind categorizes faces, animals, and birds according to their properties (like nose size or leg length). On this basis, three- and four-year-olds make remarkably logical inferences about new members of a category—appreciating that a dolphin breathes like the mammal it is rather than the fish it resembles⁶—and enjoy displaying their new knowledge, as any parent of a dinosaur-loving preschooler knows. Consider, also, causation and problem solving. Infants are fascinated with "making things happen" through their actions. For example, they rapidly learn how to pull on a tablecloth to reach the milk. By preschool, young children become adept at manipulating physical objects and people to obtain their goals. Memory development also proceeds at a rapid pace. A baby's fragile memory for the past develops into a young child's flexible memory for routine events. And with an adult's help, preschoolers can remember unique and personally meaningful experiences, such as a trip to Disneyworld⁷, long afterward. Even numerical reasoning begins to emerge as an early awareness of the difference between small quantities grows into a young child's dawning ability to use number concepts (such as one-to-one correspondence) even before learning to count. Each of these accomplishments reveal an active mind that promotes its own growth by continuously revising its understanding based on how the world responds to its initiatives and observations.

A young infant's innate readiness to learn from experience is apparent in other ways as well. Newborns have a natural capacity for discriminating speech sounds that are used in all the world's languages, even those they have never heard and which their parents cannot discriminate. Newborns are, in a sense, "citizens of the world," innately prepared to learn any language. It is only later in the first year that their speech perception becomes specific to the sounds of the language they overhear at home. Newborns also prefer the appearance of human faces to other sights, and the sound of human voices to other sounds. Indeed, one experimental study⁸ showed that newborns prefer, above all, the sound of their mother's voice reading a story that she had repeatedly recited late in her pregnancy.

In early childhood, even more significant advances occur in language development. A three-year-old is already putting words together into simple sentences, mastering grammatical rules, and experiencing a "vocabulary explosion" that will result, by age six, in a lexicon of more than 10,000 words. New words are acquired at an amazing rate (five to six new words daily) as children employ intuitive rules for understanding the meanings of words on their first exposure to them.⁹ Young children thus quickly grasp the meanings of the words they overhear (even words they are not intended to hear). Language enables children to put their developing ideas and concepts into words they can share with others, and language revolutionizes thought by giving children access to the concepts, ideas, and values of other people. Although many important achievements in language development remain for the years that follow, early childhood establishes the basis for complex human reasoning and communication.

All of this learning occurs in a social context, of course. Even newborns respond in special ways to social stimuli, orienting to the people who provide their care and who offer the most interesting and stimulating experiences from which they can learn. Babies' interest in social sights, sounds, and speech focuses their active minds on interpreting and understanding human words, facial expressions, vocal intonations, and social behavior during even the most casually playful encounters.

The achievements of the mind draw upon, and contribute to, a young child's emotional and social development. A baby's delighted laughter, while kicking her legs to make the crib mobile shake, reveals the powerful emotional incentives that drive her to understand experience and master the world. Early word learning is built upon a toddler's interest in the intentions of an adult speaker. As young children begin to understand the hidden properties of animate and inanimate objects, they also discover the hidden psychological dimensions of other people, and begin to explore how beliefs, desires, and emotions influence the human actions they observe. This is why promoting school readiness is not simply a matter of encouraging literacy and number skills. It must also incorporate concern for enhancing the social and emotional qualities that underlie curiosity, self-confidence, eagerness to learn, cooperation, and self-control.

Young children thus do not learn about the world by themselves. A young mind's innate capabilities and its incessant activity each provide powerful avenues for understanding when aided by everyday experience and the behavior of other people. Safe, secure environments and playthings within easy reach permit a young child to explore things that can be examined, combined, and taken apart. Additional catalysts for intellectual growth arise from the natural, spontaneous behavior of sensitive adults. Caregivers do many things to stimulate mental growth. They create daily routines that enable young children to anticipate, represent, and remember routine daily events, such as preparing breakfast together, going to day care, or taking a bath before bed. Caregivers structure shared activities that are manageable for the children and that promote new skills and pride in achievement, such as working on a jigsaw puzzle or sharing a story.¹⁰ Caregivers promote language growth, from their sing-song "parentese" (which is optimally suited to enable babies to learn the sounds of the native language) to the continuing verbal patter they share with barely conversational young children (which enables children to begin to understand the significance of their everyday experiences). Parents and other caregivers do many things intentionally to promote learning and cognitive growth, but the most important intellectual catalysts they provide are uncoached and arise naturally from their unhurried, untroubled, sensitive encounters with the children they love.