expressed in the brain. This promises a dramatic expansion in the ability to understand the interweaving of genetic and environmental influences as they affect both brain and behavioral development (see Nelson and Bloom, 1997).
Growth in brain knowledge naturally leads to questions about what it means for raising children and, specifically, for improving their development. Accordingly, efforts to translate this emerging knowledge for public consumption have proliferated in recent years. Some of this information has been portrayed well and accurately, but some has not. The challenge of deciphering what this information means for what parents, guardians, and teachers of young children should do is enormous. There are actually few neuroscience studies of very young children, and those that exist have not usually focused on the brain regions that affect cognition, emotions, and other complex developmental tasks.
Much of the fundamental knowledge about brain development is based on experimental studies of animals. The translation of this information from basic neuroscience into rules for application to humans can be quite straightforward when the mechanisms involved are very similar in humans and animals, as is the case with the developing visual system. But the interpretation of other data from animals, or even some data from humans (such as estimates of the density of synapses in various brain regions at various ages), can be extraordinarily complex or inappropriate when the brain mechanisms of cognition, language, and social-emotional development are addressed. In this context, it is essential to balance excitement about all the new learning with caution about the limits of what is understood today.
This chapter about the developing brain focuses on the role of experience in early brain development. Following a brief discussion of how to study the developing brain is an overview of early brain development from conception through the early childhood years. We then turn to a discussion of how early experiences contribute to brain development. Four themes run throughout this section:
Developmental neuroscience research says a great deal about the conditions that pose dangers to the developing brain and from which young children need to be protected. It says virtually nothing about what to do to create enhanced or accelerated brain development.
The developing brain is open to influential experiences across broad periods of development. This openness to experience is part of what accounts for the remarkable adaptability of the developing mind. Although there are a few aspects of brain growth that require particular kinds of experience at particular times, as far as we know at present, this is more the exception than the norm for human brain growth.