Baby Brainpower

What do babies know, and what are they capable of learning? These questions have always fascinated parents, and now there are some important new answers. Scientists are discovering that newborns€`once thought to enter the world as blank slates onto which a lifetime of experiences was inscribed€`have brains as sophisticated as the most powerful supercomputer, wired with a mind-boggling capacity for knowledge. Research has also shown that in the earliest months of life, a dazzling amount of brain development continues to occur. "What's novel in the 1990s is an intriguing set of theories that hadn't even been thought of as recently as fifteen years ago," says Sandra Ackerman, the author of Discovering the Brain (National Academy Press).

One of the areas scientists are exploring is infants' startling capacity for memory. But perhaps the most significant news concerns the impact of a baby's environment on the development of his brain.

Also, don't miss Mental Milestones at the end of this article for an age-by-age guide to the intellectual development of babies.

The Basics of Brainpower

It all starts with a series of bulges on a four-week-old embryo's neural tube. From there, billions of brain cells, called neurons, develop throughout the pregnancy. Connections between these cells, called synapses, also multiply rapidly during the nine months of gestation, forming the physical maps that allow learning to occur.

At birth, infants can feel, hear, and see (although vision is somewhat blurred). Within days they are able to recognize their mother's smell, and within weeks they can discriminate between her voice and the voices of others. Synapse formation continues at a rapid rate, allowing the baby to accomplish ever more complex tasks, such as forming her first sounds.

If you carefully observe your baby, you will probably notice that by about three or four months, she has a memory. If you show her a ball or toy, for example, then place it behind your back, you'll see that her eyes follow your action. She seems to remember the object and know where it is.

These kinds of observations by parents are borne out by research. "From following babies' eye movements we can observe that a three- or four-month-old does know that an object placed behind a screen or under a cloth is still there," confirms Adele Diamond, Ph.D., a developmental neuropsychologist and visiting faculty member at Massachusetts Institute of