Watch him roll! Baby Edward's amazing brain

January 6, 2011

Robert Krulwich

He rocks. He rolls. He sucks. He kicks. He tongues. He handles. He flips. He touches. There's not a single item in this living room that 9 month old Charles-Edward (aka Edward) doesn't explore (for a while I thought he'd ignore the chair in the upper left corner, but no...).

Edward (son of Quebec City journalist/photographer Francis Vachon) is a rolling demonstration of what the neuroscientists call "synaptic exuberance." You can't see what's happening in his brain, but he is forming ten, twenty thousand new connections every second. Watch him go.

Here's the thing about babies. When we're born, we get the brain cells we need, but the connections between cells haven't formed yet. In those first few years as we explore the world, the cells begin to link up at a dizzying pace, forming tens of thousands, even millions of new links. When you watch Edward you can almost feel it happening.

Look inside a baby brain and you can see the brain cells getting bushier with more and more links to other cells. But the strange thing is, we babies overdo it.

Look at this progression:

All of us, not just Edward, form more connections than we need. Then, later on, (different regions of the brain do this at different times, but it goes on into our teen years) there's a strange reversal. Millions of connections start to die. Why does this happen? Why do babies have a sudden burst of synaptic exuberance around Edward's age and then start losing the connections?

This is still something of a mystery says Dr. Harry Chugani at Wayne State University in Detroit.

Why does a child's brain demand twice the energy of an adult's brain? Why do some areas in the brain mature before others? And what about one of the most fascinating aspects of brain development -- the discovery that the brain produces "too much" of various neural elements and then eliminates the excess? In some ways, this is analogous to the sculptor who begins with more material than is required and then subtracts the excess material to obtain a desired form. Unlike the sculptor, however, who eventually achieves a final form, the brain is able to undergo some remodeling throughout life.

...This way, brain circuits are created and strengthened, in part, by whatever environment and experiences the baby encounters.

This allows for a fine-tuning of neuronal circuits, based on early exposure and environmental nurturing, that makes the neuronal architecture of each person unique.

What he's saying is babies go wild making connections and then, as we grow into our preferences, our personalities, life is like a scalpel. We slowly shed what we don't need or use or want.  Having watched Edward for those time lapsed four hours, it's hard to imagine what he’s going to give up later in life but he's got to give up something. We all do.


Charles-Edward was accompanied in the video by "Ensemble," performed by Coeur de Pirate, and don't worry, he wasn't left alone for four hours. Adult interventions were edited out. If you want to see Francis and his son, they can be found here.

Harry Chugani is Chief of the division of Pediatric Neurology at Children's Hospital of Michigan and professor of pediatrics, neurology, and radiology at Wayne State University in Detroit. Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.