Stanford study shows that tissue in the brain, rather than being lost, grows across childhood and may underlie better face recognition

People are born with brains riddled with excess neural connections. Those are slowly pruned back until early childhood when, scientists thought, the brain’s structure becomes relatively stable.

Now a pair of studies, published in the Jan. 6, 2017, issue of Scienceand Nov. 30, 2016, in Cerebral Cortex, suggest this process is more complicated than previously thought. For the first time, the group found microscopic tissue growth in the brain continues in regions that also show changes in function.

The work overturns a central thought in neuroscience, which is that the amount of brain tissue goes in one direction throughout our lives – from too much to just enough. The group made this finding by looking at the brains of an often-overlooked participant pool: children.

“I would say it’s only in the last 10 years that psychologists started looking at children’s brains,” said Kalanit Grill-Spector, a professor of psychology at Stanford and senior author of both papers. “The issue is, kids are not miniature adults and their brains show that. Our lab studies children because there’s still a lot of very basic knowledge to be learned about the developing brain in that age range.”