Researchers have designed a scanning test that can measure the maturity of the brain, a technology that may someday help doctors determine whether children are developing normally and identify those who might be at risk of certain mental disorders.
The brain scan uses functional connectivity magnetic resonance imaging, or fcMRI, which measures connections between regions of the brain. Unlike traditional fMRI scans, which simply show brain activity, fcMRI shows how various regions of the brain are talking with each other.
Led by Nico Dosenbach, a pediatric neurology resident at St. Louis Children’s Hospital, researchers performed fcMRI scans on 238 normally developing volunteers, ages 7 to 30. In five minutes, the scans measured more than 12,500 connections in the resting brain. Scientists used the 200 connections that were most reliably different between children and adults to generate a “brain maturation” curve.
Previous research has suggested that the typical child’s brain is characterized by localized, short-range connections; over time, these connections are pruned away and long-range connections increase. The authors of the new study, published in the current issue of Science, note that the loss of short-range connections seems to indicate brain maturity more than any other factor, and that the mature brain has fewer but sharper connections throughout.
Dosenbach and his colleagues suggest that the quick, five-minute fcMRI brain scan could eventually become standard practice, like measuring height and weight, to evaluate whether a child is maturing on schedule. It may also allow doctors to identify children at risk of autism, schizophrenia, ADHD or other problems associated with abnormal brain development. The same technology could then be used to measure how well a treatment is working.
But these goals are still a long way off, and the new findings still have to be borne out in further studies. Also, as the Washington Post points out, it’s not clear yet that such brain scans would add any truly useful information:
“Ultimately, the question for all these kinds of studies is: Does the brain imaging tell us more than we would learn by observing or asking or examining the participants?” said Anjan Chatterjee, a neuroscientist at the University of Pennsylvania. “Maybe this represents a step towards that possibility, but we are not there yet.”
Factors such as upbringing and other environmental influences remain important, several experts noted.
“There is a strange hold that neuroscience has on people, as if it is more real than what we know from observation,” Chatterjee said in an e-mail. “So, yes, parents might want such scans, but it is not clear that it would tell them something about their child’s maturity that they don’t already know — or a careful observer already knows.”