From ABC Science Online, News in Science, 17 August 2012:
Being able to lie about your age may soon be a thing of the past, after a new study shows the human brain develops at a consistent rate across individuals.
The finding could also advance our understanding of autism and ADHD, and be used in a court of law.
The team of US researchers used different magnetic resonance imaging (MRI) techniques to scan the brains of 885 people aged between 3 and 20 years. The images were used to identify more than two hundred structural brain features known to change over time in this age group.
“We have uncovered a ‘developmental clock’ of sorts within the brain -a biological signature of maturation that captures age differences quite well, regardless of other kinds of differences that exist across individuals,” says Dr Timothy Brown of the University of California, San Diego, lead author of the study, which appears in the journal Current Biology.
The researchers were able to assess an individual’s age with more than 92 per cent accuracy, beyond what’s been possible with any other biological measure.
“The fact that we found a collection of brain measures that so accurately captures a person’s chronological age means that brain development, or at least certain anatomical aspects of it, is more tightly controlled than we knew previously,” Brown says.
“The regularity in this maturity metric among typically developing children suggests that it might be sensitive to detecting abnormality as well.”