"This study localized exactly where this volume change takes place," she said. "And it points to the prefrontal cortex, which is involved with organizing, planning, timing and sequencing of events." Elia added that these are all functions that kids with ADHD find difficult to perform.
The idea of brain imaging to detect ADHD early may seem tempting, but most doctors agree that it is not ready for use as a diagnostic tool.
"Although the delay in cortex development was marked, it could only be detected when a very large number of children with the disorder were included," Shaw noted in an NIMH press release. "It is not yet possible to detect such delay from the brain scans of just one individual. The diagnosis of ADHD remains clinical, based on taking a history from the child, the family and teachers."
"But it does lay the groundwork for using brain imaging clinically in the future," said Elia.
There is a slight word of caution, though, amid the general excitement. According to Larry Seidman, professor of psychology at Harvard Medical School, "The use of the word 'delay' could be misinterpreted to mean that children with ADHD will 'catch up.'
"As of now, we don't have evidence that they catch up in their brain development."