There is new research out of China using functional MRI testing (when the brain is at rest, rather than during a cognitive activity) that shows disrupted connections between different areas of the brain in children and adolescents with attention deficit hyperactivity disorder (ADHD).
ADHD is a “ neurobehavioral developmental condition that causes concentration problems, uncontrollable behavior and overactivity.”
The study was limited — done on males only and the group of subjects was small — but this is promising research which may lead to the ability to diagnose ADHD based on brain physiology.
Here is the link: http://www.medicalnewstoday.com/articles/276150.php