The Journal of the American Medical Association (JAMA.
2009;302(10):1084-1091) recently published work by Dr. Nora D.
Volkow, MD, et al regarding evaluation of the biological bases
that may reveal a reward/motivational deficit present in the
brains of persons with ADHD. Volkow and her colleagues theorized
that ADHD may be connected to reward-motivation deficits. Volkow
investigated whether lack of motivation and its relationship to
reward could be traced to depression of dopamine in various
areas of the brain. To determine whether dopamine was depressed
in ADHD persons, the researchers used positron emission
tomography (PET scans) to measure dopamine levels in 53
nonmedicated ADHD adults and 44 healthy non ADHD adults between
2001-2009. Since the biological mechanisms of ADHD are unknown,
studies of this type have become the holy grails of research.
While Volkow’s credentials are quite impressive (NIH, NIDA,
etc.) this research is not new or conclusive. The theory that
dopamine dysfunction/depression may be i