Towards an understanding of unique and shared pathways in the psychopathophysiology of ADHD.
Most attention deficit hyperactivity disorder (ADHD) research has compared cases with unaffected controls. This has led to many associations, but uncertainties about their specificity to ADHD in contrast with other disorders. We present a selective review of research, comparing ADHD with other disorders in neuropsychological, neurobiological and genetic correlates. So far, a specific pathophysiological pathway has not been identified. ADHD is probably not specifically associated with executive function deficits. It is possible, but not yet established, that ADHD symptoms may be more specifically associated with motivational abnormalities, motor organization and time perception. Recent findings indicating common genetic liabilities of ADHD and other conditions raise questions about diagnostic boundaries. In future research, the delineation of the pathophysiological mechanisms of ADHD needs to match cognitive, imaging and genetic techniques to the challenge of defining more homogenous clinical groups; multi-site collaborative projects are needed.
Banaschewski
Tobias
T
Child and Adolescent Psychiatry, University of Göttingen, von-Siebold-Str. 5, D-37075 Göttingen, Germany. tbanasc@gwdg.de
Hollis
Chris
C
Oosterlaan
Jaap
J
Roeyers
Herbert
H
Rubia
Katya
K
Willcutt
Erik
E
Taylor
Eric
E
D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology* / Q000523:psychology*; D001321:Autistic Disorder / Q000503:physiopathology* / Q000523:psychology; D019955:Conduct Disorder / Q000503:physiopathology* / Q000523:psychology; D004410:Dyslexia / Q000503:physiopathology* / Q000523:psychology; D004525:Efferent Pathways / Q000473:pathology / Q000502:physiology; D006801:Humans; D009042:Motivation; D012559:Schizophrenia / Q000503:physiopathology*; D013998:Time Perception