ADHD- and medication-related brain activation effects in concordantly affected parent-child dyads with ADHD.
BACKGROUND
Several studies have documented fronto-striatal dysfunction in children and adolescents with attention deficit/hyperactivity disorder (ADHD) using response inhibition tasks. Our objective was to examine functional brain abnormalities among youths and adults with ADHD and to examine the relations between these neurobiological abnormalities and response to stimulant medication.


METHODS
A group of concordantly diagnosed ADHD parent-child dyads was compared to a matched sample of normal parent-child dyads. In addition, ADHD dyads were administered double-blind methylphenidate and placebo in a counterbalanced fashion over two consecutive days of testing. Frontostriatal function was measured using functional magnetic resonance imaging (fMRI) during performance of a go/no-go task.


RESULTS
Youths and adults with ADHD showed attenuated activity in fronto-striatal regions. In addition, adults with ADHD appeared to activate non-fronto-striatal regions more than normals. A stimulant medication trial showed that among youths, stimulant medication increased activation in fronto-striatal and cerebellar regions. In adults with ADHD, increases in activation were observed in the striatum and cerebellum, but not in prefrontal regions.


CONCLUSIONS
This study extends findings of fronto-striatal dysfunction to adults with ADHD and highlights the importance of frontostriatal and frontocerebellar circuitry in this disorder, providing evidence of an endophenotype for examining the genetics of ADHD.
Epstein
Jeffery N
JN
Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA. jeff.epstein@cchmc.org
Casey
B J
BJ
Tonev
Simon T
ST
Davidson
Matthew C
MC
Reiss
Allan L
AL
Garrett
Amy
A
Hinshaw
Stephen P
SP
Greenhill
Laurence L
LL
Glover
Gary
G
Shafritz
Keith M
KM
Vitolo
Alan
A
Kotler
Lisa A
LA
Jarrett
Matthew A
MA
Spicer
Julie
J
D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000503:physiopathology*; D001921:Brain / Q000187:drug effects* / Q000503:physiopathology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology* / Q000627:therapeutic use; D002648:Child; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008774:Methylphenidate / Q000494:pharmacology* / Q000627:therapeutic use; D010287:Parent-Child Relations
D000697:Central Nervous System Stimulants; D008774:Methylphenidate