Visual cortex abnormalities in adults with ADHD: a structural MRI study.
OBJECTIVE
Most structural imaging studies in ADHD have focused on prefronto-striatal circuits. However, findings remained inconsistent while recent reports point to the posterior parietal cortex as an additional target for research. Moreover, although adult ADHD clinically differs from the childhood presentation little is known about the structural correlates of ADHD in adults. The aim of this study was to clarify the involvement of prefronto-striatal and posterior parietal areas in adult ADHD.


METHODS
Voxel-based morphometry of high resolution MRI scans was applied to analyze volumetric brain differences between 31 adult patients with ADHD and 31 control subjects.


RESULTS
The volume of prefrontal, striatal and parietal gray matter was normal. ADHD patients displayed a significant reduction of gray matter volume bilaterally in the early visual cortex (P<0.04).


CONCLUSIONS
The unexpected finding of visual cortex abnormalities might be related to impairments in early-stage, 'subexecutive" attentional mechanisms. The results support the notion that executive dysfunction may not be the dominant neurobiological characteristic of ADHD at least in adult patients. The visual cortex deserves more consideration as a potentially important site of dysfunction in adult and possibly childhood ADHD.
Ahrendts
Johannes
J
Section for Experimental Neuropsychiatry, Department of Psychiatry and Psychotherapy, University of Freiburg Medical Center, Freiburg, Germany.
Rüsch
Nicolas
N
Wilke
Marko
M
Philipsen
Alexandra
A
Eickhoff
Simon B
SB
Glauche
Volkmar
V
Perlov
Evgeniy
E
Ebert
Dieter
D
Hennig
Jürgen
J
van Elst
Ludger Tebartz
LT
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D016477:Artifacts; D001289:Attention Deficit Disorder with Hyperactivity / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014793:Visual Cortex / Q000002:abnormalities* / Q000473:pathology*; D055815:Young Adult