Functional neuroanatomy of working memory in adults with attention-deficit/hyperactivity disorder.
BACKGROUND
Attention-deficit/hyperactivity disorder (ADHD) in adults is an increasingly recognized psychiatric disorder, linked with impairments in numerous life domains and with neurocognitive dysfunctions. However, the neural substrate of cognitive functioning in adults with this disorder has been relatively unexamined. The objective of this study was to examine neural functioning in ADHD adults during performance on a verbal working memory task.


METHODS
A sample of unmedicated adults with ADHD (n = 20) and control subjects (n = 20) performed a 2-back task of working memory, and the blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) response was used as a measure of neural activity during working memory performance.


RESULTS
Though working memory performance did not differ significantly between ADHD adults and control subjects, ADHD adults showed significantly decreased activity in cerebellar and occipital regions and a trend toward decreased activation in an a priori predicted region of the prefrontal cortex.


CONCLUSIONS
ADHD adults showed altered patterns of neural activity despite comparable performance on a verbal working memory task. These findings suggest that the cerebellum is involved in the pathophysiology of at least some cognitive deficits associated with ADHD and emphasize the need for additional research aimed at elucidating the role of the cerebellum in ADHD symptomatology.
Valera
Eve M
EM
Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02129, USA. eve_valera@hms.harvard.edu
Faraone
Stephen V
SV
Biederman
Joseph
J
Poldrack
Russell A
RA
Seidman
Larry J
LJ
D000293:Adolescent; D000328:Adult; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000503:physiopathology*; D001931:Brain Mapping; D002531:Cerebellum / Q000098:blood supply / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000098:blood supply / Q000503:physiopathology*; D011930:Reaction Time / Q000502:physiology
D010100:Oxygen