Atypical default network connectivity in youth with attention-deficit/hyperactivity disorder.
BACKGROUND
Attention-deficit/hyperactivity disorder (ADHD) is a major public health concern. It has been suggested that the brain's default network may provide a crucial avenue for understanding the neurobiology of attention deficit/hyperactivity disorder. Evaluations of the default network have increased over recent years with the applied technique of resting-state functional connectivity magnetic resonance imaging (rs-fcMRI). These investigations have established that spontaneous activity in this network is highly correlated at rest in young adult populations. This coherence seems to be reduced in adults with ADHD. This is an intriguing finding, as coherence in spontaneous activity within the default network strengthens with age. Thus, the pathophysiology of ADHD might include delayed or disrupted maturation of the default network. If so, it is important to determine whether an altered developmental picture can be detected using rs-fcMRI in children with ADHD.


METHODS
This study used the typical developmental context provided previously by Fair et al. (2008) to examine coherence of brain activity within the default network using rs-fcMRI in children with (n = 23) and without attention deficit/hyperactivity disorder (n = 23).


RESULTS
We found that functional connections previously shown as developmentally dynamic in the default network were atypical in children with attention deficit/hyperactivity disorder-consistent with perturbation or failure of the maturational processes.


CONCLUSIONS
These findings are consistent with the hypothesis that atypical consolidation of this network over development plays a role in attention deficit/hyperactivity disorder.
Fair
Damien A
DA
Department of Psychiatry, Oregon Health and Science University, Portland, 97239, USA. damien.fair@aya.yale.edu
Posner
Jonathan
J
Nagel
Bonnie J
BJ
Bathula
Deepti
D
Dias
Taciana G Costa
TG
Mills
Kathryn L
KL
Blythe
Michael S
MS
Giwa
Aishat
A
Schmitt
Colleen F
CF
Nigg
Joel T
JT
D000293:Adolescent; D000367:Age Factors; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D001921:Brain / Q000254:growth & development / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology*