Altered pattern of brain dopamine synthesis in male adolescents with attention deficit hyperactivity disorder.
BACKGROUND
Limited data from positron emission tomography (PET) studies of subjects with attention-deficit/hyperactivity disorder (ADHD) indicate alterations in brain dopamine neurotransmission. However, these studies have used conventional univariate approaches that are less sensitive to detect complex interactions that may exist between different brain dopamine pathways and individual symptoms of ADHD. We aimed to investigate these potential interactions in adolescents with ADHD.


METHODS
We used a 3D PET scan to measure utilization of native L-[11C]-DOPA to map dopamine presynaptic function in various cortical, striatal and midbrain regions in a group of 8 male adolescents with ADHD and 6 age matched controls. To evaluate the interactions between the studied brain regions, multivariate statistical methods were used.


RESULTS
Abnormal dopaminergic function was found in multiple brain regions of patients with ADHD. A main finding was lower L-[11C]-DOPA utilization in adolescent with ADHD as compared to control subjects, especially in subcortical regions. This pattern of dopaminergic activity was correlated specifically with symptoms of inattention.


CONCLUSIONS
Dopamine signalling in the brain plays an important modulatory role in a variety of motor and cognitive functions. We have identified region-specific functional abnormalities in dopaminergic function, which may help better account for the symptoms of ADHD.
Forssberg
Hans
H
Neuropediatrics, Department of Women and Child Health, Karolinska Institutet, Stockholm, Sweden. hans.forssberg@ki.se
Fernell
Elisabeth
E
Waters
Susanna
S
Waters
Nicholas
N
Tedroff
Joakim
J