Objective: To study the differences of brain functions between children with attention deficit hyperactivity disorder (ADHD) predominantly inattentive (ADHD-I) and combined (ADHD-C) subtypes in resting state using functional magnetic resonance imaging (fMRI).
Methods: A newly reported regional homogeneity (ReHo) approach was used to analyze blood oxygen level-dependent fMRI (BOLD-fMRI) data in resting state among 6 ADHDj C, 9 ADHD-I and 15 normal control boys.
Results: The brain regions showing differences among the three groups included bilateral frontal lobe, right cuneus and right inferior temporal gyrus. Compared with the normal controls, ADHD-C showed decreased ReHo in left frontal lobe and right inferior temporal gyrus, ADHD-I showed decreased ReHo in bilateral frontal and temporal lobe and right cerebellum and increased ReHo in bilateral occipital lobe and right inferior parietal gyrus. There were no brain regions showing different ReHo between ADHD-C and ADHD-I.
Conclusion: Although both ADHD-C and ADHD-I showed abnormal neural activity in resting state compared with the normal controls, there were no differences for brain functions in resting state between ADHD-C and ADHD-I.