Intrinsic Functional Connectivity in Attention-Deficit/Hyperactivity Disorder: A Science in Development

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Neuroimaging

Background:

• Resting-state functional magnetic resonance imaging (fMRI) research in Attention-Deficit/Hyperactivity Disorder (ADHD) is expanding rapidly.
• Early studies often overlooked the significant impact of head motion artifacts, a critical methodological concern.
• The ADHD-200 Consortium dataset has enabled more sophisticated analyses and replication efforts.

Purpose of the Study:

• To review current hypotheses regarding brain network alterations in ADHD using resting-state fMRI.
• To highlight methodological challenges, particularly head motion, and the need for analytical standardization.
• To emphasize the importance of mapping analytical space topography for future longitudinal studies.

Main Methods:

• Narrative review of existing literature on resting-state fMRI in ADHD.
• Discussion of hypotheses implicating default mode, cognitive control, and attention networks.
• Emphasis on the need for systematic evaluation of analytical parameter sensitivities.

Main Results:

• Current hypotheses implicate interactions between default, cognitive control, and attention networks in ADHD.
• Functional connectivity of reward and amygdala circuits may underlie dimensional aspects of ADHD.
• Methodological uncertainties, especially concerning head motion, require further investigation.

Conclusions:

• Standardizing analytical approaches and understanding their sensitivities are crucial for advancing ADHD neuroimaging research.
• Mapping the analytical space is essential before definitive testing of hypotheses and understanding developmental trajectories.
• Openly available datasets and prospective longitudinal studies are vital for future discoveries in neurodevelopmental disorders.