Quasi-periodic patterns of brain activity in individuals with Attention-Deficit/Hyperactivity Disorder

Individuals with attention-deficit/hyperactivity disorder have been shown to have disrupted functional connectivity in the default mode and task positive networks. Traditional fMRI analysis techniques that focus on static changes in functional connectivity have been successful in identifying differences between healthy controls and individuals with ADHD. However, such analyses are unable to explain the mechanisms behind the functional connectivity differences observed. Here, we study dynamic changes in functional connectivity in individuals with ADHD through investigation of quasi-periodic patterns (QPPs). QPPs are reliably recurring low-frequency spatiotemporal patterns in the brain linked to infra-slow electrical activity. They have been shown to contribute to functional connectivity observed through static analysis techniques. We find that QPPs contribute to functional connectivity specifically in regions that are disrupted during ADHD. Individuals with ADHD also show differences in the spatiotemporal pattern observed within the QPPs. This difference results in a weaker contribution of QPPs to functional connectivity in the default mode and task positive networks. We conclude that quasi-periodic patterns provide insight into the mechanisms behind functional connectivity differences seen in individuals with ADHD. This allows for a better understanding of the etiology of the disorder and development of effective treatments.\n\nHighlights O_LIDefault mode and task positive network connectivity is disrupted in ADHD\nC_LIO_LIQuasi-periodic patterns contribute to typical functional connectivity in the DMN and TPN\nC_LIO_LIThe contribution of QPPs to functional connectivity is diminished in individuals with ADHD\nC_LIO_LIQPPs could explain BOLD dynamics underlying static functional connectivity differences in ADHD\nC_LI