Alterations of cerebral perfusion and functional brain connectivity in medication-naive male adults with attention-deficit/hyperactivity disorder

Aims Functional brain abnormalities, including altered cerebral perfusion and functional connectivities, have been illustrated in adults with attention-deficit/hyperactivity disorder (aADHD). The present study attempted to explore the alterations of cerebral blood flow (CBF) and resting-state functional connectivity (RSFC) simultaneously to understand the neural mechanisms for adults with ADHD comprehensively. Methods Resting-state arterial spin labeling (ASL) and blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) data were acquired for 69 male aADHD and 69 matched healthy controls (HCs). The altered CBFs associated with aADHD were explored based on both categorical (aADHD vs HCs) and dimensional (correlation with aADHD core symptoms) perspectives. Then, the seed-based RSFC analyses were developed for the regions showing significant alterations of CBF. Results Significantly decreased CBF in the large-scale resting-state networks regions (eg, ventral attentional network, somatomotor network, limbic network) and subcortical regions was indicated in aADHD compared with HCs. The correlation analyses indicated that the hypoperfusion in left putamen/global pallidum and left amygdala/hippocampus was correlated with ADHD inattentive and total symptoms, respectively. Further, weaker negative functional connectivity between left amygdala and bilateral supplementary motor area, bilateral superior frontal gyrus, and left medial frontal gyrus was found in adults with ADHD. Conclusion The present findings suggested alterations of both cerebral perfusion and functional connectivity for the left amygdala in aADHD. The combination of CBF and RSFCs may help to interpret the neuropathogenesis of ADHD more comprehensively.