Changes in subcortical resting-state functional connectivity in patients with psychophysiological insomnia after cognitive–behavioral therapy

Study objectives: To examine the resting-state functional connectivity (FC) between subcortical regions in relation to whole-brain activity in patients with psychophysiological insomnia (PI) and changes following cognitive–behavioral therapy for insomnia (CBTi). Methods: The FC between subcortical seed regions (caudate, putamen, pallidum, amygdala, thalamus, and hippocampus) and whole-brain voxels were compared between the PI group (n=13, mean age: 51.0±10.2years) and good sleepers (GS, n=18, mean age: 42.7±12.3years). Also, in the PI group, FC was compared before and after 5weeks of CBTi. Results: Compared to the GS group, the PI group exhibited stronger FC between the thalamus and prefrontal cortex and between the pallidum and precuneus but weaker FC between the pallidum and angular gyrus, the caudate and orbitofrontal cortex, and the hippocampus and fusiform gyrus. After CBTi, the PI group exhibited decreased FC between the thalamus and parietal cortex, the putamen and motor cortices, and the amygdala and lingual gyrus, but increased FC between the caudate and supramarginal gyrus, the pallidum and orbitofrontal cortex, and the hippocampus and frontal/parietal gyri. Conclusions: The present findings demonstrate different FC in PI patients compared to GS and provide insight into the neurobiological rationale for CBTi. Keywords: Psychophysiological insomnia, Insomnia, Resting state, Functional magnetic resonance imaging, Cognitive–behavioral therapy, Functional connectivit