0301 ALTERED INTRINSIC FUNCTIONAL CONNECTIVITY OF FRONTOSTRIATAL REGIONS IN PATIENTS WITH PSYCHOPHYSIOLOGICAL INSOMNIA: A RESTING-STATE FMRI STUDY

Abstract Introduction: Insomnia has been characterized by state of hyperarousal. Patients with psychophysiological insomnia (PI) worry excessively about not being able to sleep. It disturbs relaxation and PI patients are less and less likely to fall asleep. In current study, we aimed to investigate intrinsic functional connectivity in patients with PI, especially in frontostriatal regions which is known as major nodes of circuit associated with arousal regulation. Methods: Thirteen patients with psychophysiological insomnia (51.0 ± 10.2y, 10 females) and 18 healthy good sleepers (42.7 ± 12.3y, 14 females) underwent resting-state functional MRI scan. We implemented seed-to-voxel functional connectivity analysis using the Harvard-Oxford Atlas as frontostriatal seed regions. Results: Compared with the good sleepers, PI patients showed increased frontal connectivity with the right lateral occipital, right occipital fusiform, right/left lingual gyrus and left amygdala. In addition, increased connectivity between right thalamus and right superior frontal, between right thalamus and right frontal pole, and between right pallidum and precuneus showed in PI patients. Decreased functional connectivity found between right caudate and right frontal pole, and between right pallidum and left lateral occipital in PI patients compared with the good sleepers. The strength of connectivity between the right pallidum and the precuneus in PI patients was positively correlated with the PSQI score (r = .67, p < .05). Conclusion: Current findings provide changes of intrinsic functional connectivity between various corticostriatal regions in patients with psychophysiological insomnia. Particularly, increased couplings with frontal cortex may support the hyperarousal theory in psychophysiological insomnia. Support (If Any): This research was supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (Study No.: 2013R1A1A2062517) and the Brain Research Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (Study No.: NRF-2016M3C7A1904336).