Altered Function of Superior Parietal Lobule Associated with Perceptive Awareness in First-Episode Drug-Naïve Panic Disorders

Background: Biased perception plays an important role in the development and maintenance of panic disorder (PD), and high levels of cardiovascular symptoms in PD produce higher levels of heartbeat perception. Methods: Currently, we investigated brain activity during interoceptive awareness in PD using functional MRI. We recruited 18 subjects with first-episode drug--naive PD and 21 age- and gender-matched healthy controls (HCs). Results: We found that the heartbeat perception scores (HPSs) were higher in individuals with PD than in HCs. When comparing greater heartbeats or greater puretones with fixation, PD patients showed higher activity in the bilateral superior parietal lobule (SPL) than HCs. Further, patients with PD exhibited a significant positive correlation between BOLD activity in the left SPL and HPS during the heartbeats vs. fixation condition and a positive correlation between BOLD activity in the right SPL and HPS, although this did not reach significance. Interpretation: We identified impaired activation in the bilateral SPL during interoception and exteroception. The increased activation during interoceptive stimuli might render PD patients more engaged in processing information associated with their internal states, which may increase the probability of panic attacks. Our study provides insight regarding PD treatment, whereby inhibition of the SPL can be used to reduce cardiac interoceptive accuracy and relieve cardiac syndromes. Funding Statement: This work was supported by grants from the National Natural Science Foundation of China (81071098), Shanghai Science and Technology Committee (15411950201， 15ZR1435500, 18ZR1432600, 18411952400), Shanghai Jiao Tong University Foundation (YG2016MS37), and Shanghai Municipal Commission of Health and Family Planning Foundation (20164Y0215). Declaration of Interests: The Authors declare that there is no conflict of interest. Ethics Approval Statement: This study was approved by the Research Ethics Committee at the SMHC, where the participants were recruited and assessed. All participants provided informed consent, and the consent was written in the study