Poster 1

[P-1-04] Altered Resting-State Sensorimotor Network in Patients with Obsessive-Compulsive Disorder: an EEG Study

*Taegyeong Lee³, Sang-Shin Park², Chang-Hwan Im, Seung-Hwan Lee^1,2,3 (1.Inje University Ilsan Paik Hospital(Korea), 2.Bwave Inc.(Korea), 3.CEClab(Korea))

Keywords:

EEG,OCD,sensorimotor network,resting-state functional network,wPLI

Objective. Dysfunction in the cortical-striatal-thalamo-cortical (CSTC) circuits is a well-known pathological mechanism underlying obsessive-compulsive disorder (OCD). The imbalance between indirect pathway and direct pathway in CSTC circuits can contribute to the development of OCD, and these pathways are closely linked to the sensorimotor network [1]. Numerous neuroimaging studies have demonstrated alterations in the SMN of patients with OCD during the resting state. However, to the best of our knowledge, no study has confirmed SMN changes in patients with OCD using resting-state EEG (rsEEG), which has the advantage of capturing direct electrical activity and providing high temporal resolution. In this study, we compared the SMN between patients with OCD and healthy controls (HC) using rsEEG.Methods. Forty-one patients with OCD (aged 26.63 ± 10.63, W 15) and Forty-one HC (aged 29.32 ± 11.89, W 20) participated in this study. Eyes-closed rsEEG signals were acquired for 3 min. After signal pre-processing, rsEEG signals were divided into 2 s noise-free segments. To construct the SMN, eight regions of interest were employed as nodes, including the primary motor cortex (M1), supplementary motor area (SMA), primary sensory cortex (S1), and premotor cortex (PMC), each on both the right and left hemispheres. For edges, the weighted phase-lag index (wPLI) was applied as a measure of functional connectivity (FC) for 6 frequency bands: theta, low-alpha, high-alpha, low-beta, high-beta, and gamma bands. The global and local strengths of the SMN were calculated for the entire network and each ROI, respectively. The permutation test (n = 5,000) was utilized to compare the FC values and strength between the OCD group and the HC group for statistical analysis. The Bonferroni correction was conducted to account for multiple comparisons across frequency bands. Additionally, Pearson correlation test was conducted between y-bocs score and FC values or strength which showed significant differences.Results. In the theta band, FC between the LS1 and LSMA (p = 0.047, corrected) showed a significant difference, with the OCD group exhibiting higher FC values. In the high alpha band, FCs between LS1 and RM1 (p = 0.040, corrected) and between the LS1 and RPMC (p = 0.007, corrected) also exhibited significant differences, where the OCD group showed higher FC values. Global strength of SMN showed no significant difference between any frequency band. However, local strengths in the RPMC (p = 0.049, corrected) in the high alpha band was significantly higher in the OCD group than in the HC group.Conclusion. Our study suggests that abnormalities in the rsEEG-based SMN of patients with OCD have the potential to serve as biomarkers for the disorder. In particular, the hyper-connectivity between the LS1 and RM1 within the SMN in the high alpha band for patients with OCD may play a crucial role in serving as a biomarker.Reference.[1] Karas, P. J., Lee, S., Jimenez-Shahed, J., Goodman, W. K., Viswanathan, A., & Sheth, S. A. (2019). Deep brain stimulation for obsessive compulsive disorder: evolution of surgical stimulation target parallels changing model of dysfunctional brain circuits. Frontiers in neuroscience, 12, 998.