Differences in Functional Connectivity between Patients with Depression with and without Nonsuicidal Self-injury
Hye-Jin Lee1, Young-Min Park1, Miseon Shim2
1Department of Psychiatry, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Korea
2Department of Artificial Intelligence, Tech University of Korea, Siheung, Korea
Correspondence to: Young-Min Park
Department of Psychiatry, Ilsan Paik Hospital, Inje University College of Medicine, 170 Juhwa-ro, Ilsanseo-gu, Goyang 10380, Korea
E-mail: medipark@hanmail.net
ORCID: https://orcid.org/0000-0002-4993-1426
Young-Min Park’s current affiliation is Psychiatric Clinic in Your Brain and Mind, Goyang, Korea.
Received: September 26, 2023; Revised: November 10, 2023; Accepted: November 14, 2023; Published online: December 6, 2023.
© The Korean College of Neuropsychopharmacology. All rights reserved.

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Objective: Nonsuicidal self-injury (NSSI), which involves deliberate harm to body tissues without suicidal intent, represents an escalating clinical concern. We used electroencephalography (EEG) to investigate the differences in functional connectivity (FC) patterns in patients with depression with and without a history of NSSI.
Methods: Seventy-seven patients with mood disorders experiencing major depressive episodes were categorized into NSSI (Group A; n = 31) and non-NSSI (Group B; n = 46) groups on the basis of their NSSI history. EEG data were collected and FC was analyzed using coherence (Coh), imaginary coherence (iCoh), and phase-locking value (PLV) metrics. Network indices based on graph theory were calculated. Demographic and clinical characteristics and scale scores were compared between groups A and B.
Results: While the two groups showed no significant differences in demographic characteristics such as age and diagnosis, the Beck Depression Inventory and Suicidal Ideation Questionnaire (SIQ) scores were higher in Group A. Binary logistic regression analyses revealed associations of NSSI with sex and the SIQ score. We examined the connectivity of 1,326 pairs of signals across six frequency bands, yielding 7,956 signal pairs. The two groups showed no significant differences in the Coh, iCoh, corrected PLV, or network indices but showed significant differences in all the frequency bands when an uncorrected t test was used.
Conclusion: In this study, FC differences in depression with and without NSSI were not observed. Further well-controlled research is expected to clarify neurobiological underpinnings and guide future interventions.
Keywords: Nonsuicidal self injury; Functional connectivity; Electroencephalography; Depression.

This Article