AUTHOR=Kim Ji Sun , Kang Eun-Sook , Bahk Yong Chun , Jang Sunglee , Hong Kyung Sue , Baek Ji Hyun 

TITLE=Exploratory Analysis of Behavioral Impulsivity, Pro-inflammatory Cytokines, and Resting-State Frontal EEG Activity Associated With Non-suicidal Self-Injury in Patients With Mood Disorder

JOURNAL=Frontiers in Psychiatry

VOLUME=Volume 11 - 2020

YEAR=2020

URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2020.00124

DOI=10.3389/fpsyt.2020.00124

ISSN=1664-0640

ABSTRACT=Introduction: Non-suicidal self-injury (NSSI) is a rapidly increasing mental health problem that requires more clinical attention. In this study, we aimed to explore the biobehavioral markers of NSSI in participants with mood disorders. 
Methods: A total of 45 participants with mood disorders (bipolar I, II, and major depressive disorder) were included in the study. Behavioral impulsivity was measured using the immediate memory task (IMT)/ delayed memory task (DMT) and the go-no-go (GNG) tests. Plasma levels of tumor necrosis factor- (TNF-), interleukin 1 beta (IL-1), and interleukin 6 (IL-6) and resting-state quantitative electroencephalography (qEEG) were measured. 
Results: The NSSI group had shorter GNG reaction time (GNG-RT) and higher TNF- levels compared to the non-NSSI group. TNF- was positively correlated with frontal theta power. In addition, GNG-RT showed a significant positive association with frontal alpha activity. 
Conclusion: NSSI in mood disorders was associated with increased behavioral impulsivity and greater inflammation. Increased pro-inflammatory cytokines were associated with frontal theta power and increased theta-beta ratio. Increased inflammation might change major neurotransmitter metabolism, which eventually affects frontal function and decreases response inhibition. Further studies to explore their causal relationship are warranted.