Jeong-Cheol Seo, Duk-In Jon, Se-Hoon Shim, Hyung-Mo Sung, Young Sup Woo, Jeongwan Hong, Sung‐Yong Park, Jeong Seok Seo, Won-Myong Bahk. Clin Psychopharmacol Neurosci 2022;20:126-34. https://doi.org/10.9758/cpn.2022.20.1.126

Jeongjae Bak, Se-Hoon Shim, Young-Joon Kwon, Hwa-Young Lee, Ji Sun Kim, Heejung Yoon, and Yeon Jung Lee. Clin Psychopharmacol Neurosci 2018;16:95-102. https://doi.org/10.9758/cpn.2018.16.1.95

Relatively little is investigated regarding the neurophysiology of adult attention-deficit/hyperactivity disorder (ADHD). Mismatch negativity (MMN) is an event-related potential component representing pre-attentive auditory processing, which is closely associated with cognitive status. We investigated MMN features as biomarkers to classify drug-naive adult patients with ADHD and healthy controls (HCs). Sensor-level features (amplitude and latency) and source-level features (source activation) of MMN were investigated and compared between the electroencephalograms of 34 patients with ADHD and 45 HCs using a passive auditory oddball paradigm. Correlations between MMN features and ADHD symptoms were analyzed. Finally, we applied machine learning to differentiate the two groups using sensor- and source-level features of MMN. Adult patients with ADHD showed significantly lower MMN amplitudes at the frontocentral electrodes and reduced MMN source activation in the frontal, temporal, and limbic lobes, which were closely associated with MMN generators and ADHD pathophysiology. Source activities were significantly correlated with ADHD symptoms. The best classification performance for adult ADHD patients and HCs showed an 81.01% accuracy, 82.35% sensitivity, and 80.00% specificity based on MMN source activity features. Our results suggest that abnormal MMN reflects the adult ADHD patients’ pathophysiological characteristics and might serve clinically as a neuromarker of adult ADHD.

Ji Sun Kim, Young Joon Kwon, Hwa Young Lee, Ho-Sung Lee, Sungkean Kim, Se-hoon Shim. Clin Psychopharmacol Neurosci 2020;18:127-35. https://doi.org/10.9758/cpn.2020.18.1.127

Objective The objective of the present study was to explore causal pathways to understand how second traumatic experiences could affect the development of emotional exhaustion and psychiatric problems.Methods A total of 582 workers who had jobs vulnerable to secondary traumatic experiences were enrolled for this study. Emotional exhaustion, secondary trauma, resilience, perceived stress, depression, anxiety, and sleep problems were evaluated. A model with pathways from secondary traumatic experience score to depression and anxiety was proposed. The participants were divided into three groups according to the resilience: the low, middle and high resilience group.Results Resilience was a meaningful moderator between secondary traumatic experiences and psychiatric problems. In the path model, the secondary trauma and perceived stress directly and indirectly predicted perceived stress, emotional exhaustion, depression, anxiety, and sleep problems in all three groups. Direct effects of perceived stress on depression and anxiety were the largest in the low resilience group. However, direct effects of secondary trauma on perceived stress and emotional exhaustion were the largest in the high resilience group.Conclusion Understanding the needs of focusing for distinct psychological factors offers a valuable direction for the development of intervention programs to prevent emotional exhaustion among workers with secondary traumatic experiences.