Jun Won Kim

Diagnostic utility of quantitative EEG in un-medicated schizophrenia

The aim of the current study was to evaluate the quantitative electroencephalography (QEEG) characteristics of patients with un-medicated schizophrenia (SPR) and to investigate the diagnostic utility of QEEG in assessing such patients during resting conditions. The subjects included 90 patients with schizophrenia and 90 normal controls. Spectral analysis was performed on the absolute power of all of the electrodes across five frequency bands following artifact removal. We conducted a repeated-measures ANOVA to examine group differences within the five frequency bands across several brain regions and receiver operator characteristic (ROC) analyses to examine the discrimination ability of each frequency band. Compared with controls, patients with schizophrenia showed increased delta and theta activity and decreased alpha 2 activity, particularly in the frontocentral area. There were no significant differences in the alpha 1 and beta activity. The ROC analysis performed on the delta frequency band generated the best result, with an overall classification accuracy of 62.2%. The results of this study confirmed the characteristics of the QEEG power in un-medicated schizophrenia patients compared with normal controls. These findings suggest that a resting EEG test can be a supportive tool for evaluating patients with schizophrenia.

Risk Factors for Smartphone Addiction in Korean Adolescents: Smartphone Use Patterns

With widespread use of the smartphone, clinical evidence for smartphone addiction remains unclear. Against this background, we analyzed the effect of smartphone use patterns on smartphone addiction in Korean adolescents. A total of 370 middle school students participated. The severity of smartphone addiction was measured through clinical interviews and the Korean Smartphone Addiction Proneness Scale. As a result, 50 (13.5%) were in the smartphone addiction group and 320 (86.5%) were in the healthy group. To investigate the effect of smartphone use patterns on smartphone addiction, we performed self-report questionnaires that assessed the following items: smartphone functions mostly used, purpose of use, problematic use, and parental attitude regarding smartphone use. For smartphone functions mostly used, the addiction group showed significantly higher scores in “Online chat.” For the purpose of use, the addiction group showed significantly higher “habitual use,” “pleasure,” “communication,” “games,” “stress relief,” “ubiquitous trait,” and “not to be left out.” For problematic use, the addiction group showed significantly higher scores on “preoccupation,” “tolerance,” “lack of control,” “withdrawal,” “mood modification,” “conflict,” “lies,” “excessive use,” and “loss of interest.” For parental attitude regarding childrens smartphone use, the addiction group showed significantly higher scores in “parental punishment.” Binary logistic regression analysis indicated that “female,” “use for learning,” “use for ubiquitous trait,” “preoccupation,” and “conflict” were significantly correlated with smartphone addiction. This study demonstrated that the risk factors for smartphone addiction were being female, preoccupation, conflict, and use for ubiquitous trait; the protective factor was use for learning. Future studies will be required to reveal the additional clinical evidence of the disease entity for smartphone addiction.

Relationship between theta-phase gamma-amplitude coupling and attention-deficit/hyperactivity behavior in children

The Continuous Performance Test (CPT) is a valuable tool for assessing behavior in attention-deficit/hyperactivity disorder (ADHD). Quantitative electroencephalography (QEEG) is a promising tool for the diagnosis of ADHD. Recently, theta-phase gamma-amplitude coupling (TGC) measurement has received attention because it is a feasible method of assessing brain function. We investigated the relationship between CPT performance and EEG measures such as TGC and theta and gamma activity. EEGs were recorded from 68 volunteers from a camp for hyperactive children using a 19-electrode system. Their TGC, theta and 40 Hz gamma activity were estimated and compared with results obtained on the Korean ADHD Rating Scale (KARS) and the Intermediate Visual and Auditory (IVA) CPT. The results demonstrated significant negative partial correlations between TGC and the IVA CPT, such as the Response Control Quotient (RCQ) and Attention Quotient (AQ). TGC successfully identified the level of dysfunctional interaction of the attention/arousal system at a multi-scale large network level. It is thought that as the TGC increases, the efficacy of the system is very low or dysfunctional. Compensatory hyper-arousal patterns of the dysfunctional attention/arousal system may account for this effect. TGC is a promising neurophysiological marker for ADHD behavior in children.

Factors associated with group bullying and psychopathology in elementary school students using child-welfare facilities

Purpose Low socioeconomic status is an important risk factor for child psychiatric problems. Low socioeconomic status is also associated with psychiatric problems later in life. We investigated the effects of group bullying on clinical characteristics and psychopathology in elementary school students using child-welfare facilities. Methods Three hundred and fifty-eight elementary school students using child-welfare facilities were recruited. The School Bullying Self Rating Questionnaire was used to assess group bullying. To evaluate related psychopathology, the Children’s Problem-Behavior Screening Questionnaire, the Children’s Depression Inventory, the Beck Anxiety Inventory, the Suicidal Ideation Questionnaire, Young’s Internet Addiction Scale, and Conners–Wells’ Adolescent Self-Report Scale were applied. Samples were classified according to school grade (lower or upper), and each group’s characteristics were compared as they related to bullying victims versus non-victims. Results The prevalence rate of group bullying was 22% in the lower-grade group and 12% in the higher-grade group. Bullying victims in lower grades reported high somatization, depressive symptoms, Internet addiction, and attention deficit hyperactivity disorder tendencies, whereas those in upper grades reported cognitive problems, symptoms of depression and anxiety, suicidal ideation, Internet addiction, and attention deficit hyperactivity disorder tendencies. Somatization and depressive symptoms were significant predictors of bullying in the lower-grade group, and anxiety was a significant predictor of bullying in the upper-grade group. Conclusion This study demonstrated that elementary school students using child-welfare facilities might have an increased risk of being bullied and that bullying victims may have different psychopathologies depending on their ages.

Desynchronization of Theta-Phase Gamma-Amplitude Coupling during a Mental Arithmetic Task in Children with Attention Deficit/Hyperactivity Disorder

Introduction Theta-phase gamma-amplitude coupling (TGC) measurement has recently received attention as a feasible method of assessing brain functions such as neuronal interactions. The purpose of this electroencephalographic (EEG) study is to understand the mechanisms underlying the deficits in attentional control in children with attention deficit/hyperactivity disorder (ADHD) by comparing the power spectra and TGC at rest and during a mental arithmetic task. Methods Nineteen-channel EEGs were recorded from 97 volunteers (including 53 subjects with ADHD) from a camp for hyperactive children under two conditions (rest and task performance). The EEG power spectra and the TGC data were analyzed. Correlation analyses between the Intermediate Visual and Auditory (IVA) continuous performance test (CPT) scores and EEG parameters were performed. Results No significant difference in the power spectra was detected between the groups at rest and during task performance. However, TGC was reduced during the arithmetic task in the ADHD group compared with the normal group (F = 16.70, p < 0.001). The TGC values positively correlated with the IVA CPT scores but negatively correlated with theta power. Conclusions Our findings suggest that desynchronization of TGC occurred during the arithmetic task in ADHD children. TGC in ADHD children is expected to serve as a promising neurophysiological marker of network deactivation during attention-demanding tasks.

Differences in Resting-state Quantitative Electroencephalography Patterns in Attention Deficit/Hyperactivity Disorder with or without Comorbid Symptoms

Objective The aim of the present study was to evaluate the role of comorbid psychiatric symptoms on quantitative electroencephalogram (QEEG) activities in boys with the attention deficit/hyperactivity disorder (ADHD). Methods All participants were male students in the second, third or fourth grade in elementary school. Therefore, there were no significant differences in age or sex. Participants with ADHD were assigned to one of three groups: pure ADHD (n=22), ADHD with depressive symptoms (n=11), or ADHD with problematic internet use (n=19). The Korean version of the Children’s Depression Inventory and the Korean Internet Addiction Self-scale were used to assess depressive symptoms and problematic internet use, respectively. Resting-state EEG during eyes closed was recorded, and the absolute power of five frequency bands was analyzed: delta (1–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), beta (12–30 Hz), and gamma (30–50 Hz). Results The ADHD with problematic internet use group showed decreased absolute theta power at the central and posterior region compared with the pure ADHD group. However, The ADHD with depressive symptoms group showed no significant differences compared with the other groups. Conclusion These findings will contribute to a better understanding of brain-based electrophysiological changes in children with ADHD in accordance with comorbid psychiatric symptoms.

Theta-phase gamma-amplitude coupling as a neurophysiological marker in neuroleptic-naïve schizophrenia

Theta-phase gamma-amplitude coupling (TGC) was used as an evidence-based tool to reflect the dysfunctional cortico-thalamic interaction in patients with schizophrenia. The aim of the present study was to evaluate the diagnostic utility of TGC. The subjects included 90 patients with schizophrenia and 90 healthy controls. We compared the TGC results between the groups using an analysis of covariance (ANCOVA) to adjust for age and sex and receiver operator characteristic (ROC) curve analyses to examine the discrimination ability of delta to gamma frequency bands and TGC. Patients with schizophrenia showed a significant increase in the resting-state TGC at all 19 electrodes. The analysis of the ROC curves for each frequency band exhibited relatively low classification accuracies for the delta, theta, slow alpha, fast alpha, and beta power. The TGC generated the most accurate results among the electroencephalography (EEG) measures, with an overall classification accuracy of 92.5%. The resting-state TGC value was increased in patients with schizophrenia compared to that in healthy controls and had a higher discriminating ability than the other parameters. These findings may be related to the compensatory hyper-arousal patterns of the dysfunctional default-mode network (DMN) in schizophrenia. Therefore, resting-state TGC is a promising neurophysiological marker of schizophrenia.

Psychopathological, temperamental, and characteristic factors in adults with remaining childhood attention-deficit hyperactivity symptoms

Abstract Objectives: To investigate differences in psychopathological, temperamental and characteristic factors between young adults with and without persistent Attention-Deficit Hyperactivity disorder (ADHD) symptoms. Methods: A total of 429 university students were divided into three groups: persistent adult ADHD (n = 53), only childhood ADHD (n = 56) and healthy controls (n = 320). The Korean Adult ADHD Scale, Korean Wender-Utah Rating Scale, Beck Depression Inventory-II, Beck Anxiety Inventory, Barratt Impulsiveness Scale, Korean Young Internet Addiction Scale, and Temperament Character Inventory-Revised (TCI-R; based on Cloninger’s seven factor model of temperament and character) were used to evaluate psychopathological factors. Results: Participants with persistent adult ADHD symptoms had significantly higher levels of childhood ADHD, depression, anxiety and the Internet addiction symptoms than did the only-childhood ADHD and control groups. The adult ADHD group also had significantly higher tendencies toward novelty seeking, harm avoidance, and self-transcendence, as well as low self-directedness and cooperativeness. Conclusions: Results suggest that persistent ADHD is associated with several unfavourable psychopathological, temperamental and characteristic factors. Therefore, thorough evaluation of these factors for childhood ADHD could help predict prognoses and provide treatment plans for preventing persistent ADHD into adulthood.

Age and sex-related differences in risk factors for elderly suicide: Differentiating between suicide ideation and attempts

The purpose of this study was to analyze the age and sex‐related differences in socio‐demographic factors that influence suicide ideation and attempts in the elderly.

Associations between urinary cotinine and symptoms of attention deficit/hyperactivity disorder and autism spectrum disorder

Background: The present study investigated associations between urinary cotinine levels as a biomarker of secondhand smoke exposure and symptoms of attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Methods: A total of 520 child participants (200 with ADHD, 67 with ASD, and 253 normal control subjects) were assessed using the Korean version of the ADHD rating scale (K‐ARS), Autism spectrum screening questionnaire (ASSQ), and Behavioral Assessment System for Children, second edition (BASC‐2). The Korean version of the computer‐based continuous performance test was used to assess cognitive function. Urinary cotinine was evaluated as a biomarker of secondhand smoke exposure. Results: Urinary cotinine levels were significantly and positively associated with K‐ARS score (B = 4.00, p < 0.001), ASSQ score (B = 1.71, p = 0.030), the behavioral problem subscales of the BASC‐2 (B = 1.68–3.52, p < 0.001–0.045), and omission and commission errors in the continuous performance test (B = 6.21–8.42, p < 0.001–0.019). Urinary cotinine levels were also associated with the increased odds ratio of ADHD (OR = 1.55, 95% CI 1.05–2.30, p = 0.028) and ASD (OR = 1.89, 95% CI 1.12–3.21, p = 0.018). Conclusion: Urinary cotinine levels were associated with lower behavioral adaptation and cognitive function and increased odds ratios of ADHD and ASD, indicating a negative effect of secondhand smoke exposure on the symptomatic manifestation of ADHD and ASD. HighlightsHigh urinary cotinine levels were positively associated with ADHD and ASD.Higher urinary cotinine levels were associated with externalizing behavioral problems.Exposure to secondhand smoke exacerbates ADHD and ASD symptoms.