Gi Jung Hyun
Chung-Ang University
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Computers in Human Behavior | 2015
Gi Jung Hyun; Doug Hyun Han; Young Sik Lee; Kyoung Doo Kang; Seo Koo Yoo; Un Sun Chung; Perry F. Renshaw
Psychopathological conditions are the strongest predicting factors for online game addiction.Sex is a risk factor for online game addiction.Decreased self-esteem is associated with online game addiction. Online gaming addiction has been increasingly recognized as a mental disorder. However, the predictive factors that lead to online gaming addiction are not well established. The aim of this study was to identify factors that may influence the development of online gaming addiction. A total of 263 patients with problematic online gaming addiction (255 males (97%) and 8 females (3%), age: mean=20.4?5.8years) and153 healthy comparison subjects (118 males (77%) and 35 females (23%), age: 21.2?5.5years, range) were recruited for participation in the current study. Hierarchical logistic regression analyses among each set of variables were conducted. Individual factors (sex and age), cognitive factors (IQ and perseverative errors), psychopathological conditions (ADHD, depression, anxiety, and impulsivity), and social interaction factors (family environment, social anxiety, and self-esteem) were evaluated in a stepwise fashion. All four factors were associated with online gaming addiction, with psychopathological conditions being the strongest risk factors for the addiction. Individual factors, psychological factors, and social interactions were associated with the development of pure online gaming addiction. As before, psychological factors (attention, mood, anxiety and impulsivity) were the strongest risk factors for online gaming addiction in patients with pure online gaming addiction. Psychopathologies, including ADHD and depression, were the strongest factors associated with the development of online gaming addiction in individuals.
Psychiatry Investigation | 2013
Gi Jung Hyun; Yong Wook Shin; Bung Nyun Kim; Jae Hoon Cheong; Seong Nam Jin; Doug Hyun Han
Objective The bulk of recent studies have tested whether video games change the brain in terms of activity and cortical volume. However, such studies are limited by several factors including cross-sectional comparisons, co-morbidity, and short-term follow-up periods. In the present study, we hypothesized that cognitive flexibility and the volume of brain cortex would be correlated with the career length of on-line pro-gamers. Methods High-resolution magnetic resonance scans were acquired in twenty-three pro-gamers recruited from StarCraft pro-game teams. We measured cortical thickness in each individual using FreeSurfer and the cortical thickness was correlated with the career length and the performance of the pro-gamers. Results Career length was positively correlated with cortical thickness in three brain regions: right superior frontal gyrus, right superior parietal gyrus, and right precentral gyrus. Additionally, increased cortical thickness in the prefrontal cortex was correlated with winning rates of the pro-game league. Increased cortical thickness in the prefrontal and parietal cortices was also associated with higher performance of Wisconsin Card Sorting Test. Conclusion Our results suggest that in individuals without pathologic conditions, regular, long-term playing of on-line games is associated with volume changes in the prefrontal and parietal cortices, which are associated with cognitive flexibility.
Psychiatry Investigation | 2017
Sun Mi Kim; Gi Jung Hyun; Tae-Woon Jung; In-Hee Cho; Baik Seok Kee; Doug Hyun Han
Objective We aimed to assess disturbances in postural and gait balance and functional connectivity within the brain regions controlling balance in children with attention-deficit/hyperactivity disorder (ADHD). Methods Thirteen children with ADHD and 13 age- and sex-matched controls were recruited. Gait balance was assessed by the difference in the center of pressure (COP) between the left and right foot, as well as the difference in plantar pressure between the left and right foot during gait. Neuroimaging data were acquired using a 3.0 Tesla MRI scanner. Functional connectivity between the vermis of the cerebellum and all other brain regionswas assessed. Results The difference in plantar pressure between the left foot and right foot in the ADHD group was greater than that observed in the control group. The average COP jerk score of the right foot in the ADHD group was higher than that observed in the control group. A higher functional connectivity between the cerebellum and the right middle frontal gyrus (premotor cortex) and medial frontal gyrus (cingulate gyrus) was observed in the control group relative to the ADHD group. In the ADHD group, the difference in plantar pressure between the left and right foot was also negatively correlated with the beta-value within the middle frontal gyrus. Conclusion Children with ADHD had disturbance of balance as assessed by plantar pressure. Decreased brain connectivity from the cerebellum to the premotor cortex and anterior cingulate was associated with disturbances of posture and balance in children with ADHD.
Computer Methods and Programs in Biomedicine | 2018
Gi Jung Hyun; Jin Wan Park; Jin Hee Kim; Kyoung Joon Min; Young Sik Lee; Sun Mi Kim; Doug Hyun Han
BACKGROUND AND OBJECTIVE Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder hypothesized to involve impaired visuospatial working memory (VSWM). However, there are few studies utilizing neuropsychological tests to measure VSWM in ADHD adolescents. The Rey-Osterrieth complex figure test (ROCF) is commonly used as a neuropsychological test to assess visuospatial working memory for individuals with ADHD. We assessed working memory using the ROCF test on a digital Galaxy tablet with the technically new Gaussian filter method. METHODS Thirty adolescents with ADHD and 30 healthy control adolescents were recruited for participation in the current study. All adolescents were assessed with K-WISC-IV, Childrens depression inventory, and the Korean ADHD rating scale. All adolescents were asked to copy the ROCF from paper onto a Galaxy tablet screen using a wireless pen. RESULTS There was a significant difference in representative value of the deviation of the original images from template images (R-value) in copy and delayed recall between ADHD adolescents and healthy adolescents. There was no significant difference in R-value of immediate recall between ADHD adolescents and healthy adolescents. In all adolescents (ADHD and healthy) and ADHD adolescents, the R-value of copy was negatively correlated with visuospatial index and working memory index, and the R-value of delayed recall was negatively correlated with WMI. The R-value of copy and delayed recall was positively correlated with K-ARS in all adolescents and ADHD adolescents. CONCLUSIONS ADHD adolescents showed differences in the R-values of copy and delayed recall in the digital ROCF version compared to healthy adolescents. The digital ROCF assessment tool can represent different patterns of visuospatial working memory abilities in ADHD adolescents compared to healthy adolescents.
Neuropathology of Drug Addictions and Substance Misuse#R##N#Volume 3: General Processes and Mechanisms, Prescription Medications, Caffeine and Areca, Polydrug Misuse, Emerging Addictions and Non-Drug Addictions | 2016
Doug Hyun Han; Gi Jung Hyun; Jeong Ha Park; Perry F. Renshaw
Internet games are receiving considerable attention due to their multifaceted nature including recreational applications, improved graphics, early clinical applications, and concerns regarding clinical side effects due to excessive play. This chapter reviews the results of functional and structural brain changes, neurophysiological responses, and biogenetic traits in individuals with Internet gaming disorder (IGD). IGD and substance addiction appear to share common activated brain regions including corticostriatal tracts in response to game or substance cues. In addition, neurophysiological responses such as poor error processing as well as association with dopamine and serotonin have been observed in both impulse control disorder and behavioral addictions. However, the use of inconsistent diagnostic criteria across studies, variable demographic characteristics, high rates of psychiatric comorbidity, and uncertain courses of disease require further research.
Journal of Alternative and Complementary Medicine | 2016
Gi Jung Hyun; Tae-Woon Jung; Jeong Ha Park; Kyoung Doo Kang; Sun Mi Kim; Jae Hoon Cheong; Bung-Nyun Kim; Doug Hyun Han
OBJECTIVES Equine-assisted activity and training (EAAT) is thought to improve body balance and clinical symptoms in children with attention deficit hyperactivity disorder (ADHD). The study hypostheses were that EAAT would improve the clinical symptoms and gait balance in children with ADHD and that these improvements would be associated with increased brain connectivity within the balance circuit. METHODS A total of 12 children with ADHD and 12 age- and sex-matched healthy control children were recruited. EAAT consisted of three training sessions, each 70 minutes long, once a week for 4 weeks. Brain functional connectivity was assessed by using functional magnetic resonance imaging. RESULTS After 4 weeks of EAAT, children with ADHD showed improved scores on the Korean ADHD scale (K-ARS), while the K-ARS scores of healthy children did not change. During the 4 weeks, the plantar pressure difference between the left foot and right foot decreased in both the healthy control group and the ADHD group. After 4 weeks of EAAT, healthy controls showed increased brain connectivity from the cerebellum to the left occipital lingual gyrus, fusiform gyrus, right and left thalami, right caudate, right precentral gyrus, and right superior frontal gyrus. However, children with ADHD showed increased brain connectivity from the cerebellum to the right insular cortex, right middle temporal gyrus, left superior temporal gyrus, and right precentral gyrus. In contrast, children with ADHD exhibited decreased brain connectivity from the cerebellum to the left inferior frontal gyrus. CONCLUSION EAAT may improve clinical symptoms, gait balance, and brain connectivity, the last of which controls gait balance, in children with ADHD. However, children with ADHD who have deficits in the fronto-cerebellar tract did not exhibit changes in brain connectivity as extensive as those in healthy children in response to EAAT.
Journal of the Korean Academy of Child and Adolescent Psychiatry | 2016
Sumin Lee; Jae-Won Choi; Kyoungmin Kim; Jun Won Kim; Sooyeon Kim; Tae-Woong Kang; Johanna Inhyang Kim; Young Sik Lee; Bongseog Kim; Doug Hyun Han; Jae Hoon Cheong; So-Young Lee; Gi Jung Hyun; Bung-Nyun Kim
Journal of the Korean Academy of Child and Adolescent Psychiatry | 2015
Jeong Ha Park; Gi Jung Hyun; Ji Hyun Son; Young Sik Lee
Journal of the American Academy of Child and Adolescent Psychiatry | 2016
Doug Hyun Han; Jeongha Park; Gi Jung Hyun; Sun Mi Kim; Perry F. Renshaw
Journal of Korean Neuropsychiatric Association | 2016
Gi Jung Hyun; Bongseog Kim; Bung-Nyun Kim; Johanna Inhyang Kim; Jeong Ha Park; Geon Ho Bahn; Moon-Soo Lee; So-Young Lee; Young Sik Lee; Doug Hyun Han