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Psychiatry and Clinical Neurosciences | 2004

Attention deficit hyperactivity symptoms and Internet addiction

Hee Jeong Yoo; Soo Churl Cho; Jihyun Ha; Sook Kyung Yune; Seog Ju Kim; Jaeuk Hwang; Ain Chung; Young Hoon Sung; In Kyoon Lyoo

Abstract  The objective of this study was to evaluate the relationship between attention deficit‐hyperactivity/impulsivity symptoms and Internet addiction. In total, 535 elementary school students (264 boys, 271 girls; mean age, 11.0 ± 1.0 years) were recruited. The presence or severity of Internet addiction was assessed by the Youngs Internet Addiction test. Parents and teachers of the children completed the DuPauls attention deficit hyperactivity disorder (ADHD) rating scale (ARS; Korean version, K‐ARS) and Child Behavior Checklists. Children with the highest and lowest quartiles in K‐ARS scores were defined to be in ADHD and non‐ADHD groups, respectively. Five children (0.9%) met criteria for a definite Internet addiction and 75 children (14.0%) met criteria for a probable Internet addiction. K‐ARS scores had significant positive correlations with Youngs Internet Addiction test scores. The Internet addiction group had higher total scores of K‐ARS and ADHD‐related subcategories in the Child Behavior Checklists than the non‐addiction group. The ADHD group had higher Internet addiction scores compared with the non‐ADHD group. Therefore, significant associations have been found between the level of ADHD symptoms and the severity of Internet addiction in children. In addition, current findings suggest that the presence of ADHD symptoms, both in inattention and hyperactivity‐impulsivity domains, may be one of the important risk factors for Internet addiction.


Psychopathology | 2007

Depression and Internet Addiction in Adolescents

Jee Hyun Ha; Su Yeon Kim; Soojeong C. Bae; Sujin Bae; Hyung-Jun Kim; Minyoung Sim; In Kyoon Lyoo; Soo Churl Cho

Background: The aim of the study was to evaluate the relationship between depression and Internet addiction among adolescents. Sampling and Method: A total of 452 Korean adolescents were studied. First, they were evaluated for their severity of Internet addiction with consideration of their behavioral characteristics and their primary purpose for computer use. Second, we investigated correlations between Internet addiction and depression, alcohol dependence and obsessive-compulsive symptoms. Third, the relationship between Internet addiction and biogenetic temperament as assessed by the Temperament and Character Inventory was evaluated. Results: Internet addiction was significantly associated with depressive symptoms and obsessive-compulsive symptoms. Regarding biogenetic temperament and character patterns, high harm avoidance, low self-directedness, low cooperativeness and high self-transcendence were correlated with Internet addiction. In multivariate analysis, among clinical symptoms depression was most closely related to Internet addiction, even after controlling for differences in biogenetic temperament. Conclusions: This study reveals a significant association between Internet addiction and depressive symptoms in adolescents. This association is supported by temperament profiles of the Internet addiction group. The data suggest the necessity of the evaluation of the potential underlying depression in the treatment of Internet-addicted adolescents.


Biological Psychiatry | 2004

Frontal lobe gray matter density decreases in bipolar I disorder.

In Kyoon Lyoo; Minue J. Kim; Andrew L. Stoll; Christina Demopulos; Aimee Parow; Stephen R. Dager; Seth D. Friedman; David L. Dunner; Perry F. Renshaw

BACKGROUND This study was conducted to explore differences in gray and white matter density between bipolar and healthy comparison groups using voxel-based morphometry (VBM). METHODS Brain magnetic resonance imaging was performed for 39 subjects with bipolar I disorder and 43 comparison subjects. Images were registered into a proportional stereotaxic space and segmented into gray matter, white mater, and cerebrospinal fluid. Statistical parametric mapping was used to calculate differences in gray and white matter density between groups. RESULTS Bipolar subjects had decreased gray matter density in left anterior cingulate gyrus (Brodmanns area [BA] 32, 7.3% decrease), an adjacent left medial frontal gyrus (BA 10, 6.9% decrease), right inferior frontal gyrus (BA 47, 9.2% decrease), and right precentral gyrus (BA 44, 6.2% decrease), relative to comparison subjects. CONCLUSIONS The observation of a gray matter density decrease in the left anterior cingulate, which processes emotions, in bipolar subjects is consistent with prior reports that used region-of-interest analytic methods. Decreased gray matter density in the right inferior frontal gyrus, which processes nonverbal and intrinsic functions, supports nondominant hemisphere dysfunction as a component of bipolar disorder.


Psychiatry Research-neuroimaging | 2003

Neural correlates of clinical symptoms and cognitive dysfunctions in obsessive-compulsive disorder.

Jun Soo Kwon; Jae-Jin Kim; Dong Woo Lee; Jae Sung Lee; Dong Soo Lee; In Kyoon Lyoo; Maeng Je Cho; Myung Chul Lee

Although results from neuropsychological and neuroimaging studies have postulated the involvement of the frontal lobe and the subcortical brain regions in the pathophysiology of obsessive-compulsive disorder (OCD), neuroimaging studies have provided little evidence that cognitive abnormalities in patients with OCD are related to dysfunctions in these areas. This study was designed to determine whether the clinical features and cognitive deficits of OCD might be taken to reflect frontal-subcortical dysfunction. Fourteen patients with OCD and 14 case-matched normal subjects completed clinical and cognitive evaluation, including four sets of neuropsychological tests that assessed the executive functions and visual memory. Cerebral glucose metabolic rates were measured by using positron emission tomography (PET) with 18F-fluorodeoxyglucose. Behavioral and PET data were analyzed using statistical parametric mapping for group differences and behavioral-metabolic correlates. The right orbitofrontal cortex showed increased metabolic activity and the left parieto-occipital junction showed decreased metabolic activity in patients. Metabolism in the right hippocampus, the left putamen and the right parietal region was associated with the severity of obsessive-compulsive symptoms. Correlations between metabolic rates and neuropsychological test scores in the prefrontal cortex and the putamen occurred only in the patient group. These results suggest that patients with OCD have distinct features of brain metabolic activities for performing cognitive tasks as well as presenting obsessive-compulsive symptoms. In particular, the frontal-subcortical circuits might mediate not only symptomatic expression but also cognitive expression in patients with OCD.


Neuropsychopharmacology | 2007

Cerebellar Gray Matter Volume Correlates with Duration of Cocaine Use in Cocaine-Dependent Subjects

Minyoung Sim; In Kyoon Lyoo; Chris C. Streeter; Julie Covell; Ofra Sarid-Segal; Domenic A. Ciraulo; Minue J Kim; Marc J. Kaufman; Deborah A. Yurgelun-Todd; Perry F. Renshaw

This study was conducted to explore differences in gray and white matter volume between cocaine-dependent and healthy comparison subjects using optimized voxel-based morphometry (VBM). Brain magnetic resonance imaging (MRI) and neuropsychological function tests were performed for 40 cocaine-dependent subjects (41.4±6.9 years, 27 men) and 41 healthy age- and sex-matched comparison subjects (38.7±8.8 years, 26 men). Optimally normalized whole brain MR images were segmented, modulated, smoothed, and compared between groups with statistical parametric mapping. The cocaine-dependent group had lower gray matter volumes in bilateral premotor cortex (Brodmann area (BA) 6, 8; 16.6%), right orbitofrontal cortex (BA 10, 15.1%), bilateral temporal cortex (BA 20, 38; 15.9%), left thalamus (12.6%), and bilateral cerebellum (13.4%) as well as lower right cerebellar white matter volume (10.0%) relative to the comparison group at a corrected p<0.05 for multiple comparisons. Duration of cocaine use negatively correlated with right and left cerebellar gray matter volumes (r=−0.37, r=−0.39, respectively). In cocaine-dependent subjects, lower cerebellar hemispheric gray and white matter volumes were correlated with deficits in executive function and decreased motor performance. This study reports that cocaine-dependent subjects have lower gray matter volumes in cerebellar hemispheres as well as in frontal, temporal cortex, and thalamus. These findings are the first to suggest that the cerebellum may be vulnerable to cocaine-associated brain volume changes, and that cerebellar deficits may contribute to neuropsychological deficits and motor dysfunction frequently observed in cocaine-dependent subjects.


Neuropsychopharmacology | 2010

Lithium-induced gray matter volume increase as a neural correlate of treatment response in bipolar disorder: a longitudinal brain imaging study.

In Kyoon Lyoo; Stephen R. Dager; Ji-Eun Kim; Sujung J. Yoon; Seth D. Friedman; David L. Dunner; Perry F. Renshaw

Preclinical studies suggest that lithium may exert neurotrophic effects that counteract pathological processes in the brain of patients with bipolar disorder (BD). To describe and compare the course and magnitude of gray matter volume changes in patients with BD who are treated with lithium or valproic acid (VPA) compared to healthy comparison subjects, and to assess clinical relationships to gray matter volume changes induced by lithium in patients with BD, we conducted longitudinal brain imaging and clinical evaluations of treatment response in 22 mood-stabilizing and antipsychotic medications-naive patients with BD who were randomly assigned to either lithium or VPA treatment after baseline assessment. Fourteen healthy comparison subjects did not take any psychotropic medications during follow-up. Longitudinal data analyses of 93 serial magnetic resonance images revealed lithium-induced increases in gray matter volume, which peaked at week 10–12 and were maintained through 16 weeks of treatment. This increase was associated with positive clinical response. In contrast, VPA-treated patients with BD or healthy comparison subjects did not show gray matter volume changes over time. Results suggest that lithium induces sustained increases in cerebral gray matter volume in patients with BD and that these changes are related to the therapeutic efficacy of lithium.


Journal of Affective Disorders | 1998

A brain MRI study in subjects with borderline personality disorder

In Kyoon Lyoo; Moon Hee Han; Doo Young Cho

BACKGROUND There have been only a few brain computed tomography imaging studies, with mostly negative findings, in subjects with borderline personality disorder (BPD). This is the first MRI study which evaluated the structural abnormalities of the brain in subjects with the sole diagnosis of BPD. METHODS Twenty-five subjects with BPD were compared with age-, gender-matched healthy comparison subjects (n=25) on volumes of the frontal lobes, the temporal lobes, the lateral ventricles, and the cerebral hemispheres in brain magnetic resonance imaging. RESULTS Subjects with BPD had a significantly smaller frontal lobe compared to comparison subjects (multivariate regression analysis, t=2.225, df=46, P=0.031). There were no significant differences in volumes of the temporal lobes, the lateral ventricles, and the cerebral hemispheres between subjects with and without BPD. LIMITATIONS Strict inclusion and exclusion criteria employed in the present study may make it difficult to generalize our findings. The gray matter and white matter of the brain were not measured separately. Differences in head tilt during image acquisition were not corrected. CONCLUSIONS The current study reports a smaller frontal lobe volume on brain MRI in subjects with BPD compared with healthy comparison subjects. This finding may serve as a potentially useful biological variable that may allow for subtyping BPD.


Psychopharmacology | 2006

Prefrontal and temporal gray matter density decreases in opiate dependence

In Kyoon Lyoo; Mark H. Pollack; Marisa M. Silveri; Kyung-Heup Ahn; Claudia I. Diaz; Jaeuk Hwang; Seog Ju Kim; Deborah A. Yurgelun-Todd; Marc J. Kaufman; Perry F. Renshaw

RationaleThere have been only a few structural brain-imaging studies, with varied findings, of opiate-dependent subjects. Voxel-based morphometry (VBM) is suitable for studying whole brain-wise structural brain changes in opiate-dependent subjects.ObjectivesThe objective of the current study is to explore gray matter density in opiate-dependent subjects.MethodsGray matter density in 63 opiate-dependent subjects and 46 age- and sex-matched healthy comparison subjects was compared using VBM.ResultsRelative to healthy comparison subjects, opiate-dependent subjects exhibited decreased gray matter density in bilateral prefrontal cortex [Brodmann areas (BA) 8, 9, 10, 11, and 47], bilateral insula (BA 13), bilateral superior temporal cortex (BA 21 and 38), left fusiform cortex (BA 37), and right uncus (BA 28).ConclusionsThis study reports that opiate-dependent subjects have gray matter density decreases in prefrontal and temporal cortex, which may be associated with behavioral and neuropsychological dysfunction in opiate-dependent subjects.


Journal of Addiction Medicine | 2007

Dopamine genes and reward dependence in adolescents with excessive internet video game play.

Doug Hyun Han; Young Sik Lee; Kevin Yang; Eun Young Kim; In Kyoon Lyoo; Perry F. Renshaw

Excessive internet video game play (EIGP) has emerged as a leading cause of behavioral and developmental problems in adolescents. Recent research has implicated the role of striatal dopaminergic system in the behavioral maladaptations associated with EIGP. This study investigates the reward-dependence characteristics in EIGP adolescents as it potentially relates to genetic polymorphisms of the dopaminergic system and temperament. Seventy-nine male EIGP adolescents and 75 age- and gender-matched healthy comparison adolescents were recruited. Associations were tested with respect to the reward-dependence (RD) scale in Cloninger’s Temperament and Character Inventory and the frequencies of 3 dopamine polymorphisms: Taq1A1 allele of the dopamine D2 receptor (DRD2 Taq1A1) and Val158Met in the Catecholamine-O-Methyltransferase (COMT) genes. The Taq1A1 and low activity (COMTL) alleles were significantly more prevalent in the EIGP group relative to the comparison group. The present EIGP group had significantly higher RD scores than controls. Within the EIGP group, the presence of the Taq1A1 allele correlated with higher RD scores. Our findings suggest that EIGP subjects have higher reward dependency and an increased prevalence of the DRD2 Taq1A1 and COMTL alleles. In particular, the DRD2 Taq1A1 allele seems to be associated with reward dependence in EIGP adolescents.


Biological Psychiatry | 1996

The corpus callosum and lateral ventricles in children with attention-deficit hyperactivity disorder: A brain magnetic resonance imaging study

In Kyoon Lyoo; Gil G. Noam; Chang K. Lee; Ho K. Lee; Bruce P. Kennedy; Perry F. Renshaw

There has been an increasing interest in alterations of corpus callosum (CC) morphology in children with attention-deficit hyperactivity disorder (ADHD), since abnormalities in specific areas of the CC may reflect differences in corresponding regions of the brain from which interhemispheric fibers originate (Giedd et al 1994; Hynd et al 1991; Semrud-Clikeman et al 1994). Results reported to date have been inconsistent (Giedd et al 1994; Hynd et al 1991; Semrud-Clikeman et al 1994), and these divergent findings may arise from several sources, including different diagnostic inclusion criteria for a disorder with extensive comorbidity, different comparison populations, and different age or gender composition of the study populations. We now report on the area of the CC and its seven subdivisions in a large number of children with ADHD (n = 51). In addition, we have measured the volume of the anterior and posterior lateral ventricles (LV) in this population, as we hypoth-

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Seog Ju Kim

Seoul National University

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Jaeuk Hwang

Soonchunhyang University

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Sujung J. Yoon

Catholic University of Korea

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Ji-Eun Kim

Ewha Womans University

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Jun Soo Kwon

Seoul National University

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Minyoung Sim

Seoul National University

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