Bungnyun Kim

Seoul National University | SNU · Division of Child & Adolescent Psychiatry and Center for NDDs translational Research

Disclosure: Y. Lee: None. K. Lee: None. J. Kim: None. Y. Lim: None. J.I. Kim: None. B. Kim: None. Y. Hong: None. J. Song: None. C. Shin: None. Y. Lee: None. Background: 11-oxygenated androgens (11-oxyandrogens) have been recognized for their important role in adrenarche or androgen excess conditions. However, the trajectory during childhood remains...

With the global increase in life expectancy, there has been a rise in the incidence of cognitive impairments attributed to diverse etiologies. Notably, approximately 50% of individuals diagnosed with mild cognitive impairment (MCI) progress to dementia within 3 years. However, the precise mechanisms underlying MCI remain elusive. Therefore, this st...

This study utilized arterial spin labeling-magnetic resonance imaging (ASL-MRI) to explore the developmental trajectory of brain activity associated with attention deficit hyperactivity disorder (ADHD). Pulsed arterial spin labeling (ASL) data were acquired from 157 children with ADHD and 109 children in a control group, all aged 6–12 years old. Pa...

The neurodevelopmental outcomes of preterm infants can be stratified based on the level of prematurity. We explored brain structural networks in extremely preterm (EP; < 28 weeks of gestation) and very-to-late (V-LP; ≥ 28 and < 37 weeks of gestation) preterm infants at term-equivalent age to predict 2-year neurodevelopmental outcomes. Using MRI and...

Objectives Non-suicidal self-injury (NSSI) and suicidal behavior, including suicidal ideation (SI) and suicide attempts, are important predictors of suicide in adolescents. This study aimed to investigate the associations between NSSI, SI, NSSI+SI, mental health problems, and family factors in Korean adolescents in Jeju Island, with an emphasis on...

Aberrant intrinsic brain networks are consistently observed in individuals with autism spectrum disorder. However, studies examining the strength of functional connectivity across brain regions have yielded conflicting results. Therefore, this study aimed to investigate the functional connectivity of the resting brain in children with low-functioni...

This study utilized Arterial Spin Labeling-Magnetic Resonance Imaging (ASL-MRI) to explore the developmental trajectory of brain activity associated with attention deficit hyperactivity disorder (ADHD). Pulsed arterial spin labeling (PASL) data were acquired from 109 children with ADHD and 58 children in a control group, all aged 6–12 years old. Pa...

Determine brain structural networks in extremely preterm (EP; <28 weeks), very-to-late preterm (V-LP; ≥28 and < 37 weeks), and all preterm infants at term-equivalent age. Predict 2-year neurodevelopmental scores using multimodal predictors. Prospective cross-sectional study with MRI and diffusion MRI on 61 EP and 131 V-LP infants. Constructed a mul...

Parents of children with autism spectrum disorder (ASD) often encounter unique challenges when attempting to understand their children’s challenging behaviors such as self-injury, aggression, noncompliance, and stereotypies. In this study, we aimed to analyze and clarify the definition of challenging behaviors in individuals with ASD, identify the...

Under the Ministry of Health and Welfare of the Republic of Korea, the National Autism and Developmental Disorder Centers for people with developmental disabilities are gradually expanding. The headquarters of the National Autism and Developmental Disorder Center provides support for education, training, and research, and several centers have been...

Introduction Since the Coronavirus disease 2019 (COVID-19), public safety measures, including social distancing and school closures, have been implemented, precipitating psychological difficulties and heightened online activities for adolescents. However, studies examining the impact of the pandemic on adolescent mental health and their coping stra...

Objective: Adequate iodine intake is essential for growing children, and thyroid volume (Tvol) is considered as an indicator of iodine status. We investigated Tvol and goiter using ultrasonography (US) and their association with iodine status in 228 6-year-old children living in Korea. Methods: Iodine status was assessed using urine iodine concentr...

Objectives This study aimed to assess the status of the Journal of the Korean Academy of Child and Adolescent Psychiatry (JKACAP) and propose measures for its growth and development. Methods The study was conducted using a questionnaire survey targeting members of the Korean Academy of Child and Adolescent Psychiatry. The six key elements analyzed...

Objective: : To examine the effect of mobile neurofeedback training on the clinical symptoms, attention abilities, and execution functions of children with attention deficit hyperactivity disorder (ADHD). Methods: : The participants were 74 children with ADHD aged 8-15 years who visited the Department of Child and Adolescent Psychiatry at Seoul...

Objective Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children and adults characterized by cognitive and emotional self-control deficiencies. Previous functional near-infrared spectroscopy (fNIRS) studies found significant group differences between ADHD children and healthy controls during cognitive fl...

Epigenetic influence plays a role in the association between exposure to air pollution and attention deficit hyperactivity disorder (ADHD); however, research regarding sulfur dioxide (SO2) is scarce. Herein, we investigate the associations between prenatal SO2 exposure and ADHD rating scale (ARS) at ages 4, 6 and 8 years repeatedly in a mother–chil...

Importance: Postnatal growth may be associated with longitudinal brain development in children born preterm. Objective: To compare brain microstructure and functional connectivity strength with cognitive outcomes in association with postnatal growth among early school-aged children born preterm with extremely low birth weight. Design, setting,...

There is evidence that exposure to perfluoroalkyl substances (PFAS) is associated with attention-deficit/hyperactivity disorder (ADHD) symptoms. Previous studies have focused on prenatal exposure to PFAS, and only few studies have examined the associations of early-childhood exposure, especially at low exposure levels. This study explored the assoc...

Background Adequate iodine intake is essential for growing children, as both deficient and excessive iodine status can result in thyroid dysfunction. We investigated the iodine status and its association with thyroid function in 6-year-old children from South Korea. Methods A total of 439 children aged 6 (231 boys and 208 girls) were investigated...

There are three presentations of attention-deficit/hyperactivity disorder (ADHD): the predominantly inattention (ADHD-PI), predominantly hyperactive-impulsive (ADHD-HI), and combined (ADHD-C) presentations of ADHD. These may represent distinct childhood-onset neurobehavioral disorders with separate etiologies. ADHD diagnoses are behaviorally based,...

Children with attention-deficit/hyperactivity disorder (ADHD) often struggle with impaired executive function, temporal processing, and visuospatial memory, hallmarks of the predominantly inattentive presentation (ADHD-PI), subserved by the hippocampus. However, the specific genes/proteins involved and how they shape hippocampal structures to influ...

[This corrects the article on p. 71 in vol. 32, PMID: 33828406.].

[This corrects the article on p. 67 in vol. 33, PMID: 35832862.].

Objectives: Tic disorders are highly heritable; however, growing evidence suggests that environmental factors play a significant role in their pathogenesis. Studies on these factors have been inconsistent, with conflicting results. Therefore, this study aimed to examine the associations of pre- and perinatal exposure to Tourette syndrome (TS) or c...

Objective: Underconnectivity in the resting brain is not consistent in autism spectrum disorder (ASD). However, it is known that the functional connectivity of the default mode network is mainly decreased in childhood ASD. This study investigated the brain network topology as the changes in the connection strength and network efficiency in childho...

Objective: This research measures the regional GMV (rGMV) of the cerebellum, attention, Executive Function (EF) and we aimed to identify their correlation and sex differences in children and adolescents. Methods: Subjects comprised 114 children (male = 62, female = 52, 12.44 ± 2.99 years old) from South Korea. Participants were divided into thre...

Objective: Suicide attempts (SAs) in adolescents are difficult to predict although it is a leading cause of death among adolescents. This study aimed to develop and evaluate SA prediction models based on six different machine learning (ML) algorithms for Korean adolescents using data from online surveys. Methods: Data were extracted from the 201...

BACKGROUND Mindfulness-based training programs are known to be effective in reducing stress levels. OBJECTIVE This study examines the effectiveness of a 4-week neurofeedback-assisted mindfulness-based training program delivered via a mobile application for employees. METHODS Participants (n = 92) with a full-time job were assigned to one of three...

Background Mindfulness-based training programs have consistently shown efficacy in stress reduction. However, questions regarding the optimal duration and most effective delivery methods remain. Objective This research explores a 4-week neurofeedback-assisted mindfulness training for employees via a mobile app. The study’s core query is whether inc...

Despite the predominance and high heritability of attention-deficit/hyperactivity disorder (ADHD), its etiology remains unclear. Preclinical and clinical evidence partially implicates impaired limbic system function, particularly in the hippocampus (HPC). Children diagnosed with ADHD often struggle with deficits in executive function, temporal proc...

Machine learning algorithms have been widely applied in diagnostic tools for autism spectrum disorder (ASD), revealing an altered brain connectivity. However, little is known about whether an magnetic resonance imaging (MRI)-based brain network is related to the severity of ASD symptoms in a large-scale cohort. We propose a graph convolution neural...

Several individuals worldwide show cognitive impairment due to various reasons, including a prolonged lifespan and an altered lifestyle. Various causes, such as broken circadian rhythms and dopamine-related factors, have been proposed to be involved in the development of cognitive impairment. However, the underlying pathways remain elusive. Humans...

Objectives: This study investigated the reliability and validity of the Korean version of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) Level 2 Cross-Cutting Symptom Measure-Patient-Reported Outcomes Measurement Information System (PROMIS)-Depression and the Irritability for parents of children aged 6-17 years....

Background Hyperuricemia has a suspected relationship with hypertension, metabolic syndrome, kidney disease, and cardiovascular disease. Endocrine disruptors may affect uric acid metabolism; however, few epidemiologic studies have been performed in children regarding newly developed bisphenol A (BPA) substitutes. We evaluated the associations betwe...

While thyroid disturbances during perinatal and postnatal periods in preterm infants with congenital hypothyroidism reportedly disrupt neuronal development, no study has considered the effect of thyroid disturbances in premature infants with subclinical hypothyroidism with elevations of thyroid stimulating hormone. We aimed to identify altered fibe...

Preterm births are often associated with neurodevelopmental impairment. In the critical developmental period of the fetal brain, preterm birth disrupts cortical maturation. Notably, preterm birth leads to alterations in the fronto-striatal and temporal lobes and the limbic region. Recent advances in MRI acquisition and analysis methods have reveale...

Backgrounds: Epigenetic influence plays a role in the association between exposure to air pollution and attention deficit hyperactivity disorder (ADHD); however, research regarding sulfur dioxide (SO2) is scarce. Herein, we investigate the associations between prenatal SO2 exposure and ADHD rating scale (ARS) scores at ages 4, 6, and 8 years repeat...

Backgrounds : Epigenetic influence plays a role in the association between exposure to air pollution and attention deficit hyperactivity disorder (ADHD); however, research regarding sulfur dioxide (SO2) is scarce. Herein, we investigate the associations between prenatal SO2 exposure and ADHD rating scale (ARS) scores at ages 4, 6, and 8 years repea...

Neurodevelopmental disorder (NDD) in preterm infants has become of great interest. We aimed to investigate the impact of preterm birth on the proportion of NDD using nationwide data provided by the Korean National Health Insurance Service. We included 4894 extremely preterm or extremely low-birth-weight (EP/ELBW; <28 weeks of gestation or birth wei...

Challenging behaviors significantly impact learning and socialization of autistic children and can stress and burden their caregivers. Documentation of challenging behaviors is fundamental for identifying what environmental factors influence them, such as how others respond to a child's such behaviors. Caregiver-tracked data on their child's challe...

Background Bisphenol A (BPA) has been linked to attention-deficit/hyperactivity disorder (ADHD) symptoms, but the neurotoxic effects of bisphenol substitutes such as bisphenol F (BPF) and S (BPS) have not been well investigated. We investigated the associations between BPA, BPF, and BPS with ADHD symptoms at multiple time points in children. Metho...

Background Pyrethroid insecticides are commonly used in residential settings, and their use has increased rapidly. Although research has been scarce, they have been reported to be associated with impaired neurodevelopment. Moreover, susceptible exposure windows and the long-term effects of pyrethroids have not been investigated. We examined the ass...

Multimodal imaging studies targeting preschoolers and low-functioning autism spectrum disorder (ASD) patients are scarce. We applied machine learning classifiers to parameters from T1-weighted MRI and DTI data of 58 children with ASD (age 3–6 years) and 48 typically developing controls (TDC). Classification performance reached an accuracy, sensitiv...

Maternal adverse childhood experiences (ACEs) may negatively affect the mental health and development of their offspring. The purpose of this study was to investigate the association of maternal ACE and offspring’s psychiatric disorder and the mediating effect of maternal depression. The subjects included 463 mothers (42.78 ± 5.68 years) and their...

Background Underconnectivity in the resting brain is not consistent in autism spectrum disorder (ASD). However, it is known that the default mode network is mainly decreased in childhood ASD. This study investigated the brain network topology as the changes in the connection strength and network efficiency in childhood ASD, including the early deve...

Background Phthalates are synthetic chemicals with endocrine-disrupting properties. They are reportedly associated with various neurotoxic outcomes. Studies on exposure to phthalates and children’s autistic traits have shown inconsistent results with respect to sex and susceptible time periods. We investigated the association of phthalate exposure...

Background Humans are exposed to a mixture of metals during their lifetime; however, evidence of neurotoxicity of such mixtures in critical time windows is still insufficient. We aimed to elucidate the associations of four metals mixture across multiple time points with children’s intelligence quotient (IQ) in a prospective cohort study. Methods P...

Objective: Adverse childhood experiences (ACEs) are associated with negative physical and mental health outcomes across the lifespan, but research on intergenerational transmission of maternal ACEs and its impact on the offspring's mental health problems are limited. The study examines the effects of maternal ACEs on the risk of internalizing or e...

Background: School-aged children born very preterm have been suggested to have worse cognitive and behavioral outcomes than children born full-term. Executive function (EF) is a higher level of cognitive function related to academic achievement. The present study aimed to evaluate the cognitive (including EF) and behavioral outcomes of Korean chil...

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder, potentially with a biological basis; however, its exact cause remains unknown. Thyroid hormone (TH) abnormalities are more prevalent in patients with ADHD than in the general population, indicating a shared pathogenetic mechanism for these conditions. Previously, we i...

Background and objective Global Lung Function Initiative (GLI) 2012 equations were developed to resolve the age-related disparity in interpreting spirometry results. Local validation of the equation is needed, especially in Northeast Asian children. This study evaluated the GLI equation in Korean children. Methods Spirometry indices (FEV1, FVC, FE...

The hippocampus, which engages in the process of consolidating long-term memories and learning, shows active development during childhood and adolescence. The hippocampus also functionally influences attention. Based on the influence of hippocampal function on attention, it was expected that the volume of the hippocampus would be associated with th...

Childhood obesity could contribute to adulthood obesity, leading to adverse health outcomes in adults. However, the mechanisms for how obesity is developed are still unclear. To determine the epigenome-wide and genome-wide expression changes related with childhood obesity, we compared microRNome and transcriptome levels as well as leptin protein le...

Background: During late childhood and adolescence, the frontal lobe undergoes critical developmental changes, affecting a wide range of executive functions significantly. Conversely, abnormality in the maturation of the frontal lobe during this period may result in a limited ability to effectively use various executive functions. However, at presen...

Epigenetics is known to be involved in regulatory pathways through which greenness exposure influences child development and health. We aimed to investigate the associations between residential surrounding greenness and DNA methylation changes in children, and further assessed the association between DNA methylation and children’s intelligence quot...

Objectives: Childhood adversity is a risk factor for anxiety symptoms, but it affects anxiety symptoms in attention-deficit/hyperactivity disorder (ADHD). The current study aimed to examine the association between childhood adversity and anxiety symptoms in participants with and without ADHD. Methods: Data were obtained from a school-based epide...

Background Sufficient sleep during childhood is important for cognitive functions such as learning and successful school performance. This study aimed to investigate the effects of sleep duration on the intelligence quotient (IQ) of 6-year-old children and aimed to analyze whether these effects differed by sex.Methods The IQ of 538 6-year-old Korea...

Introduction: Adiposity rebound (AR) refers to the increase in body mass index (BMI) that follows the BMI nadir in childho