Jeanyung Chey

Seoul National University | SNU · Department of Psychology

Education involves learning new information and acquiring cognitive skills. These require various cognitive processes including learning, memory, and language. Since cognitive processes activate associated brain areas, we proposed that the brains of elderly people with longer education periods would show traces of repeated activation as increased s...

Previous brain imaging studies have reported hyperactivation of the amygdala and hypoactivation of the anterior cingulate in posttraumatic stress disorder (PTSD) patients, which is believed to be an underlying neural mechanism of the PTSD symptoms. The current study specifically focuses on the abnormal activity of the rostral anterior cingulate, us...

The Clock Drawing Test (CDT) has been recognized as an effective tool for dementia detection. This study investigated the clock drawing performance of 240 non-demented elderly Korean people with a wide-range of educational levels and 28 patients with mild dementia of the Alzheimer's type (DAT). We examined the effects of demographic factors, includ...

Poor cognitive performance of elderly individuals with low educational attainment is often difficult to interpret in dementia evaluation. Lack of education, as well as dementia, is often associated with poor cognitive test performance. To elucidate the underlying structural change of low cognitive performance in elderly individuals with low educati...

Adaptive decision making in dynamic social settings requires frequent re-evaluation of choice outcomes and revision of strategies. This requires an array of multiple cognitive abilities, such as working memory and response inhibition. Thus, the disruption of such abilities in schizophrenia can have significant implications for social dysfunctions i...

- The Korean Proverb test demonstrated favorable psychometric properties, including high internal consistency, discriminant and convergent validity - Performance was associated with the degree of literacy, even among older adults with low education, supporting the test's applicability to this population with minimized floor effect - The neural corr...

- Psychological Well-Being was systematically related with cognitive and daily living functioning of older adults. - Lower Psychological Well-Being may be associated with heightened sensitivity to threat stimuli, as indicated by increased connectivity between the amygdala and proximal emotion-related regions, along with decreased connectivity betwe...

In this study, we developed a proverb test as a measure for assessing higher-order cognitive functions in Korean older adults and explored its psychometric properties. Specifically, we aimed to investigate the applicability of the proverb test as a measure for conceptualization ability within the context of predominantly low-educated elderly popu...

Cognitive Reserve (CR) refers to the individual’s neuropsychological properties that enable better cognitive performance than what is expected based on current levels of brain resources or pathology. Aging is often accompanied by pathological changes such as a brain atrophy as well as the accumulation of neural plaques or neurofibrillary tangles, l...

Loneliness has an important impact on memory function in late life. However, the neural mechanism by which loneliness detrimentally influences memory function remains elusive. Furthermore, it remains unclear whether the association between loneliness and memory function varies by gender. The current study aimed to investigate the neural mechanism u...

Society within the Brain provides insightful accounts of scientific research linking social connection with brain and cognitive aging through state-of-the-art research. This involves comprehensive social network analysis, social neuroscience, neuropsychology, psychoneuroimmunology, and sociogenomics. This book provides a scientific discourse on how...

Society within the Brain provides insightful accounts of scientific research linking social connection with brain and cognitive aging through state-of-the-art research. This involves comprehensive social network analysis, social neuroscience, neuropsychology, psychoneuroimmunology, and sociogenomics. This book provides a scientific discourse on how...

Society within the Brain provides insightful accounts of scientific research linking social connection with brain and cognitive aging through state-of-the-art research. This involves comprehensive social network analysis, social neuroscience, neuropsychology, psychoneuroimmunology, and sociogenomics. This book provides a scientific discourse on how...

Society within the Brain provides insightful accounts of scientific research linking social connection with brain and cognitive aging through state-of-the-art research. This involves comprehensive social network analysis, social neuroscience, neuropsychology, psychoneuroimmunology, and sociogenomics. This book provides a scientific discourse on how...

Society within the Brain provides insightful accounts of scientific research linking social connection with brain and cognitive aging through state-of-the-art research. This involves comprehensive social network analysis, social neuroscience, neuropsychology, psychoneuroimmunology, and sociogenomics. This book provides a scientific discourse on how...

The Korean Social Life, Health, and Aging Project (KSHAP) was a multidisciplinary prospective study conducted in South Korea that measured various health biomarkers from blood, hair, and brain MRIs, and examined their associations with sociocentric (global) social network data of older adults in two entire villages (or Cohorts). Cohort K included p...

Background and aims Considering the growing number of gamers worldwide and increasing public concerns regarding the negative consequences of problematic gaming, the aim of the present systematic review was to provide a comprehensive overview of gaming disorder (GD) by identifying empirical studies that investigate biological, psychological, and soc...

Long-term exposure to particulate matter 2.5 (PM2.5) has been associated with impaired episodic memory function and an elevated risk of Alzheimer’s disease. We investigated the impact of PM2.5 on brain atrophy and explored whether the reduced brain volumes mediate the association between PM2.5 exposure and memory function in late life. Additionally...

Background: Social connections are crucial to human health and well-being. Previous research on molecular mechanisms in health has focused primarily on the individual-level perception of social connections (e.g., loneliness). This study adopted socio-centric social network analysis that includes all social ties from the entire population of interes...

Social exclusion occurs in various types of social relationships, from anonymous others to close friends. However, the role that social relationships play in social exclusion is less well known because most paradigms investigating social exclusion have been done in laboratory contexts, without considering the features of individuals' real-world soc...

Despite widespread public interest in problematic gaming interventions, questions regarding the empirical status of treatment efficacy persist. We conducted pairwise and network meta-analyses based on 17 psychological intervention studies on excessive gaming (n = 745 participants). The pairwise meta-analysis showed that psychological interventions...

Introduction We have demonstrated that intensive cognitive training can produce sustained improvements in cognitive performance in adolescents. Few studies, however, have investigated the neural basis of these training effects, leaving the underlying mechanism of cognitive plasticity during this period unexplained. Methods In this study, we traine...

This study aimed to examine legal regulations on psychologists worldwide, such as those related to professional status and training models. An online survey was conducted by members of the Global Psychology Alliance and Asia Pacific Psychology Alliance. The survey included information on the legal status of psychologists in 55 countries. Representa...

Verbal learning test can include a trial of interference process that intrude initial learning and impose additional cognitive stress. However, it has been unclear whether the multiple memory processes underly different brain structural bases. We measured performances of word retrieval that represents distinct memory processes (initial learning, in...

One in four Koreans reported at least one mental health problem in their lifetime, and the suicide rate has been at the highest level among the OECD member countries for about two decades. Happiness and Social Integration indexes show lowest level in recent years. In this study, we analyzed the OECD’s recommendations for Korea’s mental health syste...

Increasing evidence suggests a significant impact of higher psychological well‐being (PWB) on health outcomes; however, such associations have been studied exclusively in middle‐aged to older adults. This study examined the aging effect on PWB measures as well as the moderating effect of age on the link between PWB and inflammation, using salivary...

Trait impulsivity is known as a psychological construct that explains behavioral problems, including lack of attention, personality disorders, and substance use disorders in children and adolescents. While neurobiological mechanisms of adolescents' impulsivity measured with behavioral lab tasks have been revealed using functional brain imaging tech...

Background: An association between gaming disorder (GD) and the symptoms of common mental disorders is unraveled yet. In this preregistered study, we quantitatively synthesized reliability, convergent and discriminant validity of GD scales to examine association between GD and other constructs. Methods: Five representative GD instruments (GAS-7, AI...

Background: Retirement and loss of important social relationships, including spouse and friends, make older adults more vulnerable to social isolation. Therefore, social activity could be important for older adults in maintaining life satisfaction and everyday functioning. Although several studies found protective roles of social activity against c...

Background Depressive symptoms in older adults are known to be associated with memory dysfunction. Among those symptoms, agitation is a key symptom that differentiates late life depression from general depression and is suggested as a risk factor for developing dementia. However, little is known about the relationship between depressive symptoms, i...

Background and aims: Considering the growing number of gamers worldwide and increasing public concerns regarding the negative consequences of problematic gaming, the aim of the present systematic review was to provide a comprehensive overview of internet gaming disorder (IGD) by identifying all empirical studies on biological, psychological, and so...

Background Gaming disorder (GD) has been listed in the International Classification of Diseases (ICD) 11th Revision. Studies on GD prevalence have been highly heterogeneous, and there are significant gaps in prevalence estimates. Few studies have examined what methodological and demographic factors could explain this phenomenon. Therefore, this met...

Objective: Several instruments have been developed to identify gaming disorder (GD). Five instruments (GAS-7, AICA, IGDT-10, Lemmens IGD-9, and IGDS9-SF) were chosen based on recommendations by King et al. (2020) to conduct a meta-analysis. Reliability, convergent and divergent validation (i.e., associations between GD and psychological variables)...

Introduction: Social isolation is detrimental to late-life health outcomes. Although objective social isolation is a major source of perceived loneliness, how different layers of social disconnection systematically constitute the subjective experience of loneliness remains unclear. Methods: This study focused on older adults who participated in...

Neuropsychological test is an essential tool in assessing cognitive and functional changes associated with late-life neurocognitive disorders. Despite the utility of the neuropsychological test, the brain-wide neural basis of the test performance remains unclear. Using the predictive modeling approach, we aimed to identify the optimal combination o...

To avoid polarization and maintain small-worldness in society, people who act as attitudinal brokers are critical. These people maintain social ties with people who have dissimilar and even incompatible attitudes. Based on resting-state functional magnetic resonance imaging (n = 139) and the complete social networks from two Korean villages (n = 15...

Significance In what ways are we similar to our friends? Here, we characterized the social network of residents of a remote village, a subset of whom contributed personality and neuroimaging data. We demonstrate that similarity in individuals’ resting-state functional connectomes predicts individuals’ proximity in their real-world social network, e...

Adolescence is a unique period in which higher cognition develops to adult-level, while plasticity of neuron and behavior is at one of its peak. Notably, cognitive training studies for adolescents has been sparse and neural correlates of the training effects yet to be established. This study investigated the effects of multi-component training of c...

Increasing evidence suggests that systemic inflammation adversely affects social experiences and behaviors of older adults by changing the functional state of the brain. In this study, we investigated the relationships among systemic inflammation, functional network connectivity (FNC) of the whole brain, and social-network size using complete socia...

Background: Systemic inflammation is suggested to play a role in several neuropathological processes. However, the precise relation of inflammation and the functionality of the aging brain is still unclear. Cognitive control function is one of the heavily affected cognitive abilities in regards to normal aging and its neural correlates, including t...

Background: Late-life loneliness is one of the risk factors for Alzheimer's disease (AD). Although a few studies have shown that feeling lonely is associated with lower cognitive function and accelerated cognitive decline, the systematic neuropathological mechanism of its relationship remains unknown. Therefore this study aimed to examine whether c...

Background Educational attainment and verbal intelligence, which indirectly reflect an individual's cognitive reserve (CR), is suggested to buffer the effect of late‐life brain degradation on cognitive performance outcome. We aimed to explore how the relationship between whole grey matter volume (GMV) and episodic memory function is altered by CR p...

Late-life depression has been considered to be associated with memory deficits and hippocampal volume reduction. Considering that not all depression patients undergo the same amount of cognitive impairment or regional brain volume loss, moderating factors such as complex mental activity and social activity have been examined to assess whether these...

Existing evidence suggests social isolation provokes perceived loneliness in older adults, however; inconsistent results have been reported such as loneliness in the crowd. In this research, we aimed to identify a social network position that is associated with loneliness and classify lonely older adults from non-lonely using the complete social ne...

Late-life depression has been reported to be associated with memory deficits and hippocampal volume reduction. In consideration of the fact that not all depression patients go through the same amount of cognitive impairment or regional brain volume loss, moderating factors including complex mental activity and social activity have been examined in...

Socially integrated lifestyle has a protective effect in a wide range of late-life health outcome, especially in age-related cognitive decline. Although studies revealed that the size of individual’s social network is associated with less cognitive decline, the reported effects are not consistent and its evidence of brain pathology remains elusive....

While the aging process is a universal phenomenon, people perceive and experience one's aging considerably differently. Subjective age (SA), referring to how individuals experience themselves as younger or older than their actual age, has been highlighted as an important predictor of late-life health outcomes. However, it is unclear whether and how...

The social brain hypothesis proposes that large neocortex size evolved to support cognitively demanding social interactions. Accordingly, previous studies have observed that larger orbitofrontal and amygdala structures predict the size of an individual's social network. However, it remains uncertain how an individual's social connectedness reported...

Objective The cognitive reserve theory explicates individual differences observed in the clinical manifestation of dementia despite similar brain pathology. Education, a popular proxy of the cognitive reserve, has been shown to have protective effects delaying the onset of clinical symptoms including memory. This study was conducted to test whether...

According to the cognitive reserve hypothesis, more educated older adults are less susceptible to age-related or pathological cognitive changes due to accumulated resources necessary for various cognitive tasks. Although previous studies have validated the concept of cognitive reserve, it remains elusive how the early experience of education alters...

Previous studies found that stress shifts behavioral control by promoting habits while decreasing goal-directed behaviors during reward-based decision-making. It is, however, unclear how stress disrupts the relative contribution of the two systems controlling reward-seeking behavior, i.e. model-free (or habit) and model-based (or goal-directed). He...

Task performance for each subject. (XLSX)

Social networks are known to protect cognitive function in old age. For the first time, this study examines how social network size and social network embeddedness measured by k-core score are associated with functional connectivity in the brain using the complete social network of an entire village. According to the results, social network size ha...

The aim of this study was to investigate the changes in cognitive functions and brain activation after multicomponent training of cognitive control in non-demented older adults, utilizing neuropsychological tests and fMRI. We developed and implemented a computerized Multicomponent Training of Cognitive Control (MTCC), characterized by task variabil...

People sharing similar characteristics are likely to be connected in social networks. The purpose of this study is to theoretically integrate homophily in social networks with neuroscience so that we can better understand complex human nature. In this study, homophily of older adults based on the amygdala volume was tested. Korean Social Health and...

Background and Purpose Vocabulary knowledge is used as a representative index of general intelligence, and is regarded as a marker for cognitive reserve in elderly people. However, vocabulary knowledge mainly depends on formal education, hence, it may not fully represent cognitive functioning in elderly people with poor educational backgrounds. Her...

Cognitive decline in dementia does not correspond precisely to the amount of neurodegeneration in the brain. This discrepancy in brain damage and its clinical manifestation has been explicated by the concept of reserve. Brain reserve inferred from the brain size had moderate success in explaining the discrepancy, and numerous studies have reported...

Objective: Clinical neuropsychology in South Korea, albeit its relatively short history, has advanced dramatically. We review a brief history and current status of clinical neuropsychology in South Korea. Method: The history, the educational pathway, the training pathway, the certification process, and careers in clinical neuropsychology in South K...

The accurate estimation of premorbid intellectual functioning in patients with known or suspected cognitive impairment is crucial for clinicians. However, there is no reliable method for estimating premorbid intelligence in South Korea. The purpose of this study was to develop the Korea Premorbid Intelligence Estimate (KPIE) as an estimate of the p...

In Asia, where illiteracy rates are high, determining the degree to which neuropsychological measures can be used to identify cognitive impairment in illiterate elders is important. The aim of this study was to evaluate the effectiveness of using formal neuropsychological assessments to distinguish healthy illiterate elders from dementia patients....