A Prospective Sociocentric Study of 2 Entire Traditional Korean Villages: The Korean Social Life, Health, and Aging Project (KSHAP).

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 magnetic resonance imaging, and we examined their associations with sociocentric (global) social network data of older adults in 2 entire villages (or cohorts). Cohort K included participants aged 60 years or older, and cohort L included participants aged 65 years or older. We performed a baseline survey involving 814 of the 860 individuals (94.7% response rate) in cohort K in 2012 and 947 of the 1,043 individuals (90.8% response rate) in cohort L in 2017. We gathered longitudinal data for 5 waves in cohort K from 2011 to 2019 and 2 waves in cohort L from 2017 to 2022. Here, we describe for the first time the follow-up design of the KSHAP, the changes in social networks, and various biomarkers over a number of years. The data for cohort K are publicly available via the Korean Social Science Data Archive as well as the project website, and the data for cohort L will be shared soon.

Similarity in functional brain connectivity at rest predicts interpersonal closeness in the social network of an entire village.

People often have the intuition that they are similar to their friends, yet evidence for homophily (being friends with similar others) based on self-reported personality is inconsistent. Functional connectomes-patterns of spontaneous synchronization across the brain-are stable within individuals and predict how people tend to think and behave. Thus, they may capture interindividual variability in latent traits that are particularly similar among friends but that might elude self-report. Here, we examined interpersonal similarity in functional connectivity at rest-that is, in the absence of external stimuli-and tested if functional connectome similarity is associated with proximity in a real-world social network. The social network of a remote village was reconstructed; a subset of residents underwent functional magnetic resonance imaging. Similarity in functional connectomes was positively related to social network proximity, particularly in the default mode network. Controlling for similarities in demographic and personality data (the Big Five personality traits) yielded similar results. Thus, functional connectomes may capture latent interpersonal similarities between friends that are not fully captured by commonly used demographic or personality measures. The localization of these results suggests how friends may be particularly similar to one another. Additionally, geographic proximity moderated the relationship between neural similarity and social network proximity, suggesting that such associations are particularly strong among people who live particularly close to one another. These findings suggest that social connectivity is reflected in signatures of brain functional connectivity, consistent with the common intuition that friends share similarities that go beyond, for example, demographic similarities.

Social Network Characteristics Predict Loneliness in Older Adults.

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 the Korean Social Life, Health, and Aging Project (KSHAP) (n = 1,724; mean age = 72.91 years) and examined how the proximal and distal characteristics of social networks predict loneliness using a hierarchical linear regression model. The study also investigated whether the major loss of social roles (marital and working status) influences perceived loneliness through the proximal and distal aspects of social networks by cross-sectional mediation analysis. RESULTS: This study found that the proximal (subjective number of connections) and distal (brokerage and embeddedness) aspects of social networks additively explained the frequency of loneliness. Moreover, the loss of late-life social roles (marital and working status) was related to an increase in loneliness, where the distal characteristic of social networks mediated this relationship. DISCUSSION/CONCLUSION: The results of this study suggest that the proximal and the distal characteristic of social networks is a social determinant predicting loneliness in late life. Besides, the loss of bridging and cohesive position among community networks may be a critical pathway to psychosocial transition after marital and working status changes.

Distributed functional connectivity predicts neuropsychological test performance among older adults.

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 of functional connectivities that predicts neuropsychological test scores of novel individuals. Resting-state functional connectivity and neuropsychological tests included in the OASIS-3 dataset (n = 428) were used to train the predictive models, and the identified models were iteratively applied to the holdout internal test set (n = 216) and external test set (KSHAP, n = 151). We found that the connectivity-based predicted score tracked the actual behavioral test scores (r = 0.08-0.44). The predictive models utilizing most of the connectivity features showed better accuracy than those composed of focal connectivity features, suggesting that its neural basis is largely distributed across multiple brain systems. The discriminant and clinical validity of the predictive models were further assessed. Our results suggest that late-life neuropsychological test performance can be formally characterized with distributed connectome-based predictive models, and further translational evidence is needed when developing theoretically valid and clinically incremental predictive models.

Neural and social correlates of attitudinal brokerage: using the complete social networks of two entire villages.

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 = 1508), we investigated the individual-level neural capacity and social-level structural opportunity for attitudinal brokerage regarding gender role attitudes. First, using a connectome-based predictive model, we successfully identified the brain functional connectivity that predicts attitudinal diversity of respondents' social network members. Brain regions that contributed most to the prediction included mentalizing regions known to be recruited in reading and understanding others' belief states. This result was corroborated by leave-one-out cross-validation, fivefold cross-validation and external validation where the brain connectivity identified in one village was used to predict the attitudinal diversity in another independent village. Second, the association between functional connectivity and attitudinal diversity of social network members was contingent on a specific position in a social network, namely, the structural brokerage position where people have ties with two people who are not otherwise connected.

Moderating effect of cognitive reserve on the association between grey matter atrophy and memory varies with age in older adults.

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 proxy as well as age in healthy older adults. METHODS: Elderly Verbal Learning Test (EVLT) and structural magnetic resonance imaging were administered to 110 community-residing older adults. Moderated moderation model tested whether the association between whole GMV and episodic memory was moderated by both CR and chronological age. RESULTS: The results showed that the moderating effect of CR on Immediate Recall, Short-delay Recall, and Recognition scores of EVLT differed across age groups. The elderly with higher CR showed steeper GMV effect on EVLT at the Age-Younger condition, while such moderating effect was reversed in the Age-Older condition, suggesting an alleviated brain atrophy effect in higher CR elderly. CONCLUSION: These findings suggest that although higher CR elderly may exhibit earlier GMV-related memory decline, the buffering effect of CR on the cognitive decline due to brain atrophy would become more evident in old-old elderly people who are likely to have accumulated more neuropathological changes. This study underscores chronological age as an important moderating factor in examining the moderating role of CR in late-life memory function.

Associations of systemic inflammation with frontotemporal functional network connectivity and out-degree social-network size in community-dwelling older adults.

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 social-network data of older adults residing in a Korean village. Sixty-one participants were recruited from the Korean Social Life, Health, and Aging Project (KSHAP). Participants underwent a resting-state functional magnetic resonance imaging scan. High sensitivity C-reactive protein (hs-CRP) levels were measured as an inflammation marker. In-degree and out-degree network sizes were calculated based on the total number of intimate social relationships per participant. We demonstrated that hs-CRP levels were associated with decreased frontotemporal FNC. Stronger frontotemporal FNC was significantly correlated with a larger out-degree network size, suggesting that impaired frontotemporal communication in older adults decreases perceived social connectedness with other people. An exploratory mediation analysis supported the observation that increased systemic inflammation contributes to reduced out-degree social-network size among older adults by changing frontotemporal FNC. The present findings provide meaningful insight into the complex relationship between systemic inflammation and social quality of life.

Social brain volume is associated with in-degree social network size among older adults.

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 by other people is associated with the social brain volume. In this study, we found that a greater in-degree network size, a measure of social ties identified by a subject's social connections rather than by the subject, significantly correlated with a larger regional volume of the orbitofrontal cortex, dorsomedial prefrontal cortex and lingual gyrus. By contrast, out-degree size, which is based on an individual's self-perceived connectedness, showed no associations. Meta-analytic reverse inference further revealed that regional volume pattern of in-degree size was specifically involved in social inference ability. These findings were possible because our dataset contained the social networks of an entire village, i.e. a global network. The results suggest that the in-degree aspect of social network size not only confirms the previously reported brain correlates of the social network but also shows an association in brain regions involved in the ability to infer other people's minds. This study provides insight into understanding how the social brain is uniquely associated with sociocentric measures derived from a global network.

Association between Loneliness and Memory Function through White Matter Hyperintensities in Older Adults: The Moderating Role of Gender.

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 underlying the association between loneliness and episodic memory function and explore whether it varies with gender among cognitively normal older adults. A total of 173 community-dwelling adults aged 60 years or older from the Korean Social Life, Health, and Aging Project (KSHAP) study (mean age = 71.87) underwent an assessment of loneliness, neuropsychological testing, and structural magnetic resonance imaging. The association between loneliness and episodic memory function was mediated by the volume of white matter hyperintensities (WMHs), but not by hippocampal or gray matter volumes. In addition, the association between loneliness and memory function through WMHs was significantly moderated by gender; specifically, the indirect effect was significant among men but not among women. The study suggests that WMHs may be a potential neurological mechanism that causes late-life memory dysfunction associated with loneliness in older men. The findings underscore the need for gender-specific interventions to mitigate memory impairment associated with late-life loneliness, with significant public health implications.

Social network position and the Conserved Transcriptional Response to Adversity in older Koreans.

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 interest to examine the group-level social connections and their association with a molecular genomic measure of health. METHODS: Using socio-centric (global) social network data from an entire village in Korea, we investigated how social network characteristics are related to immune cell gene expression among older adults. Blood samples were collected (N = 53, 65-79 years) and mixed effect linear model analyses were performed to examine the association between social network characteristics and Conserved Transcriptional Response to Adversity (CTRA) RNA expression patterns. RESULTS: Social network positions measured by k-core score, the degree of cohesive core positions in an entire village, were significantly associated with CTRA downregulation. Such associations emerged above and beyond the effects of perceived social isolation (loneliness) and biobehavioral risk factors (smoking, alcohol, BMI, etc.). Social network size, defined as degree centrality, was also associated with reduced CTRA gene expression, but its association mimicked that of perceived social isolation (loneliness). CONCLUSIONS: The current findings implicate community-level social network characteristics in the regulation of individual human genome function above and beyond individual-level perceptions of connectedness.

Brain connectivity during social exclusion differs depending on the closeness within a triad among older adults living in a village.

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 social relationships. Here, we addressed this gap by examining how pre-existing social relationships with rejecters may influence the brain response of individuals experiencing social exclusion. Eighty-eight older adults living in a rural village visited the laboratory with two other participants living in the same village and played Cyberball in an Magnetic Resonance Imaging scanner. Utilizing whole-brain connectome-based predictive modeling, we analyzed functional connectivity (FC) data obtained during the social exclusion task. First, we found that the level of self-reported distress during social exclusion was significantly related to sparsity, i.e. lack of closeness, within a triad. Furthermore, the sparsity was significantly predicted by the FC model, demonstrating that a sparse triadic relationship was associated with stronger connectivity patterns in brain regions previously implicated in social pain and mentalizing during Cyberball. These findings extend our understanding of how real-world social intimacy and relationships with excluders affect neural and emotional responses to social exclusion.

Biopsychosocial factors of gaming disorder: a systematic review employing screening tools with well-defined psychometric properties.

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 social factors of GD using screening tools with well-defined psychometric properties. Materials and methods: A systematic literature search was conducted through PsycINFO, PubMed, RISS, and KISS, and papers published up to January 2022 were included. Studies were screened based on the GD diagnostic tool usage, and only five scales with well-established psychometric properties were included. A total of 93 studies were included in the synthesis, and the results were classified into three groups based on biological, psychological, and social factors. Results: Biological factors (n = 8) included reward, self-concept, brain structure, and functional connectivity. Psychological factors (n = 67) included psychiatric symptoms, psychological health, emotion regulation, personality traits, and other dimensions. Social factors (n = 29) included family, social interaction, culture, school, and social support. Discussion: When the excess amount of assessment tools with varying psychometric properties were controlled for, mixed results were observed with regards to impulsivity, social relations, and family-related factors, and some domains suffered from a lack of study results to confirm any relevant patterns. Conclusion: More longitudinal and neurobiological studies, consensus on a diagnostic tool with well-defined psychometric properties, and an in-depth understanding of gaming-related factors should be established to settle the debate regarding psychometric weaknesses of the current diagnostic system and for GD to gain greater legitimacy in the field of behavioral addiction.

Psychological well-being and salivary markers of inflammation: The moderating effect of age.

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 markers by comparing the younger adults (n = 127; Mage = 22.98 years) versus older adults (n = 75; Mage = 75.60 years). Older adults showed significantly lower levels of PWB, particularly regarding purpose in life and personal growth. Moreover, higher purpose in life was associated with lower salivary IL-1ß and IL-6 (b = 0.83, p < .001; b = 0.81, p < .01) only in the older adult group but not in younger adults. These findings highlight the potential buffering effect of the sense of living well on physiological pathways in later life.

Distinct neuroanatomical correlates of interference-related verbal episodic memory test in healthy older adults.

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, interference, and retention) and regional gray matter morphology from 230 cognitively unimpaired older adults. We identified three distinct multivariate pattern modes using canonical correlation analysis that map correspondence between memory and brain morphometry. The first mode comprised weights highly loaded on temporal lobe and overall performances. The second mode reflected subcortical volumes and initial learning performances. The third mode comprised thickness in the lateral prefrontal and parietal cortex and captured an ability to resist retroactive interference effect. While overall test performance reflected the temporal lobe and whole-gray matter volume, the interim trial of interference signifies neural correlates extending to subcortical and frontoparietal regions.

Cognitive control training enhances the integration of intrinsic functional networks in adolescents.

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 trained 51 typically developing adolescents on cognitive control tasks and examined how their intrinsic brain networks changed by applying graph theoretical analysis. We hypothesized that the training would accelerate the process of network integration, which is a key feature of network development throughout adolescence. Results: We found that the cognitive control training enhanced the integration of functional networks, particularly the cross-network integration of the cingulo-opercular network. Moreover, the analysis of additional data from older adolescents revealed that the cingulo-opercular network was more integrated with other networks in older adolescents than in young adolescents. Discussion: These findings are consistent with the hypothesis that cognitive control training may speed up network development, such that brain networks exhibit more mature patterns after training.

Prevalence of gaming disorder: A meta-analysis.

BACKGROUND: Gaming disorder (GD) has been listed in the International Classification of Diseases 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 meta-analytic study quantifies globally reported GD prevalence rates and explores their various moderating variables. METHODS: Prevalence estimates were extracted from 61 studies conducted before December 3, 2020, which included 227,665 participants across 29 countries. Subgroup and moderator analyses were used to investigate the potential causes of heterogeneity, including region, sample size, year of data collection, age group, study design, sampling method, survey format, sample type, risk of bias, terminology, assessment tool, and male proportion. RESULTS: The overall pooled prevalence of GD was 3.3% (95% confidence interval: 2.6-4.0) (8.5% in males and 3.5% in females). By selecting only 28 representative sample studies, the prevalence estimate was reduced to 2.4% (95% CI 1.7-3.2), and the adjusted prevalence estimate using the trim-and-fill method was 1.4% (95% CI 0.9-1.9). High heterogeneity in GD prevalence rates was influenced by various moderators, such as participant variables (e.g., region, sample size, and age) and study methodology (e.g., study design, sampling method, sample type, terminology, and instrument). The moderator analyses revealed that the sample size, mean age, and study quality were negatively associated with GD prevalence. CONCLUSIONS: This study confirms that GD prevalence studies were highly heterogeneous based on participant demographics and research methodologies. Various confounding variables, such as sampling methods, sample types, assessment tools, age, region, and cultural factors have significantly influenced the GD prevalence rates. Prevalence estimates are likely to vary depending on study quality. Further epidemiological studies should be conducted using rigorous methodological standards to more accurately estimate GD prevalence.

Psychological treatments for excessive gaming: a systematic review and meta-analysis.

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 reduce excessive gaming more than the inactive control (standardized mean difference [SMD] = 1.70, 95% confidence interval [CI] 1.27 to 2.12) and active control (SMD = 0.88, 95% CI 0.21 to 1.56). The network meta-analysis showed that a combined treatment of Cognitive Behavioral Therapy (CBT) and Mindfulness was the most effective intervention in reducing excessive gaming, followed by a combined CBT and Family intervention, Mindfulness, and then CBT as a standalone treatment. Due to the limited number of included studies and resulting identified methodological concerns, the current results should be interpreted as preliminary to help support future research focused on excessive gaming interventions. Recommendations for improving the methodological rigor are also discussed.

Differentiating illiteracy from Alzheimer's disease by using neuropsychological assessments.

BACKGROUND: 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. METHODS: We compared the cognitive performance of healthy elders who were illiterate (illiterate NC, n = 25) with those who were literate (literate NC, n = 25), literate patients with mild Alzheimer's disease (literate AD, n = 25), and illiterate patients with mild AD (illiterate AD, n = 25). Neuropsychological measures included the Mini-Mental State Examination (MMSE), the verbal fluency test, the Boston naming test, the Rosen drawing test, and the verbal learning test. RESULTS: In the between-group analyses, the scores on all tests, except verbal fluency and recognition memory, were lower for illiterate NC compared to the literate NC. The scores on the MMSE, Boston naming test, Rosen drawing test, and immediate free recall could not distinguish the illiterate NC from literate AD. However, the scores on all tests, except the Rosen drawing test, could distinguish illiterate NC from illiterate AD. ROC analyses showed the same pattern of results. In addition, age-, sex-, and education-matched cut-off scores of all tests, except immediate recall and delayed recall trials of the verbal learning test, showed good specificities in participants who were illiterate compared to those in participants who were literate. CONCLUSION: These findings suggest that the impact of literacy on neuropsychological test performance is an important aspect of cognitive evaluations for elders who are illiterate.

Reliability, and Convergent and Discriminant Validity of Gaming Disorder Scales: A Meta-Analysis.

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, AICA, IGDT-10, Lemmens IGD-9, and IGDS9-SF) were chosen based on recommendations by the previous systematic review study to conduct correlation meta-analyses and reliability generalization. A systematic literature search was conducted through Pubmed, Proquest, Embase, and Google Scholar to identify studies that reported information on either reliability or correlation with related variables. 2,124 studies were full-text assessed as of October 2020, and 184 were quantitatively synthesized. Conventional Hedges two-level meta-analytic method was utilized. Results: The result of reliability generalization reported a mean coefficient alpha of 0.86 (95% CI = 0.85-0.87) and a mean test-retest estimate of 0.86 (95% CI = 0.81-0.89). Estimated effect sizes of correlation between GD and the variables were as follows: 0.33 with depression (k = 45; number of effect sizes), 0.29 with anxiety (k = 37), 0.30 with aggression (k = 19), -0.22 with quality of life (k = 18), 0.29 with loneliness (k = 18), 0.56 with internet addiction (k = 20), and 0.40 with game playtime (k = 53), respectively. The result of moderator analyses, funnel and forest plots, and publication bias analyses were also presented. Discussion and Conclusion: All five GD instruments have good internal consistency and test-retest reliability. Relatively few studies reported the test-retest reliability. The result of correlation meta-analysis revealed that GD scores were only moderately associated with game playtime. Common psychological problems such as depression and anxiety were found to have a slightly smaller association with GD than the gaming behavior. GD scores were strongly correlated with internet addiction. Further studies should adopt a rigorous methodological procedure to unravel the bidirectional relationship between GD and other psychopathologies. Limitations: The current study did not include gray literature. The representativeness of the five tools included in the current study could be questioned. High heterogeneity is another limitation of the study. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42020219781].

Effects of education, literacy, and dementia on the Clock Drawing Test performance.

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, including education, and established norms for the elderly population. We found that the educational attainment and literacy status of older people influenced performance on the CDT significantly (p < .001). Furthermore, qualitative error analysis revealed that normal participants with low educational background committed errors similar to errors of the DAT patients. The DAT patients performed significantly worse than the non-demented participants in the CDT Total score (p < .001). However, the CDT has better criterion validity in participants with more than 6 years of education. In conclusion, the CDT performance in older people who are either illiterate or with 6 or less years of education should be interpreted with caution. Conceptual errors in the CDT can be the result of not only dementia but also lack of education.