Different neural pathways linking personality traits and eudaimonic well-being: a resting-state functional magnetic resonance imaging study

Striatal-hippocampal functional connectivity contributes to real-life positive anticipatory experiences and subjective well-being

Positive anticipatory experiences are key to daily well-being. However, the brain's functional architecture underlying real-world positive anticipatory experiences and well-being remains unexplored. In the present study, we combined an ecological momentary assessment and resting-state functional neuroimaging to identify the neural predictors of real-world positive anticipatory experiences and explore their relationships with subjective well-being (SWB). With a model-based approach, we quantified participants' accuracy in predicting positive events and the degree to which participants' affective states were influenced by the positive anticipation. We found that individuals with higher accuracy in predicting upcoming positive events showed greater SWB, and this relationship was mediated by greater positive anticipatory feelings. Importantly, functional connectivity of the dorsal and ventral striatal-hippocampal networks significantly predicted the accuracy and positive anticipatory feelings, respectively. These functional networks were further predictive of SWB. Our findings provide novel and ecologically valid evidence that the interaction between neural systems for reward-processing and memory plays an important role in real-life positive anticipatory experiences and everyday SWB.

Understanding Wellbeing Profiles According to White Matter Structural Connectivity Sub-types in Early Adolescents: The First Hundred Brains Cohort from the Longitudinal Adolescent Brain Study

Wellbeing is protective against the emergence of psychopathology. Neurobiological markers associated with mental wellbeing during adolescence are important to understand. Limited research has examined neural networks (white matter tracts) and mental wellbeing in early adolescence specifically. A cross-sectional diffusion tensor imaging analysis approach was conducted, from the Longitudinal Adolescent Brain study, First Hundred Brains cohort (N = 99; 46.5% female; Mage = 13.01, SD = 0.55). Participants completed self-report measures including wellbeing, quality-of-life, and psychological distress. Potential neurobiological profiles using fractional anisotropy, axial, and radial diffusivity were determined via a whole brain voxel-wise approach, and hierarchical cluster analysis of fractional anisotropy values, obtained from 21 major white matter tracts. Three cluster groups with significantly different neurobiological profiles were distinguished. No significant differences were found between the three cluster groups and measures of wellbeing, but two left lateralized significant associations between white matter tracts and wellbeing measures were found. These results provide preliminary evidence for potential neurobiological markers of mental health and wellbeing in early adolescence and should be tracked longitudinally to provide more detailed and robust findings.

The neurofunctional basis of human aggression varies by levels of femininity

Aggression can be categorized into reactive aggression (RA) and proactive aggression (PA) based on their underlying motivations. However, previous research has rarely identified the relationship between femininity and RA/PA, and there is a lack of understanding regarding the femininity-related neurofunctional basis of these aggressive behaviors. Thus, this study first examined the relationships between femininity and aggression, then explored the aggression-by-femininity interactions on the fractional amplitude of low-frequency fluctuations using resting-state fMRI among 705 university participants (mean age = 19.14 ± 0.99). The behavioral data indicated that femininity was more negatively associated with RA and PA when masculinity was controlled for. Additionally, the neural data revealed that femininity-specific relationships of RA in the left middle occipital gyrus (i.e. individuals with low femininity had positive relationships between RA and the left middle occipital gyrus, whereas those with high femininity had negative relationships) as well as of PA in the left middle frontal gyrus (i.e. individuals with high femininity showed significant negative relationships, whereas those with low femininity did not exhibit significant relationships). These findings reflect that individuals with varying levels of femininity exhibit distinct neural bases when expressing different subtypes of aggression, which are associated with societal expectations of gender.

The neural correlates of perceived social support and its relationship to psychological well-being

Introduction

Perceived social support is considered to play a significant role in promoting individuals' health and well-being, and yet the neural correlates of perceived social support were not fully understood. An exploration of the neural correlates of individual differences in the SPS can help us to gain more comprehensive understanding about the neural correlates of perceived social support. What's more, our study will explore the relationship among perceived social support, brain regions, and psychological well-being, which may provide new insights into the neural correlates underlying the relationship between perceived social support and psychological well-being from the perspective of cognitive neuroscience.

Methods

Herein, we used the Social Provisions Scale to assess individuals' perceived social support, and magnetic resonance imaging was used to measure the gray matter (GM) volume of the whole brain. What's more, we also measured psychological well-being using the Psychological Well-Being Scale, and mediation analysis was used to explore the relationship among perceived social support, brain regions, and psychological well-being.

Results

The voxel-based morphometry analysis of the whole brain revealed that perceived social support was positively correlated with GM volume of the left middle temporal gyrus (MTG). The finding indicated that a person with greater GM volume in the left MTG perceived more social support. More importantly, the left MTG GM volume observed above was also associated with psychological well-being, and the link between the two was mediated by perceived social support.

Discussion

These results revealed the importance of MTG for perceived social support and psychological well-being, and also suggested that perceived social support might explain the relationship between MTG and psychological well-being.

Brain imaging studies of emotional well-being: a scoping review

This scoping review provides an overview of previous empirical studies that used brain imaging techniques to investigate the neural correlates of emotional well-being (EWB). We compiled evidence on this topic into one accessible and usable document as a foundation for future research into the relationship between EWB and the brain. PRISMA 2020 guidelines were followed. We located relevant articles by searching five electronic databases with 95 studies meeting our inclusion criteria. We explored EWB measures, brain imaging modalities, research designs, populations studied, and approaches that are currently in use to characterize and understand EWB across the literature. Of the key concepts related to EWB, the vast majority of studies investigated positive affect and life satisfaction, followed by sense of meaning, goal pursuit, and quality of life. The majority of studies used functional MRI, followed by EEG and event-related potential-based EEG to study the neural basis of EWB (predominantly experienced affect, affective perception, reward, and emotion regulation). It is notable that positive affect and life satisfaction have been studied significantly more often than the other three aspects of EWB (i.e., sense of meaning, goal pursuit, and quality of life). Our findings suggest that future studies should investigate EWB in more diverse samples, especially in children, individuals with clinical disorders, and individuals from various geographic locations. Future directions and theoretical implications are discussed, including the need for more longitudinal studies with ecologically valid measures that incorporate multi-level approaches allowing researchers to better investigate and evaluate the relationships among behavioral, environmental, and neural factors.

Systematic review registration

https://osf.io/t9cf6/.

Associations between mental wellbeing and fMRI neural bases underlying responses to positive emotion in a twin sample

BACKGROUND

Although mental wellbeing has been linked with positive health outcomes, including longevity and improved emotional and cognitive functioning, studies examining the underlying neural mechanisms of both subjective and psychological wellbeing have been sparse. We assessed whether both forms of wellbeing are associated with neural activity engaged during positive and negative emotion processing and the extent to which this association is driven by genetics or environment.

METHODS

We assessed mental wellbeing in 230 healthy adult monozygotic and dizygotic twins using a previously validated questionnaire (COMPAS-W) and undertook functional magnetic resonance imaging during a facial emotion viewing task. We used linear mixed models to analyse the association between COMPAS-W scores and emotion-elicited neural activation. Univariate twin modelling was used to evaluate heritability of each brain region. Multivariate twin modelling was used to compare twin pairs to assess the contributions of genetic and environmental factors to this association.

RESULTS

Higher levels of wellbeing were associated with greater neural activity in the dorsolateral prefrontal cortex, localised in the right inferior frontal gyrus (IFG), in response to positive emotional expressions of happiness. Univariate twin modelling showed activity in the IFG to have 20% heritability. Multivariate twin modelling suggested that the association between wellbeing and positive emotion-elicited neural activity was driven by common variance from unique environment (r = 0.208) rather than shared genetics.

CONCLUSIONS

Higher mental wellbeing may have a basis in greater engagement of prefrontal neural regions in response to positive emotion, and this association may be modifiable by unique life experiences.

A systematic review of the neural correlates of well-being reveals no consistent associations

Findings from behavioral and genetic studies indicate a potential role for the involvement of brain structures and brain functioning in well-being. We performed a systematic review on the association between brain structures or brain functioning and well-being, including 56 studies. The 11 electroencephalography (EEG) studies suggest a larger alpha asymmetry (more left than right brain activation) to be related to higher well-being. The 18 Magnetic Resonance Imaging (MRI) studies, 26 resting-state functional MRI studies and two functional near-infrared spectroscopy (fNIRS) studies identified a wide range of brain regions involved in well-being, but replication across studies was scarce, both in direction and strength of the associations. The inconsistency could result from small sample sizes of most studies and a possible wide-spread network of brain regions with small effects involved in well-being. Future directions include well-powered brain-wide association studies and innovative methods to more reliably measure brain activity in daily life.

Functional connectivity of the central autonomic and default mode networks represent neural correlates and predictors of individual personality

There is solid evidence for the prominent involvement of the central autonomic and default mode systems in shaping personality. However, whether functional connectivity of these systems can represent neural correlates and predictors of individual variation in personality traits is largely unknown. Resting-state functional magnetic resonance imaging data of 215 healthy young adults were used to construct the sympathetic (SN), parasympathetic (PN), and default mode (DMN) networks, with intra- and internetwork functional connectivity measured. Personality factors were assessed using the five-factor model. We examined the associations between personality factors and functional network connectivity, followed by performance of personality prediction based on functional connectivity using connectome-based predictive modeling (CPM), a recently developed machine learning approach. All personality factors (neuroticism, extraversion, conscientiousness, and agreeableness) other than openness were significantly correlated with intra- and internetwork functional connectivity of the SN, PN, and DMN. Moreover, the CPM models successfully predicted conscientiousness and agreeableness at the individual level using functional network connectivity. Our findings may expand existing knowledge regarding the neural substrates underlying personality.

Brain Structural Correlates of Dispositional Insight and the Mediation Role of Neuroticism in Young Adults

Studies on the neural correlates of episodic insight have made significant progress in the past decades. However, the neural mechanisms underlying dispositional insight are largely unknown. In the present study, we recruited forty-four young, healthy adults and performed several analyses to reveal the neural mechanisms of dispositional insight. Firstly, a voxel-based morphometry (VBM) technique was used to explore the structural brain mechanisms of dispositional insight. We found that dispositional insight was significantly and negatively correlated with the regional gray matter volume (rGMV) in the left thalamus (TLM.L), right temporoparietal junction (TPJ.R), and left dorsal medial prefrontal cortex (DMPFC.L). Secondly, we performed a seed-based resting-state functional connectivity (RSFC) analysis to complement the findings of VBM analysis further. The brain regions of TLM.L, DMPFC.L, and TPJ.R were selected as seed regions. We found that dispositional insight was associated with altered RSFC between the DMPFC.L and bilateral TPJ, between the TPJ.R and left dorsolateral prefrontal cortex, left ventrolateral prefrontal cortex, DMPFC.L, TPJ.L, right insula, and right cerebellum. Finally, a mediation analysis found that the personality of neuroticism partially mediated the relationship between the brain region of TLM.L and dispositional insight. These findings imply that dispositional insight has a specific functional and structural neural mechanism. The personality of neuroticism may play a pivotal role in the processes of dispositional insight.

Well-Being Is Associated With Local to Remote Cortical Connectivity

Wellbeing refers to cognitive and emotional appraisal of an individual’s life and social functioning, which is of great significance to the quality of life of an individual and society. Previous studies have revealed the neural basis of wellbeing, which mostly focused on human brain morphology or network-level connectivity. However, local-to-remote cortical connectivity, which plays a crucial role in defining the human brain architecture, has not been investigated in wellbeing. To examine whether wellbeing was associated with local-to-remote cortical connectivity, we acquired resting-state images from 60 healthy participants and employed the Mental Health Continuum Short Form to measure wellbeing, including three dimensions, namely, emotional wellbeing, psychological wellbeing, and social wellbeing. Functional homogeneity (ReHo) and seed-based functional connectivity were used to evaluate local-to-remote cortical connectivity in these participants. For local connectivity, our results showed that ReHo in the right orbitofrontal sulcus was significantly positively correlated with psychological wellbeing but negatively correlated with social wellbeing. For remote connectivity, connectivity within the right orbitofrontal cortex and interhemispheric connectivity of the orbitofrontal sulcus were both positively associated with psychological wellbeing; functional connectivity between the right orbitofrontal sulcus and the left postcentral sulcus was positively associated with social wellbeing. Our results showed that wellbeing was indeed associated with local-to-remote cortical connectivity, and our findings supplied a new perspective of distance-related neural mechanisms of wellbeing.

Frontoinsular cortical microstructure is linked to life satisfaction in young adulthood

Life satisfaction is a component of subjective well-being that reflects a global judgement of the quality of life according to an individual's own needs and expectations. As a psychological construct, it has attracted attention due to its relationship to mental health, resilience to stress, and other factors. Neuroimaging studies have identified neurobiological correlates of life satisfaction; however, they are limited to functional connectivity and gray matter morphometry. We explored features of gray matter microstructure obtained through compartmental modeling of multi-shell diffusion MRI data, and we examined cortical microstructure in frontoinsular cortex in a cohort of 807 typical young adults scanned as part of the Human Connectome Project. Our experiments identified the orientation dispersion index (ODI), and analogously fractional anisotropy (FA), of frontoinsular cortex as a robust set of anatomically-specific lateralized diffusion MRI microstructure features that are linked to life satisfaction, independent of other demographic, socioeconomic, and behavioral factors. We further validated our findings in a secondary test-retest dataset and found high reliability of our imaging metrics and reproducibility of outcomes. In our analysis of twin and non-twin siblings, we found basic microstructure in frontoinsular cortex to be strongly genetically determined. We also found a more moderate but still very significant genetic role in determining microstructure as it relates to life satisfaction in frontoinsular cortex. Our findings suggest a potential linkage between well-being and microscopic features of frontoinsular cortex, which may reflect cellular morphology and architecture and may more broadly implicate the integrity of the homeostatic processing performed by frontoinsular cortex as an important component of an individual's judgements of life satisfaction.

Intrinsic functional network contributions to the relationship between trait empathy and subjective happiness

Subjective happiness (well-being) is a multi-dimensional construct indexing one's evaluations of everyday emotional experiences and life satisfaction, and has been associated with different aspects of trait empathy. Despite previous research identifying the neural substrates of subjective happiness and empathy, the mechanisms mediating the relationship between the two constructs remain largely unclear. Here, we performed a data-driven, multi-voxel pattern analysis of whole-brain intrinsic functional connectivity to reveal the neural mechanisms of subjective happiness and trait empathy in a sample of young females. Behaviorally, we found that subjective happiness was negatively associated with personal distress (i.e., self-referential experience of others' feelings). Consistent with this inverse relationship, subjective happiness was associated with the dorsolateral prefrontal cortex exhibiting decreased functional connectivity with regions important for the representation of unimodal sensorimotor information (e.g., primary sensory cortices) or multi-modal summaries of brain states (e.g., default mode network) and increased functional connectivity with regions important for the attentional modulation of these representations (e.g., frontoparietal, attention networks). Personal distress was associated with the medial prefrontal cortex exhibiting functional connectivity differences with similar networks--but in the opposite direction. Finally, intrinsic functional connectivity within and between these networks fully mediated the relationship between the two behavioral measures. These results identify an important contribution of the macroscale functional organization of the brain to human well-being, by demonstrating that lower levels of personal distress lead to higher subjective happiness through variation in intrinsic functional connectivity along a neural representation vs. modulation gradient.

Polygenic Score of Subjective Well-Being Is Associated with the Brain Morphology in Superior Temporal Gyrus and Insula

Subjective well-being (SWB) is closely related to our physical and mental health. Existing studies show that neural or genetic basis underpins individual difference in SWB. Moreover, researchers have found high enrichment of SWB-related mutations in the central nervous system, but the relationship between the genetic architecture of SWB and brain morphology has not been explored. Considering the polygenic nature of SWB, in this study, we aim to establish a measure of additive genetic effect on SWB and explore its relationship to the brain anatomical structure. Based on the results of genome-wide association study (GWAS) on SWB, the polygenic scores (PGSs) of SWB at eight different thresholds were calculated in a large Chinese sample (N = 585). Then, we analyzed the associations between the PGSs of SWB and cortical thickness (CT) or gray matter volume (GMV) measured from 3.0-T structural imaging data. In whole-brain analyses, we found that a higher PGS was significantly associated with increased CT in the right superior temporal gyrus (STG) and GMV in the right insula, both of which are involved in social cognition and emotional processing. More importantly, these findings were repeatable at some different thresholds. The results may suggest that the brain morphology of right STG and insula is partly regulated by SWB-related genetic factors.

The neural correlates of well-being: A systematic review of the human neuroimaging and neuropsychological literature

What it means to be well and to achieve well-being is fundamental to the human condition. Scholars of many disciplines have attempted to define well-being and to investigate the behavioral and neural correlates of well-being. Despite many decades of inquiry into well-being, much remains unknown. The study of well-being has evolved over time, shifting in focus and methodology. Many recent investigations into well-being have taken a neuroscientific approach to try to bolster understanding of this complex construct. A growing body of literature has directly examined the association between well-being and the brain. The current review synthesizes the extant literature regarding the neural correlates of trait-like well-being (i.e., the propensity to live according to one's true nature). Although reported associations between well-being and the brain varied, some notable patterns were evidenced in the literature. In particular, the strongest and most consistent association emerged between well-being and the anterior cingulate cortex. In addition, patterns of association between well-being and the orbitofrontal cortex, posterior cingulate cortex, superior temporal gyrus, and thalamus emerged. These regions largely comprise the salience and default mode networks, suggesting a possible relationship between well-being and brain networks involved in the integration of relevant and significant stimuli. Various methodological concerns are addressed and recommendations for future research are discussed.

The role of hedonics in the Human Affectome

Experiencing pleasure and displeasure is a fundamental part of life. Hedonics guide behavior, affect decision-making, induce learning, and much more. As the positive and negative valence of feelings, hedonics are core processes that accompany emotion, motivation, and bodily states. Here, the affective neuroscience of pleasure and displeasure that has largely focused on the investigation of reward and pain processing, is reviewed. We describe the neurobiological systems of hedonics and factors that modulate hedonic experiences (e.g., cognition, learning, sensory input). Further, we review maladaptive and adaptive pleasure and displeasure functions in mental disorders and well-being, as well as the experience of aesthetics. As a centerpiece of the Human Affectome Project, language used to express pleasure and displeasure was also analyzed, and showed that most of these analyzed words overlap with expressions of emotions, actions, and bodily states. Our review shows that hedonics are typically investigated as processes that accompany other functions, but the mechanisms of hedonics (as core processes) have not been fully elucidated.

Brain networks of happiness: dynamic functional connectivity among the default, cognitive and salience networks relates to subjective well-being

Subjective well-being (SWB) reflects the cognitive and emotional evaluations of an individual's life and plays an important role in individual's success in health, work and social relationships. Although previous studies have revealed the spontaneous brain activity underlying SWB, little is known about the relationship between brain network interactions and SWB. The present study investigated the static and dynamic functional connectivity among large-scale brain networks during resting state functional magnetic resonance imaging (fMRI) in relation to SWB in two large independent datasets. The results showed that SWB is negatively correlated with static functional connectivity between the salience network (SN) and the anterior default mode network (DMN). Dynamic functional network connectivity (dFNC) analysis found that SWB is negatively correlated with the fraction of time that participants spent in a brain state characterized by weak cross-network connectivity (between the DMN, SN and frontal-parietal network [FPN]) and strong within-network connectivity (within the DMN and within the FPN). This connectivity profile may account for the good mental adaptability and flexible information communication of people with high levels of SWB. The dFNC results were well replicated with different analysis parameters and further validated in an independent sample. Taken together, these findings reveal that the dynamic interaction between networks involved in self-reflection, emotional regulation and cognitive control underlies SWB.

The Positive Brain - Resting State Functional Connectivity in Highly Vital and Flourishing Individuals

The World Health Organization has defined health as “complete physical, mental and social well-being and not merely the absence of disease or infirmity” (World Health Organization, 1948). An increasing number of studies have therefore started to investigate “the good life.” However, the underlying variation in brain activity has rarely been examined. The goal of this study was to assess differences in resting state functional connectivity (RSFC) between regular healthy individuals and healthy individuals with a high occurrence of flourishing and subjective vitality. Together, flourishing, a broad measure of psycho-social functioning and subjective vitality, an organismic marker of subjective well-being comprise the phenomenological opposite of a major depressive disorder. Out of a group of 43 participants, 20 high-flourishing (highFl) and 18 high-vital (highSV) individuals underwent a 7-min resting state period, where cortical activity in posterior brain areas was assessed using functional near-infrared spectroscopy (fNIRS). Network-based statistics (NBS) of FC yielded significantly different FC patterns for the highFl and highSV individuals compared to their healthy comparison group. The networks converged at areas of the posterior default mode network and differed in hub nodes in the left middle temporal/fusiform gyrus (flourishing) and the left primary/secondary somatosensory cortex (subjective vitality). The attained networks are discussed with regard to recent neuroscientific findings for other well-being measures and potential mechanisms of action based on social information processing and body-related self-perception.

Pleasure attainment or self-realization: the balance between two forms of well-beings are encoded in default mode network

What is a good life and how it can be achieved is one of the fundamental issues. When considering a good life, there is a division between hedonic (pleasure attainment) and eudaimonic well-being (meaning pursuing and self-realization). However, an integrated approach that can compare the brain functional and structural differences of these two forms of well-being is lacking. Here, we investigated how the individual tendency to eudaimonic well-being relative to hedonic well-being, measured using eudaimonic and hedonic balance (EHB) index, is reflected in the functional and structural features of a key network of well-being—the default mode network (DMN). We found that EHB was positively correlated with functional connectivity of bilateral ventral medial prefrontal cortex within anterior DMN and bilateral precuneus within posterior DMN. Brain morphometric analysis showed that EHB was also positively correlated with gray matter volume in left precuneus. These results demonstrated that the relative dominance of one form of well-being to the other is reflected in the morphometric characteristics and intrinsic functions of DMN.

Acute Affective Reactivity and Quality of Life in Older Adults with Amnestic Mild Cognitive Impairment: A Functional MRI Study

OBJECTIVES

Poor quality of life (QoL) is a major concern among older adults with amnestic mild cognitive impairment (MCI). Maladaptive affective regulation and its relevant frontal dysfunction that are often observed in older adults with MCI may provide an insight into the understanding of their QoL.

METHODS

In this case-controlled study, participants (MCI patients, N = 18; healthy comparisons [HC], N = 21) completed cognitive tasks, and underwent resting-state functional magnetic resonance imaging (rs-fMRI) immediately before and after the tasks. The amplitude of low-frequency fluctuations (ALFF) of rs-fMRI signals was calculated to examine the brain's spontaneous activity. The change in valence from the Self-Assessment Manikin indexed affective reactivity. QoL was assessed using Quality of Life-AD measure. Multiple mediator model was used to examine the mediating effect of frontal regions' ALFF reactivity between the affective reactivity and QoL.

RESULTS

The MCI group had significantly worse QoL and more negative affective reactivity than HC group. Less negative affective reactivity was significantly associated with better QoL in MCI not HC. ALFF in the anterior cingulate cortex, medial prefrontal cortex (MPFC), and superior frontal gyrus (SFG) increased significantly less after cognitive tasks in MCI than HC. For the entire sample, greater increases of ALFF in MPFC and SFG were significantly associated with better QoL, and SFG alone significantly mediated the association between affective reactivity and QoL.

CONCLUSIONS

Enhancing SFG activation, especially among those with MCI, may provide a therapeutic target for addressing the negative impact of maladaptive affective regulation on QoL.

Amplitude of Low-Frequency Fluctuations During Resting State Differentially Predicts Authentic and Hubristic Pride

OBJECTIVE

Pride is an important, self-conscious emotion composed of two distinct conceptual facets: arrogant, egotistic "hubristic pride," and pro-social, achievement-oriented "authentic pride." However, little is known about the neural basis of the two facets of pride. Here, we investigated the association between spontaneous brain activity and these two facets of pride in resting state.

METHOD

We measured 276 participants on authentic and hubristic pride. The fractional amplitude of low-frequency fluctuations (fALFF) was used to identify pride-related regions.

RESULTS

The results revealed individual differences in authentic pride were associated with the fALFF in the bilateral superior temporal gyrus (STG), which has been implicated in social processing. In contrast, individual differences in hubristic pride were associated with the fALFF in the left orbitofrontal cortex (OFC) and posterior cingulate cortex (PCC), which have been implicated in self-referential and reward processing.

CONCLUSIONS

Together, our results provide initial evidence for the distinct neural substrates for authentic and hubristic pride.

Multimodal analysis of cortical chemoarchitecture and macroscale fMRI resting-state functional connectivity

The cerebral cortex is well known to display a large variation in excitatory and inhibitory chemoarchitecture, but the effect of this variation on global scale functional neural communication and synchronization patterns remains less well understood. Here, we provide evidence of the chemoarchitecture of cortical regions to be associated with large-scale region-to-region resting-state functional connectivity. We assessed the excitatory versus inhibitory chemoarchitecture of cortical areas as an ExIn ratio between receptor density mappings of excitatory (AMPA, M1 ) and inhibitory (GABAA , M2 ) receptors, computed on the basis of data collated from pioneering studies of autoradiography mappings as present in literature of the human (2 datasets) and macaque (1 dataset) cortex. Cortical variation in ExIn ratio significantly correlated with total level of functional connectivity as derived from resting-state functional connectivity recordings of cortical areas across all three datasets (human I: P = 0.0004; human II: P = 0.0008; macaque: P = 0.0007), suggesting cortical areas with an overall more excitatory character to show higher levels of intrinsic functional connectivity during resting-state. Our findings are indicative of the microscale chemoarchitecture of cortical regions to be related to resting-state fMRI connectivity patterns at the global system's level of connectome organization. Hum Brain Mapp 37:3103-3113, 2016. © 2016 Wiley Periodicals, Inc.

The Hierarchical Structure of the Face Network Revealed by Its Functional Connectivity Pattern

A major principle of human brain organization is "integrating" some regions into networks while "segregating" other sets of regions into separate networks. However, little is known about the cognitive function of the integration and segregation of brain networks. Here, we examined the well-studied brain network for face processing, and asked whether the integration and segregation of the face network (FN) are related to face recognition performance. To do so, we used a voxel-based global brain connectivity method based on resting-state fMRI to characterize the within-network connectivity (WNC) and the between-network connectivity (BNC) of the FN. We found that 95.4% of voxels in the FN had a significantly stronger WNC than BNC, suggesting that the FN is a relatively encapsulated network. Importantly, individuals with a stronger WNC (i.e., integration) in the right fusiform face area were better at recognizing faces, whereas individuals with a weaker BNC (i.e., segregation) in the right occipital face area performed better in the face recognition tasks. In short, our study not only demonstrates the behavioral relevance of integration and segregation of the FN but also provides evidence supporting functional division of labor between the occipital face area and fusiform face area in the hierarchically organized FN. Significance statement: Although the integration and segregation are major principles of human brain organization, little is known about whether they support the cognitive processes. By correlating the within-network connectivity (WNC) and between-network connectivity (BNC) of the face network with face recognition performance, we found that individuals with stronger WNC in the right fusiform face area or weaker BNC in the right occipital face area were better at recognizing faces. Our study not only demonstrates the behavioral relevance of the integration and segregation but also provides evidence supporting functional division of labor between the occipital face area and fusiform face area in the hierarchically organized face network.

Functional integration of the posterior superior temporal sulcus correlates with facial expression recognition

Face perception is essential for daily and social activities. Neuroimaging studies have revealed a distributed face network (FN) consisting of multiple regions that exhibit preferential responses to invariant or changeable facial information. However, our understanding about how these regions work collaboratively to facilitate facial information processing is limited. Here, we focused on changeable facial information processing, and investigated how the functional integration of the FN is related to the performance of facial expression recognition. To do so, we first defined the FN as voxels that responded more strongly to faces than objects, and then used a voxel-based global brain connectivity method based on resting-state fMRI to characterize the within-network connectivity (WNC) of each voxel in the FN. By relating the WNC and performance in the "Reading the Mind in the Eyes" Test across participants, we found that individuals with stronger WNC in the right posterior superior temporal sulcus (rpSTS) were better at recognizing facial expressions. Further, the resting-state functional connectivity (FC) between the rpSTS and right occipital face area (rOFA), early visual cortex (EVC), and bilateral STS were positively correlated with the ability of facial expression recognition, and the FCs of EVC-pSTS and OFA-pSTS contributed independently to facial expression recognition. In short, our study highlights the behavioral significance of intrinsic functional integration of the FN in facial expression processing, and provides evidence for the hub-like role of the rpSTS for facial expression recognition. Hum Brain Mapp 37:1930-1940, 2016. © 2016 Wiley Periodicals, Inc.

Discriminability of personality profiles in isolated and Co-morbid marijuana and nicotine users

Specific personality traits have been linked with substance use disorders (SUDs), genetic mechanisms, and brain systems. Thus, determining the specificity of personality traits to types of SUD can advance the field towards defining SUD endophenotypes as well as understanding the brain systems involved for the development of novel treatments. Disentangling these factors is particularly important in highly co morbid SUDs, such as marijuana and nicotine use, so treatment can occur effectively for both. This study evaluated personality traits that distinguish isolated and co-morbid use of marijuana and nicotine. To that end, we collected the NEO Five Factor Inventory in participants who used marijuana-only (n=59), nicotine-only (n=27), both marijuana and nicotine (n=28), and in non-using controls (n=28). We used factor analyses to identify personality profiles, which are linear combinations of the five NEO Factors. We then conducted Receiver Operating Characteristics (ROC) curve analysis to test accuracy of the personality factors in discriminating isolated and co-morbid marijuana and nicotine users from each other. ROC curve analysis distinguished the four groups based on their NEO personality patterns. Results showed that NEO Factor 2 (openness, extraversion, agreeableness) discriminated marijuana and marijuana+nicotine users from controls and nicotine-only users with high predictability. Additional ANOVA results showed that the openness dimension discriminated marijuana users from nicotine users. These findings suggest that personality dimensions distinguish marijuana users from nicotine users and should be considered in prevention strategies.

A test-retest dataset for assessing long-term reliability of brain morphology and resting-state brain activity

We present a test-retest dataset for evaluation of long-term reliability of measures from structural and resting-state functional magnetic resonance imaging (sMRI and rfMRI) scans. The repeated scan dataset was collected from 61 healthy adults in two sessions using highly similar imaging parameters at an interval of 103-189 days. However, as the imaging parameters were not completely identical, the reliability estimated from this dataset shall reflect the lower bounds of the true reliability of sMRI/rfMRI measures. Furthermore, in conjunction with other test-retest datasets, our dataset may help explore the impact of different imaging parameters on reliability of sMRI/rfMRI measures, which is especially critical for assessing datasets collected from multiple centers. In addition, intelligence quotient (IQ) was measured for each participant using Raven's Advanced Progressive Matrices. The data can thus be used for purposes other than assessing reliability of sMRI/rfMRI alone. For example, data from each single session could be used to associate structural and functional measures of the brain with the IQ metrics to explore brain-IQ association.

Loneliness, eudaimonia, and the human conserved transcriptional response to adversity

BACKGROUND

Chronic social adversity activates a conserved transcriptional response to adversity (CTRA) marked by increased expression of pro-inflammatory genes and decreased expression of antiviral- and antibody-related genes. Recent findings suggest that some psychological resilience factors may help buffer CTRA activation, but the relative impact of resilience and adversity factors remains poorly understood. Here we examined the relative strength of CTRA association for the two best-established psychological correlates of CTRA gene expression-the risk factor of perceived social isolation (loneliness) and the resilience factor of eudaimonic well-being (purpose and meaning in life).

METHODS

Peripheral blood samples and validated measures of loneliness and eudaimonic well-being were analyzed in 108 community-dwelling older adults participating in the longitudinal US Health and Retirement Study (56% female, mean age 73). Mixed effect linear model analyses quantified the strength of association between CTRA gene expression and measures of loneliness and eudaimonic well-being in separate and joint analyses.

RESULTS

As in previous studies, separate analyses found CTRA gene expression to be up-regulated in association with loneliness and down-regulated in association with eudaimonic well-being. In joint analyses, effects of loneliness were completely abrogated whereas eudaimonic well-being continued to associate with CTRA down-regulation. Similar eudaimonia-dominant effects were observed for positive and negative affect, optimism and pessimism, and anxiety symptoms. All results were independent of demographic and behavioral health risk factors.

CONCLUSIONS

Eudaimonic well-being may have the potential to compensate for the adverse impact of loneliness on CTRA gene expression. Findings suggest a novel approach to targeting the health risks associated with social isolation by promoting purpose and meaning in life.

Resting-state functional connectivity of the default mode network associated with happiness

Happiness refers to people's cognitive and affective evaluation of their life. Why are some people happier than others? One reason might be that unhappy people are prone to ruminate more than happy people. The default mode network (DMN) is normally active during rest and is implicated in rumination. We hypothesized that unhappiness may be associated with increased default-mode functional connectivity during rest, including the medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC) and inferior parietal lobule (IPL). The hyperconnectivity of these areas may be associated with higher levels of rumination. One hundred forty-eight healthy participants underwent a resting-state fMRI scan. A group-independent component analysis identified the DMNs. Results indicated increased functional connectivity in the DMN was associated with lower levels of happiness. Specifically, relative to happy people, unhappy people exhibited greater functional connectivity in the anterior medial cortex (bilateral MPFC), posterior medial cortex regions (bilateral PCC) and posterior parietal cortex (left IPL). Moreover, the increased functional connectivity of the MPFC, PCC and IPL, correlated positively with the inclination to ruminate. These results highlight the important role of the DMN in the neural correlates of happiness, and suggest that rumination may play an important role in people's perceived happiness.

Mother's but not father's education predicts general fluid intelligence in emerging adulthood: Behavioral and neuroanatomical evidence

Lower parental education impairs cognitive abilities of their offspring such as general fluid intelligence dependent on the prefrontal cortex (PFC), but the independent contribution of mother's and father's education is unknown. We used an individual difference approach to test whether mother's and father's education independently affected general fluid intelligence in emerging adulthood at both the behavioral and neural level. Behaviorally, mother's but not father's education accounted for unique variance in general fluid intelligence in emerging adulthood (assessed by the Raven's advanced progressive matrices). Neurally, the whole-brain correlation analysis revealed that the regional gray matter volume (rGMV) in the medial PFC was related to both mother's education and general fluid intelligence but not father's education. Furthermore, after controlling for mother's education, the association between general fluid intelligence and the rGMV in medial PFC was no longer significant, indicating that mother's education plays an important role in influencing the structure of the medial PFC associated with general fluid intelligence. Taken together, our study provides the first behavioral and neural evidence that mother's education is a more important determinant of general cognitive ability in emerging adulthood than father's education.

Culture, inequality, and health: evidence from the MIDUS and MIDJA comparison

This article seeks to forge scientific connections between three overarching themes (culture, inequality, health). Although the influence of cultural context on human experience has gained notable research prominence, it has rarely embraced another large arena of science focused on the influence social hierarchies have on how well and how long people live. That literature is increasingly focused psychosocial factors, working interactively with biological and brain-based mechanisms, to account for why those with low socioeconomic standing have poorer health. Our central question is whether and how these processes might vary by cultural context. We draw on emerging findings from two parallel studies, Midlife in the U.S. and Midlife in Japan, to illustrate the cultural specificity evident in how psychosocial and neurobiological factors are linked with each other as well as how position in social hierarchies matters for psychological experience and biology. We conclude with suggestions for future multidisciplinary research seeking to understand how social hierarchies matter for people's health, albeit in ways that may possibly differ across cultural contexts.