Brain Functional Basis of Subjective Well-being During Negative Facial Emotion Processing Task-Based fMRI

Effects of repetitive transcranial magnetic stimulation on fear of cancer recurrence and its underlying neuromechanism

Introduction

Many breast cancer patients suffer from fear of cancer recurrence (FCR). However, effective physical intervention for FCR has been scarce. Previous studies have confirmed that repetitive transcranial magnetic stimulation (rTMS) can help improve patients' anxiety, depression, fear, and stress level. Therefore, this study aims to assess the efficacy of rTMS in the treatment of FCR in breast cancer patients and explore its underlying neural mechanism.

Methods and analysis

and analysis: Fifty breast cancer patients with high FCR (FCR total score >27), and fifty age- and gender-matched patients with low FCR (FCR total score <7) will be recruited to participate in this study. Patients in the high FCR group will be randomly assigned to receive 4-week low-frequency rTMS targeting the right dorsolateral prefrontal cortex (rDLPFC) + treatment as usual (TAU) (n = 25), or to receive sham stimulation + TAU (n = 25). Patients in the low FCR group will only receive TAU. All participants will take a baseline fMRI scan to examine the local activities and interactions of brain activity between the prefrontal cortex (DLPFC), amygdala and hippocampus. Fear of Cancer Recurrence Questionnaire (FCRQ7), Patient Health Questionnaire (PHQ9), Generalize Anxiety Disorder (GAD7), Numeric Rating Scale (NRS), and Insomnia Severity Index (ISI7) will be used to measure an individual's FCR, depression, anxiety, pain, and insomnia symptoms at week 0 (baseline), week 4 (the end of intervention), week 5 (1 week post-treatment), week 8 (1 month post-treatment), and week 16 (3 months post-treatment). Participants in the high FCR group will receive a post-treatment fMRI scan within 24 h after intervention to explore the neural mechanisms of rTMS treatment. The primary outcome of the study, whether the rTMS intervention is sufficient in relieving FCR in breast cancer patients, is measured by FCRQ7. Additionally, task activation, local activity and functional connectivity of the DLPFC, amygdala and hippocampus will be compared, between high and low FCR group, and before and after treatment.

Discussion

Studies have shown that low-frequency rTMS can be used to treat patient's FCR. However, there is a lack of relevant evidence to support the efficacy of rTMS on FCR in cancer patients, and the neural mechanisms underlying the effects of rTMS on FCR need to be further investigated.

Ethics and dissemination

Ethical approval for the study has been obtained from the Ethics Committee of Guangdong Provincial People's Hospital (reference number: KY-N-2022-136-01). The results of the investigation will be published in scientific papers. The data from the investigation will be made available online if necessary.

Trial registration

NCT05881889 (ClinicalTrials.gov). Date of registration: May 31, 2023.

Association Between Negative Affect and Perceived Mortality Threat During the COVID-19 Pandemic: The Role of Brain Activity and Connectivity

The prevalence of the novel coronavirus (COVID-19) has been considered a major threat to physical and mental health around the world, causing great pressure and mortality threat to most people. The current study aimed to investigate the neurological markers underlying the relationship between perceived mortality threat (PMT) and negative affect (NA). We examined whether the regional amplitude of low-frequency fluctuations (ALFF) and resting-state functional connectivity (RSFC) before the COVID-19 outbreak (October 2019 to December 2019, wave 1) were predictive for NA and PMT during the mid-term of the COVID-19 pandemic (February 22 to 28, 2020, wave 2) among 603 young adults (age range 17-22, 70.8% females). Results indicated that PMT was associated with spontaneous activity in several regions (e.g., inferior temporal gyrus, medial occipital gyrus, medial frontal gyrus, angular gyrus, and cerebellum) and their RSFC with the distributed regions of the default mode network and cognitive control network. Furthermore, longitudinal mediation models showed that ALFF in the cerebellum, medial occipital gyrus, medial frontal gyrus, and angular gyrus (wave 1) predicted PMT (wave 2) through NA (wave 2). These findings revealed functional neural markers of PMT and suggest candidate mechanisms for explaining the complex relationship between NA and mental/neural processing related to PMT in the circumstance of a major crisis.

Well-being is associated with cortical thickness network topology of human brain

BACKGROUND

Living a happy and meaningful life is an eternal topic in positive psychology, which is crucial for individuals' physical and mental health as well as social functioning. Well-being can be subdivided into pleasure attainment related hedonic well-being or emotional well-being, and self-actualization related eudaimonic well-being or psychological well-being plus social well-being. Previous studies have mostly focused on human brain morphological and functional mechanisms underlying different dimensions of well-being, but no study explored brain network mechanisms of well-being, especially in terms of topological properties of human brain morphological similarity network.

METHODS

Therefore, in the study, we collected 65 datasets including magnetic resonance imaging (MRI) and well-being data, and constructed human brain morphological network based on morphological distribution similarity of cortical thickness to explore the correlations between topological properties including network efficiency and centrality and different dimensions of well-being.

RESULTS

We found emotional well-being was negatively correlated with betweenness centrality in the visual network but positively correlated with eigenvector centrality in the precentral sulcus, while the total score of well-being was positively correlated with local efficiency in the posterior cingulate cortex of cortical thickness network.

CONCLUSIONS

Our findings demonstrated that different dimensions of well-being corresponded to different cortical hierarchies: hedonic well-being was involved in more preliminary cognitive processing stages including perceptual and attentional information processing, while hedonic and eudaimonic well-being might share common morphological similarity network mechanisms in the subsequent advanced cognitive processing stages.

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.

Wellbeing and brain structure: A comprehensive phenotypic and genetic study of image-derived phenotypes in the UK Biobank

Wellbeing, an important component of mental health, is influenced by genetic and environmental factors. Previous association studies between brain structure and wellbeing have typically focused on volumetric measures and employed small cohorts. Using the UK Biobank Resource, we explored the relationships between wellbeing and brain morphometrics (volume, thickness and surface area) at both phenotypic and genetic levels. The sample comprised 38,982 participants with neuroimaging and wellbeing phenotype data, of which 19,234 had genotypes from which wellbeing polygenic scores (PGS) were calculated. We examined the association of wellbeing phenotype and PGS with all brain regions (including cortical, subcortical, brainstem and cerebellar regions) using multiple linear models, including (1) basic neuroimaging covariates and (2) additional demographic factors that may synergistically impact wellbeing and its neural correlates. Genetic correlations between genomic variants influencing wellbeing and brain structure were also investigated. Small but significant associations between wellbeing and volumes of several cerebellar structures (β = 0.015-0.029, PFDR  = 0.007-3.8 × 10-9 ), brainstem, nucleus accumbens and caudate were found. Cortical associations with wellbeing included volume of right lateral occipital, thickness of bilateral lateral occipital and cuneus, and surface area of left superior parietal, supramarginal and pre-/post-central regions. Wellbeing-PGS was associated with cerebellar volumes and supramarginal surface area. Small mediation effects of wellbeing phenotype and PGS on right VIIIb cerebellum were evident. No genetic correlation was found between wellbeing and brain morphometric measures. We provide a comprehensive overview of wellbeing-related brain morphometric variation. Notably, small effect sizes reflect the multifaceted nature of this concept.

TWIN-10: protocol for a 10-year longitudinal twin study of the neuroscience of mental well-being and resilience

INTRODUCTION

Mental well-being is a core component of mental health, and resilience is a key process of positive adaptive recovery following adversity. However, we lack an understanding of the neural mechanisms that contribute to individual variation in the trajectories of well-being and resilience relative to risk. Genetic and/or environmental factors may also modulate these mechanisms. The aim of the TWIN-10 Study is to characterise the trajectories of well-being and resilience over 12 years across four timepoints (baseline, 1 year, 10 years, 12 years) in 1669 Australian adult twins of European ancestry (to account for genetic stratification effects). To this end, we integrate data across genetics, environment, psychological self-report, neurocognitive performance and brain function measures of well-being and resilience.

METHODS AND ANALYSIS

Twins who took part in the baseline TWIN-E Study will be invited back to participate in the TWIN-10 Study, at 10-year and 12-year follow-up timepoints. Participants will complete an online battery of psychological self-reports, computerised behavioural assessments of neurocognitive functions and MRI testing of the brain structure and function during resting and task-evoked scans. These measures will be used as predictors of the risk versus resilience trajectory groups defined by their changing levels of well-being and illness symptoms over time as a function of trauma exposure. Structural equation models will be used to examine the association between the predictors and trajectory groups of resilience and risk over time. Univariate and multivariate twin modelling will be used to determine heritability of the measures, as well as the shared versus unique genetic and environmental contributions.

ETHICS AND DISSEMINATION

This study involves human participants. This study was approved by the University of New South Wales Human Research Ethics Committee (HC180403) and the Scientific Management Panel of Neuroscience Research Australia Imaging (CX2019-05). Results will be disseminated through publications and presentations to the public and the academic community. Participants gave informed consent to participate in the study before taking part.

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.

Deconstructing Gender Differences in Experienced Well-Being Among Older Adults in the Developing World: The Roles of Time Use and Activity-Specific Affective Experiences

Due to declining fertility rates and increasing longevity, the world is growing older. Improving the quality of life of older adults, and not merely preventing deaths, is thus becoming an important objective of public policies. It is, therefore, urgent to understand the key dimensions of older adults' subjective well-being as well as their main drivers. Women represent a large proportion of the older population, and existing evidence suggests that they may be particularly vulnerable, especially in the developing world. Analyzing potential gender differences in experienced well-being in older adults is hence crucial. We exploit information on time use and activity-specific emotional experiences from the abbreviated version of the day reconstruction method contained in the WHO Study on Global Ageing and Adult Health (SAGE), focusing on five developing countries. We first quantify gender differences in experienced well-being among older adults, which we then deconstruct into corresponding differences in time use and activity-specific net affects. Adjusting for age only, our results indicate a gender gap in experienced well-being in favor of men. Yet, adjusting for additional individual characteristics and life circumstances beyond age weakens this association. Illustrative counterfactual analyses further suggest that gender differences in activity-specific net affects appear more important than differences in time use for explaining the disadvantage of older women. Our results suggest that women's lower affect in most activities is linked to the conditions under which these activities are performed, and in particular to the higher level of disability of older women compared to men of the same age.

Spatial Connectivity and Temporal Dynamic Functional Network Connectivity of Musical Emotions Evoked by Dynamically Changing Tempo

Music tempo is closely connected to listeners' musical emotion and multifunctional neural activities. Music with increasing tempo evokes higher emotional responses and music with decreasing tempo enhances relaxation. However, the neural substrate of emotion evoked by dynamically changing tempo is still unclear. To investigate the spatial connectivity and temporal dynamic functional network connectivity (dFNC) of musical emotion evoked by dynamically changing tempo, we collected dynamic emotional ratings and conducted group independent component analysis (ICA), sliding time window correlations, and k-means clustering to assess the FNC of emotion evoked by music with decreasing tempo (180-65 bpm) and increasing tempo (60-180 bpm). Music with decreasing tempo (with more stable dynamic valences) evoked higher valence than increasing tempo both with stronger independent components (ICs) in the default mode network (DMN) and sensorimotor network (SMN). The dFNC analysis showed that with time-decreasing FNC across the whole brain, emotion evoked by decreasing music was associated with strong spatial connectivity within the DMN and SMN. Meanwhile, it was associated with strong FNC between the DMN-frontoparietal network (FPN) and DMN-cingulate-opercular network (CON). The paired t-test showed that music with a decreasing tempo evokes stronger activation of ICs within DMN and SMN than that with an increasing tempo, which indicated that faster music is more likely to enhance listeners' emotions with multifunctional brain activities even when the tempo is slowing down. With increasing FNC across the whole brain, music with an increasing tempo was associated with strong connectivity within FPN; time-decreasing connectivity was found within CON, SMN, VIS, and between CON and SMN, which explained its unstable valence during the dynamic valence rating. Overall, the FNC can help uncover the spatial and temporal neural substrates of musical emotions evoked by dynamically changing tempi.

Longitudinal Characterization of Blood-Brain Barrier Permeability after Experimental Traumatic Brain Injury by In Vivo 2-Photon Microscopy

Vasogenic brain edema (VBE) formation remains an important factor determining the fate of patients with traumatic brain injury (TBI). The spatial and temporal development of VBE, however, remains poorly understood because of the lack of sufficiently sensitive measurement techniques. To close this knowledge gap, we directly visualized the full time course of vascular leakage after TBI by in vivo 2-photon microscopy (2-PM). Male C57BL/6 mice (n = 6/group, 6-8 weeks old) were assigned randomly to sham operation or brain trauma by controlled cortical impact. A cranial window was prepared, and tetramethylrhodamine-dextran (TMRM, MW 40,000 Da) was injected intravenously to visualize blood plasma 4 h, 24 h, 48 h, 72 h, or seven days after surgery or trauma. Three regions with increasing distance to the primary contusion were investigated up to a depth of 300 μm by 2-PM. No TMRM extravasation was detected in sham-operated mice, while already 4 h after TBI vascular leakage was significantly increased (p < 0.05 vs. sham) and reached its maximum at 48 h after injury. Vascular leakage was most pronounced in the vicinity of the contusion. The rate of extravasation showed a biphasic pattern, peaking 4 h and 48-72 h after trauma. Taken together, longitudinal quantification of vascular leakage after TBI in vivo demonstrates that VBE formation after TBI develops in a biphasic manner suggestive of acute and delayed mechanisms. Further studies using the currently developed dynamic in vivo imaging modalities are needed to investigate these mechanisms and potential therapeutic strategies in more detail.

Brain structural changes in CADASIL patients: A morphometric magnetic resonance imaging study

BACKGROUND

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a subcortical, inherited, cerebral small vessel disease. Several studies have revealed the involvement of specific cortical regions. However, the structural brain alterations and their clinical correlations remain largely undetermined.

METHODS

We evaluated 22 CADASIL patients and 22 age- and sex-matched healthy controls. We used surface- and voxel-based morphometric data derived from 3.0-T magnetic resonance imaging (MRI) to explore structural changes in gray and white matter. We calculated Pearson correlations between such data and clinical and MRI metrics.

RESULTS

Compared with controls, CADASIL patients exhibited significantly decreased cortical thickness in the left supramarginal gyrus, superior temporal gyrus, transverse temporal gyrus, insula, lateral orbitofrontal gyrus, isthmus cingulate gyrus and precentral gyrus. An extensive decrease in the white (but not gray) matter volume was also evident, predominantly in the frontal, parietal, temporal, and occipital lobes. The number of previous strokes or transient ischemic attacks was negatively associated with the cortical thickness of the left pars opercularis and right posterior cingulate gyrus.

CONCLUSION

Reductions in cortical thickness and white matter volume were evident in CADASIL patients compared with controls, and higher numbers of strokes and transient ischemic attacks were associated with regional cortical thinning.