Gray Matter Volume Research Articles

Long-Term Cerebellar Consequences of Post-traumatic Brain Injury Assessed by MRI With Diffusion Tensor Imaging

BACKGROUND AND OBJECTIVES: Post-traumatic brain injury (TBI) lesions, which combine brain atrophy and white matter injuries, can lead to progressive post-traumatic encephalopathy. However, the specific involvement of the cerebellum, which participates in cognitive, executive, and sensory functions, has been little studied. The aim of this work was to explore the long-term cerebellar consequences of severe TBI. METHODS: In this retrospective study, patients included were hospitalized for a severe TBI and reassessed after discharge with a clinical examination and a MRI with diffusion tensor imaging. Patients were compared with a population of healthy volunteers. For a subgroup of this cohort, we analyzed the evolution of late post-TBI lesions on MRI up to 10 years after TBI. RESULTS: Ninety-seven patients reassessed 5 [3; 6] years after the TBI were included. Volume loss was revealed in the whole cerebellum (P = .01) and especially in the anterior lobe (P < .005) with a decrease in grey matter volume (P = 6.10−3). The mean diffusivity was increased in 4 cerebellar areas which are the right lower, right upper, left lower, and left upper cerebellar peduncles while the fractional anisotropy was decreased in all studied areas (P < 10−3). The longitudinal analysis (n = 17 patients) showed no progression of MRI lesions beyond the acute phase. CONCLUSION: This work shows that even if direct cerebellar damage is rare, long-term post-TBI cerebellar lesions can be observed. Therefore, clinical correlates of cerebellar lesions should be considered more systematically.

The association between childhood adversity and hippocampal volumes is moderated by romantic relationship experiences

AbstractReduced hippocampal volumes are a feature of many mental disorders. Childhood maltreatment is a known risk factor for the development of psychopathology and has consistently been linked to hippocampal volume reductions in adults, but not in children and adolescents. We propose that maltreatment‐related difficulties in coping with developmental tasks in adolescence and young adulthood might underlie the delayed emergence of hippocampal volume reductions in maltreated individuals. In a study with 196 healthy young adults (mean age [years]: 24.0 ± 3.2, 50% female, 20.6% living with a partner (missings: n = 2)), we investigated the interaction between childhood maltreatment (Childhood Trauma Screener) and the breakup of a steady romantic relationship (List of Threatening Experiences Questionnaire) on hippocampal magnetic resonance imaging grey matter volumes. The experience of a romantic relationship breakup moderated the association between childhood maltreatment and bilateral hippocampal volumes, revealing more negative associations with hippocampal volumes in participants with at least one breakup compared to those with no breakup experience (right hippocampus: β = − 0.05 ± 0.02, p = 0.031, p (FDR) = 0.031; left hippocampus: β = −0.06 ± 0.02, p = 0.005, p (FDR) = 0.009). Moreover, our findings provide some evidence that childhood maltreatment is related to smaller bilateral hippocampal volumes only in those adults who suffered from a relationship breakup (right hippocampus: β = −0.23 ± 0.10, p = 0.018, p (FDR) = 0.018; left hippocampus: β = −0.24 ± 0.10, p = 0.016, p (FDR) = 0.018;). Our study highlights the interaction of adult social bonds with early adversity on vulnerability to psychopathology.

Male Homosexuality: Is It Nature or Nurture?

Abstract: This is an overview of nature and nurture arguments for male homosexuality based on the literature review. This article summarized and discussed both sides of nature and nurture perspectives and how they may contribute to the development of male homosexuality. From the nature perspective, the genetic, brain structure, and evolutionary arguments are included. From the nurture perspective, the birth order and family dynamics are mentioned. Both the nature and nurture aspects seem to play an important role in order to explain homosexuality. It is suggested that for future studies in this field, researchers may explore and compare the evolutionary connection of female and male homosexuality. In addition, the grey matter volume (GMV) in different brain regions seems to be a contributor to homosexuality; further examining the connection between the brain regions function and homosexuality may be necessary.

Gene-environment interactions in the influence of maternal education on adolescent neurodevelopment using ABCD study.

Maternal education was strongly correlated with adolescent brain morphology, cognitive performances, and mental health. However, the molecular basis for the effects of maternal education on the structural neurodevelopment remains unknown. Here, we conducted gene-environment-wide interaction study using the Adolescent Brain Cognitive Development cohort. Seven genomic loci with significant gene-environment interactions (G×E) on regional gray matter volumes were identified, with enriched biological functions related to metabolic process, inflammatory process, and synaptic plasticity. Additionally, genetic overlapping results with behavioral and disease-related phenotypes indicated shared biological mechanism between maternal education modified neurodevelopment and related behavioral traits. Finally, by decomposing the multidimensional components of maternal education, we found that socioeconomic status, rather than family environment, played a more important role in modifying the genetic effects on neurodevelopment. In summary, our study provided analytical evidence for G×E effects regarding adolescent neurodevelopment and explored potential biological mechanisms as well as social mechanisms through which maternal education could modify the genetic effects on regional brain development.

Deep Learning-Based Pediatric Brain Region Segmentation and Volumetric Analysis for General Growth Pattern in Healthy Children.

To establish a quantitative reference for brain structural changes in children with neurological disorders, we employed deep learning technique to brain region segmentation and volumetric analysis within a cohort of healthy children. In this study, we recruited 312 participants aged 1.5 to 14.5years (210 boys and 102 girls), dividing them into five age groups. High-resolution structural T1-weighted images were obtained, and an established toolkit utilizing deep learning algorithms was employed for brain region segmentation. For each age group, the volumes of gray matter and white matter, along with the thickness and surface area of the cortex, were calculated and compared between boys and girls. The results indicated that the volumes of gray matter and white matter in both bilateral cerebral hemispheres, as well as the total brain volume, increased with age. Furthermore, the volumes of the left and right hippocampus, amygdala, and thalamus also demonstrated an increase as age progressed. Conversely, cortical thickness and surface area decreased with age. Our findings provide a quantitative reference for understanding brain structural changes in children with neurological disorders.

Cortical structural network characteristics in non-cognitive impairment end-stage renal disease

ObjectiveExplore alterations in topological features of gray matter volume (GMV) and structural networks in non-cognitive impairment end-stage renal disease (Non-CI ESRD).Materials and methodsUtilizing graph theory, we collected structural magnetic resonance imaging (sMRI) data from 38 Non-CI ESRD patients and 50 normal controls (NC). We compared, and extracted the GMV across subject groups, constructed corresponding structural covariance networks (SCNs), and investigated the alterations in SCNs feature parameters between groups.ResultsIn Non-CI ESRD patients, The GMV were reduced in several brain regions, predominantly on the left side (p < 0.05, FWE correction). The small-world network characteristics of the patient group’s brain networks showed a tendency toward regular. In a few densities, global network parameters, transitivity, (p < 0.05) was significantly increased in the ESRD group. Regional network measurements revealed inconsistent changes in regional efficiency across different brain areas. In the analysis of network hubs, the right temporal pole is likely a compensatory hub for Non-CI ESRD patients. The SCNs in Non-CI ESRD patients demonstrated reduced topological stability against targeted attacks.ConclusionThis study reveals that patients with renal failure exhibited subtle changes in brain network characteristics even before a decline in cognitive scores. These changes involve compensatory activation in certain brain regions, which enhances network transitivity to maintain the efficiency of whole-brain network information integration without significant loss. Additionally, the SCNs characteristics can serve as a neuroanatomical marker for brain alterations in Non-CI ESRD patients, offering new insights into the mechanisms of early brain injury in ESRD patients.

Specific structural changes in Parkinson’s disease-related olfactory dysfunction compared to others forms of olfactory dysfunction

ContextOlfactory dysfunction (OD) is a common early symptom of Parkinson’s disease (PD). However, OD is not specific to PD, as approximatively 20% of the general population exhibit different forms of OD. To use olfactory measures for early Parkinson screening, it is crucial to distinguish PD-related OD from Non-Parkinsonian OD (NPOD).Objectives and hypothesisThis study aimed to compare the structural changes associated with PD-related OD (n = 15) with NPOD (n = 15), focusing on gray matter volumes and white matter fiber integrity in chemosensory regions. We hypothesized that PD-related OD presents specific structural alterations in these regions.MethodsParticipants underwent a 3 T MRI scan, which included anatomical T1 and diffusion-weighted imaging. Gray and white matter integrity were assessed using both whole-brain analyses (voxel-based morphometry—VBM and tract-based spatial statistics—TBSS, respectively) and localized approaches, including regions of interest and tractography.ResultsPD patients exhibited significantly higher gray matter volume in the left insula using restricted regions-of-interest analyses, while no other significant gray or white matter differences were found between groups.ConclusionStructural imaging of the gray matter, particularly the insula, but not of white matter, differentiates PD-related OD from NPOD.

Additive effects of cerebrovascular disease functional connectome phenotype and plasma p-tau181 on longitudinal neurodegeneration and cognitive outcomes.

We investigated the effects of multiple cerebrovascular disease (CeVD) neuroimaging markers on brain functional connectivity (FC), and how such CeVD-related FC changes interact with plasma phosphorylated tau (p-tau)181 (an Alzheimer's disease [AD] marker) to influence downstream neurodegeneration and cognitive changes. Multivariate associations among four CeVD markers and whole-brain FC in 529 participants across the dementia spectrum were examined using partial least squares correlation. Interactive effects of CeVD-related FC patterns and p-tau181 on longitudinal gray matter volume (GMV) and cognitive changes were investigated using linear mixed-effects models. We identified a brain FC phenotype associated with high CeVD burden across all markers. Further, expression of this general CeVD-related FC phenotype and p-tau181 contributed additively, but not synergistically, to baseline and longitudinal GMV and cognitive changes. Our findings suggest that CeVD exerts global effects on the brain connectome and highlight the additive nature of AD and CeVD on neurodegeneration and cognition. Effects of multiple cerebrovascular disease (CeVD) markers on functional connectivity were studied. A global network phenotype linked to high burden across CeVD markers was identified. CeVD phenotype and plasma phosphorylated tau 181 contributed additively to downstream outcomes.

Peripheral molecular and brain structural profile implicated stress activation and hyperoxidation in methamphetamine use disorder.

Methamphetamine use disorders (MUDs) cause widespread disruptions in metabolomic and immunologic processes, highlighting the need for new therapeutic approaches. The purpose of this study was to find molecular and neuroimaging biomarkers for methamphetamine addiction. In this study, we recruited 231 patients with MUD at varying stages of withdrawal and 40 healthy controls to quantify the blood levels of 52 molecules using enzyme-linked immunosorbent assay. The overall molecular disruption caused by methamphetamine was inversely related to withdrawal time (P = 0.0008), with partial recovery observed after 1 year of follow-up (P = 2.20 × 10-5). Molecules related to stress, immune activation, oxidative products, and cardiac injury were significantly elevated in all MUD groups, while antioxidation enzymes were downregulated. Additionally, the blood level of brain-derived neurotrophic factor was significantly correlated with gray matter volumes in nine brain regions (fusiform gyrus, orbitofrontal cortex, temporal pole, caudate, cerebellum crus, and vermis, adjusted P < 0.05) among patients with MUD. These findings suggest that patients with MUD exhibit elevated levels of immune response, stress, and oxidative stress, which are associated with brain structural abnormalities.

Age-related volume decrease in subcortical gray matter is a part of healthy brain aging in men.

With the global population aging, the number of individuals over 60 is expected to double by 2050. Brain volume increases until age 13, stabilizes between 18 and 35, then declines by 0.2% annually. Magnetic resonance imaging (MRI) studies highlight significant gray matter atrophy, necessitating differentiation between normal aging and neurodegeneration. This study assessed the impact of aging on subcortical gray matter in healthy males to identify biomarkers of physiological aging. A retrospective study of 106 healthy males who underwent brain MRI from 2012 to 2016, divided into two age groups: younger and older than 35years. MRI scans were performed using a 3T machine, and volumetric analysis was conducted with VolBrain software. Subcortical gray matter volumes were compared between groups. The Shapiro-Wilk test evaluated normality. Student's t-test and Mann-Whitney U test were used for statistical analysis, with significance defined as p < 0.05. Total intracranial volume was comparable between age groups (p = 0.527). Significant volume reductions (p < 0.05) were observed in subcortical gray matter structures, including the nucleus accumbens, caudate nucleus, globus pallidus, putamen, thalamus, and ventral diencephalon, particularly on the right side in the elderly group. Subcortical gray matter volume in healthy males shows significant differences between older and younger individuals (p < 0.05), with asymmetrical reduction and certain structures on the right aging more rapidly. These findings are significant for distinguishing healthy aging from neurodegeneration.

Abnormal changes of brain function and structure in patients with T2DM-related cognitive impairment: a neuroimaging meta-analysis and an independent validation.

Type 2 diabetes mellitus (T2DM) seriously threatens human health and the quality of life, cognitive impairment is considered as a common complication of T2DM. Neuroimaging meta-analysis found brain functional and structural abnormality in patients with T2DM. Therefore, the purpose of the meta-analysis was to identify brain regions of patients with T2DM-related cognitive impairment (T2DM-CI) where functional and structural indicators changed together or could not synchronize. A literature screening of neuroimaging studies on cognitive impairment in T2DM was conducted from 1 January 2007 to 26 May 2023 in PubMed, Web of Science, Cochrane Library, and Medline databases. The functional indicators we studied were amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo) and degree centrality (DC), while the structural indicator was gray matter (GM), which included gray matter volume (GMV) and cerebral cortical thickness. Studies reporting ALFF, ReHo, DC and GM abnormalities between T2DM-CI and healthy controls (HCs) were selected and their significant peak coordinates (x, y, z) and effect size (t-value) were extracted to perform a meta-analysis using anisotropic effect size sign differential mapping (AES-SDM) 5.15 software. Moreover, the brain regions with significant differences obtained from meta-analysis were saved as masks and then validated in our data. Total 19 studies and 20 datasets were involved in this study. Compared to HCs, combining ALFF, ReHo, and DC measurements, the brain activity of the left anterior cingulate/paracingulate gyri (ACC.L, BA24) in T2DM-CI patients increased significantly, while the brain activity of the left lingual gyrus (LING.L, BA18) in T2DM-CI patients decreased significantly. The GM indicator of the right superior temporal gyrus (STG.R, BA42) and left inferior occipital gyrus (IOG.L, BA19) in T2DM-CI patients decreased significantly. Meta-regression analysis showed the negative relationship between the brain activity reduction in LING.L and the percentage of female patients, as well as the negative relationship between GM reduction in IOG.L and T2DM duration. Furthermore, we validated a decrease in brain activity in the LING.L of T2DM-CI patients in our independent dataset. The decrease of brain activity in LING.L and the decrease of GM in IOG.L were closely related to visual impairment in T2DM-CI patients. These abnormal brain regions may be the main targets for future research, early intervention can delay the further development of cognitive impairment in T2DM patients and improve their quality of life, which also provided early biomarkers for clarifying the mechanism of cognitive impairment in T2DM.

Sex differences in the human brain related to visual motion perception.

Previous studies have found that the temporal duration required for males to perceive visual motion direction is significantly shorter than that for females. However, the neural correlates of such shortened duration perception remain yet unclear. Given that motion perception is primarily associated with the neural activity of the middle temporal visual complex (MT+), we here test the novel hypothesis that the neural mechanism of these behavioral sex differences is mainly related to the MT+ region. We utilized ultra-high field (UHF) MRI to investigate sex differences in the MT+ brain region. A total of 95 subjects (48 females) participated in two separate studies. Cohort 1, consisting of 33 subjects (16 females), completed task-fMRI (drafting grating stimuli) experiment. Cohort 2, comprising 62 subjects (32 females), engaged in a psychophysical experiment measuring motion perception along different temporal thresholds as well as conducting structural and functional MRI scanning of MT+. Our findings show pronounced sex differences in major brain parameters within the left MT+ (but not the right MT+, i.e., laterality). In particular, males demonstrate (i) larger gray matter volume (GMV) and higher brain's spontaneous activity at the fastest infra-slow frequency band in the left MT+; and (ii) stronger functional connectivity between the left MT+ and the left centromedial amygdala (CM). Meanwhile, both female and male participants exhibited comparable correlations between motion perception ability and the multimodal imaging indexes of the MT+ region, i.e., larger GMV, higher brain's spontaneous activity, and faster motion discrimination. Our findings reveal sex differences of imaging indicators of structure and function in the MT+ region, which also relate to the temporal threshold of motion discrimination. Overall, these results show how behavioral sex differences in visual motion perception are generated, and advocate considering sex as a crucial biological variable in both human brain and behavioral research.

Cytokines and Madness: A Unifying Hypothesis of Schizophrenia Involving Interleukin-22

Schizophrenia is a severe neuropsychiatric illness of uncertain etiopathogenesis in which antipsychotic drugs can attenuate the symptoms, but patients rarely return to the premorbid level of functioning. In fact, with each relapse, people living with schizophrenia progress toward disability and cognitive impairment. Moreover, our patients desire to live normal lives, to manage their daily affairs independently, date, get married, and raise and support a family. Those of us who work daily with schizophrenia patients know that these objectives are rarely met despite the novel and allegedly improved dopamine blockers. We hypothesize that poor outcomes in schizophrenia reflect the gray matter volume reduction, which continues despite antipsychotic treatment. We hypothesize further that increased gut barrier permeability, due to dysfunctional aryl hydrocarbon receptor (AhR), downregulates the gut barrier protectors, brain-derived neurotrophic factor (BDNF), and interleukin-22 (IL-22), facilitating microbial translocation into the systemic circulation, eventually reaching the brain. Recombinant human IL-22 could ameliorate the outcome of schizophrenia by limiting bacterial translocation and by initiating tissue repair. This short review examines the signal transducer and transcription-three (STAT3)/AhR axis and downregulation of IL-22 and BDNF with subsequent increase in gut barrier permeability. Based on the hypothesis presented here, we discuss alternative schizophrenia interventions, including AhR antagonists, mitochondrial transplant, membrane lipid replacement, and recombinant human IL-22.

NCOG-09. ASSOCIATIONS OF COGNITIVE FUNCTION WITH BRAIN STRUCTURE, COMT GENOTYPE, AND PSYCHOLOGICAL FACTORS IN MELANOMA PATIENTS PRIOR TO ADJUVANT IMMUNE CHECKPOINT INHIBITOR THERAPY

Abstract BACKGROUND Cancer-related cognitive impairment (CRCI) presents a significant concern in cancer patients. Yet, limited research addresses its prevalence and potential underlying risk factors in melanoma patients, including neurobiological, genetic, and psychological factors. METHODS We assessed cognitive functioning, cognitive complaints, brain gray matter (GM) properties, COMT genotype, and psychological factors (fatigue, anxiety, depression, insomnia severity, sleep difficulties, quality of life) in malignant melanoma patients (MMPs) before treatment with immune checkpoint inhibitors (ICIs) and compared with matched healthy controls (HCs). A total of 47 MMPs and 53 HCs were enrolled. Between-group differences were tested, and statistical associations between cognitive function and brain GM properties, COMT polymorphisms, and psychological factors were explored. RESULTS MMPs exhibited significantly lower levels of cognitive functioning compared with HCs across multiple cognitive tests (all p’s&amp;lt;.05), with a high prevalence of clinically significant CRCI (68.1% VS 26.4%). Analysis of GM properties revealed volumetric differences in the left cuneus between MMPs and HCs with MMPs having smaller volume compared to HCs. In MMPs but not in HCs, statistically significant associations were found between WAIS-IV Coding and right precentral cortical thickness, TMT-A and left inferior parietal cortical thickness, and BVMT-R Delayed Recall and right postcentral GM volume (all p’s&amp;lt;.01). COMT polymorphisms were associated with self-reported cognitive complaints but not with objective cognitive performance. Compared with HCs, MMPs reported higher levels of fatigue, anxiety, insomnia severity, and sleep difficulties, and lower levels of quality of life (all p’s ≤.009). Additionally, self-reported cognitive complaints in MMPs were associated with different cognitive test performances (all p’s&amp;lt;.05), fatigue (p&amp;lt;.001) and anxiety (p&amp;lt;.045). CONCLUSIONS These findings underscore the importance of comprehensive cognitive and psychological assessments in MMPs referred for adjuvant ICI therapy. Understanding the complex array of symptoms including CRCI in this population can inform tailored interventions to improve quality of life and treatment outcomes.

Neuroanatomical basis of language ability in an autism subgroup with moderate language deficits.

Children with autism spectrum disorder (ASD) are highly heterogenous in their language abilities. A number of studies have shown neural correlates of language deficits in children with ASD, but the underlying neuroanatomical foundation of early language deficits in ASD remains largely elusive. In this study, we analyzed MRI data from a cohort of Chinese children with ASD (n = 67) and typical development (TD, n = 37) aged 1.5 to 6.5 years. The ASD sample was classified into two subgroups based on the median of the language scores: ASD with moderate language deficits (ASDmoderate, n = 34) and ASD with severe language deficits (ASDsevere, n = 34). We tested the group differences in the brain volumes between TD and two ASD subgroups, and also examined the associations between cortical grey matter volume and language abilities in TD and ASD subgroups, separately. We observed significant group differences in grey matter and white matter volume, with post-hoc analyses specifically indicating significant differences between TD and ASDmoderate subgroup. Significant correlations between grey matter volume and language scores were observed exclusively within the ASDmoderate subgroup, including positive associations in the bilateral superior temporal gyrus, hippocampus, and left inferior parietal lobe, and negative correlations in the bilateral precuneus. These findings provide novel evidence for the neuroanatomical basis related to language ability in an ASD subgroup with moderate language deficits, and offer new insights into the heterogeneity of language deficits in children with ASD.

Functional connectivity in procrastination and emotion regulation

Procrastination, an irrational delay of intended action, leads to numerous adverse effects in many life domains, such as low academic performance, poor mental health, and financial distress. Previous studies have revealed a substantial negative correlation between emotional regulation and procrastination. However, the neural basis for the association between emotion regulation and procrastination remains unclear. Therefore, we employed the voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to explore the neural substrates underlying how emotion regulation is responsible for procrastination (N = 243). In line with our hypothesis, the results showed a significant negative correlation between emotion regulation ability and procrastination. Additionally, the VBM analysis showed that emotion regulation ability was positively correlated with gray matter (GM) volumes in the right dorsal-lateral prefrontal cortex (dlPFC). The mediation analysis revealed that emotion regulation ability mediated the relationship between the GM volumes of the right dlPFC and procrastination. Furthermore, the RSFC results indicated that right dlPFC-left insula functional connectivity was positively associated with emotion regulation ability. Emotion regulation ability further mediated the relationship between the right dlPFC-left insula functional connectivity and procrastination. The current findings suggest that the neural pathway related to cognitive control over aversive emotion may be responsible for the close relationship between emotion regulation and procrastination, which provides a novel perspective for explaining the tight association between emotion regulation and procrastination.

Behavioural and neuronal substrates of serious game-based computerised cognitive training in cognitive decline: randomised controlled trial.

Investigations of computerised cognitive training (CCT) show heterogeneous results in slowing age-related cognitive decline. To comprehensively evaluate the effectiveness of serious games-based CCT, integrating control conditions, neurophysiological and blood-based biomarkers, and subjective measures. In this bi-centric randomised controlled trial with parallel groups, 160 participants (mean age 71.3 years) with cognitive impairment ranging from subjective decline to mild cognitive impairment, were pseudo-randomised to three arms: an intervention group receiving CCT immediately, an active control (watching documentaries) and a waitlist condition, which both started the CCT intervention after the control period. Both active arms entailed a 3-month intervention period comprising a total of 60 at-home sessions (five per week) and weekly on-site group meetings. In the intervention group, this was followed by additional 6 months of CCT, with monthly booster sessions to assess long-term training effects. Behavioural and subjective changes were assessed in 3-month intervals. Biological effects were measured by amyloid blood markers and magnetic resonance imaging obtained before and after training. Adherence to the training protocol was consistently high across groups and time points (4.87 sessions per week). Domain-specific cognitive scores showed no significant interaction between groups and time points. Significant cognitive and subjective improvements were observed after long-term training. Voxel-based morphometry revealed no significant changes in grey matter volume following CCT, nor did amyloid levels moderate its effectiveness. Our study demonstrates no benefits of 3 months of CCT on cognitive or biological outcomes. However, positive effects were observed subjectively and after long-term CCT, warranting the inclusion of CCT in multicomponent interventions.

The temporal relation of physical function with cognition and the influence of brain health in the oldest-old.

Introduction Physical function and cognition seem to be interrelated, especially in the oldest-old. However, the temporal order in which they are related and the role of brain health remain uncertain. Methods We included 338 participants (mean age 93.1 years) from two longitudinal cohorts: The UCI 90+ Study and EMIF-AD 90+ Study. We tested the association between physical function (Short Physical Performance Battery, gait speed and handgrip strength) at baseline with cognitive decline (MMSE, memory tests, Animal fluency, Trail Making Test (TMT) A and Digit Span Backward), and the association between cognition at baseline with physical decline (mean follow-up 3.3 years). We also tested whether measures for brain health (hippocampal, white matter lesion and gray matter volume) were related to physical function and cognition, and whether brain health was a common driver of the association between physical function and cognition by adding it as confounder (if applicable). Results Better performance on all physical tests at baseline was associated with less decline on MMSE, memory and TMT A. Conversely, fewer associations were significant but better scores on memory, TMT A and Digit Span Backward were associated with less physical decline. When adding measures for brain health as confounder, all associations stayed significant except for memory with gait speed decline. Discussion In the oldest-old, physical function and cognition are strongly related, independently of brain health. Also, the association between physical function and cognitive decline is more pronounced than the other way around, suggesting a potential for slowing cognitive decline by optimizing physical function.

Distinct brain and neurocognitive transformations after bariatric surgery: a pilot study

BackgroundObese patients have worse outcomes after surgery and are at increased risk for perioperative neurocognitive disorders (PND). Our aim was to detail the cognitive trajectories of patients undergoing bariatric surgery (BS) and map distinct structural brain changes using magnetic resonance imaging (MRI) to better understand the association between the vulnerable brain, surgery, and the arc of PND.MethodsProspective pilot study with longitudinal comprehensive cognitive assessments and MRI were performed on obese patients scheduled for BS. We analyzed baseline cognitive function and high-resolution T1-/T2-weighted brain images on 19 obese patients [age, 54 (9) years, BMI, 40 (36, 42) kg m−2] and compared with 50 healthy control subjects [age, 52 (6) years; BMI, 25 (24, 27) kg m−2]. Patients were evaluated within five days of BS (baseline), immediately after (within 48h), and follow up at six months.ResultsAt baseline, obese patients had significant brain tissue changes seen in MRI and decreased cognitive scores compared to controls (MoCA 26 vs 28, P = 0.017). Surgery induced further gray matter volume and brain tissue changes along with reduced cognitive scores within the immediate postoperative period (MoCA 26 vs 24, P &amp;lt; 0.001). At six months, we observed reversal of brain alterations for most patients and a concomitant rebound of cognitive scores to patient’s baseline status.ConclusionsBariatric surgery resulted in worsening of preexisting brain structural integrity and lower cognitive function for obese patients compared to baseline. These distinct brain lesions are consistent with specific domains of cognition. Most of these changes reverted to patient’s baseline condition within six months after surgery.

Brain-based correlates of depression and traumatic brain injury: a systematic review of structural and functional magnetic resonance imaging studies

IntroductionDepression is prevalent after traumatic brain injury (TBI). However, there is a lack of understanding of the brain-based correlates of depression post-TBI. This systematic review aimed to synthesize findings of structural and functional magnetic resonance imaging (MRI) studies to identify consistently reported neural correlates of depression post-TBI.MethodsA search for relevant published studies was conducted through OVID (MEDLINE, APA PsycINFO, and Embase), with an end date of August 3rd, 2023. Fourteen published studies were included in this review.ResultsTBI patients with depression exhibited distinct changes in diffusion- based white matter fractional anisotropy, with the direction of change depending on the acuteness or chronicity of TBI. Decreased functional connectivity (FC) of the salience and default mode networks was prominent alongside the decreased volume of gray matter within the insular, dorsomedial prefrontal, and ventromedial prefrontal cortices. Seven studies reported the correlation between observed neuroimaging and depression outcomes. Of these studies, 42% indicated that FC of the bilateral medial temporal lobe subregions was correlated with depression outcomes in TBI.DiscussionThis systematic review summarizes existing neuroimaging evidence and reports brain regions that can be leveraged as potential treatment targets in future studies examining depression post-TBI.