Brain Imaging and Behavior最新文献

Sex differences in static structure-function coupling between structural connectivity (SC) and functional connectivity (FC) have been documented. However, the human brain is highly dynamic, and static coupling fails to capture the time-varying properties of neural activity. It remains unclear how sex influences dynamic SC-FC coupling over time. Moreover, intrinsic functional networks represent a core feature of brain organization. Here, we quantified sex differences in dynamic FC strength and SC-FC coupling at the intrinsic functional network level using a sliding window approach. Using two window sizes (50 TRs and 30 TRs), we constructed dynamic FC networks and identified hyper-connected and hypo-connected states via k-means clustering. The results showed females performed higher whole-brain SC-FC coupling in hyper-connected state. Specifically, females exhibited higher FC strength and coupling in systems related default mode network in this state. In addition, females exhibited higher FC strength and coupling in systems related limbic/paralimbic and subcortical network in hypo-connected state. Males exhibited higher FC strength and coupling in systems related somatosensory/motor and auditory network in hyper-connected state. Finally, sex-specific patterns in correlations were shown between SC-FC coupling and cognitive performance in distinct states. This study provides new insights into sex-related effects on the neurodevelopmental basis of cognitive function through the perspective of dynamic SC-FC coupling.

Perinatal strokes occur more commonly in the left hemisphere and often impact language areas, yet language disability only occurs in a small proportion of cases. Functional imaging studies investigating language processing have shown that perinatal stroke in the left hemisphere may result in contralesional shifts of activity, but none have investigated the structure of white matter connections in such altered language network conditions. Diffusion tensor imaging and neurite orientation dispersion and density imaging offer robust, microstructurally-sensitive metrics which can richly characterize tracts known to support language function. In a sample of 105 participants aged 6 to 19, 73 participants with perinatal stroke and 32 typically-developing controls, we applied these techniques to evaluate differences in microstructure of the arcuate fasciculus and uncinate fasciculus, two tracts classically associated with language, following perinatal stroke while controlling for age, sex, and lesion volume. We identified widespread differences in microstructure in both hemispheres for the arcuate and uncinate fasciculi in perinatal stroke participants compared to controls. Subtypes of perinatal stroke presented differently, with arterial ischemic stroke lesions showing more structural differences than periventricular infarction lesions. Differences between perinatal stroke subtypes were observed for both tracts in both hemispheres. Overall, we demonstrate that white matter microstructure of bilateral language networks is impacted by unilateral perinatal stroke. These bilateral differences in white matter structure after unilateral injury suggest that neuroplastic mechanisms may operate in both hemispheres during development with possible functional implications that could inform customized patient-centered rehabilitation strategies.

Multiple studies point to the role of neuroinflammation in the pathophysiology of schizophrenia (SCZ), however, there have been few in vivo tools for imaging brain inflammation. Diffusion basis spectrum imaging (DBSI) is an advanced diffusion-based MRI method developed to quantitatively assess microstructural alternations relating to neuroinflammation, axonal fiber, and other white matter (WM) pathologies. We acquired one-hour-long high-directional diffusion MRI data from young control (CON, n = 27), schizophrenia (SCZ, n = 21), and bipolar disorder (BPD, n = 21) participants aged 18-30. We applied Tract-based Spatial Statistics (TBSS) to allow whole-brain WM analyses and compare DBSI-derived isotropic and anisotropic diffusion measures between groups. Clinical relationships of DBSI metrics with clinical symptoms were assessed across SCZ and control participants. In SCZ participants, we found a generalized increase in DBSI-derived cellularity (a putative marker of neuroinflammation), a decrease in restricted fiber fraction (a putative marker of apparent axonal density), and an increase in extra-axonal water (a putative marker of vasogenic edema) across several WM tracts. There were only minimal WM abnormalities noted in BPD, mainly in regions of the corpus callosum (increase in DTI-derived RD and extra-axonal water). DBSI metrics showed significant partial correlations with psychosis and mood symptoms across groups. Our findings suggest that SCZ involves generalized white matter neuroinflammation, decreased fiber density, and demyelination, which is not seen in bipolar disorder. Larger studies are needed to identify medication-related effects. DBSI metrics could help identify high-risk groups requiring early interventions to prevent the onset of psychosis and improve outcomes.

Emotion regulation is a vital life skill, and cognitive reappraisal (CR) is the most effective emotion regulation strategy, which plays a key role in healthy aging. In memory clinic patients, problems with emotion regulation difficulties and cognitive impairment are very common, often accompanied by signs of cerebral small vessel disease (CSVD) on their magnetic resonance imaging (MRI). Is there a correlation among cognitive reappraisal failure, cognitive impairment, and CSVD in these older adults? This study aims to investigate the question. A standardized emotion regulation task was used to measure CR ability. A total of 170 older adults were included in statistical analysis, of which 78 were considered as cognitive reappraisal failure (CR-Failure). All participants completed the emotion regulation task, neuropsychiatric assessments, and MRI scans, with traditional CSVD markers being evaluated. Our analysis indicated that CR ability is negatively correlated with scores on the Hamilton Depression Rating Scale and the Hamilton Anxiety Rating Scale. Additionally, logical memory and executive function are significant factors in CR utilization. A higher burden of CSVD or presence of cognitive impairment is an independent risk factor for cognitive reappraisal failure in memory clinic older adults. Furthermore, cognitive impairment significantly mediates the relationship between greater CSVD burden and CR failure.

The aim of this study is to investigate the disparities in volumes of hippocampal subfields and alterations in whole-brain functional connectivity among individuals diagnosed with diabetic retinopathy (DR). This study comprised a total of 32 diabetic patients with retinopathy (DR group, n = 32) and 38 healthy adults (HC group, n = 38), who underwent psychological cognitive testing along with structural and functional magnetic resonance imaging. The FreeSurfer software was utilized for the extraction and computation of hippocampal subfield volumes, as well as the overall volumes of the left and right hippocampus. The volumetric comparisons were conducted by employing independent sample t-tests in SPSS 26.0. The functional connectivity comparisons were subjected to statistical analysis using the Matlab software. Age, education level and grnder were used as control variables, and partial correlation analysis was performed to investigate the relationship between differences in volume and functional connectivity values with psychological cognitive test results and clinical indicators. The volume of the left hippocampal tail and fissure, as well as the right hippocampal C3, C4 and fissure regions in the DR patient group, exhibited significant differences compared to the HC group (P < 0.05, FDR < 0.05). Regions of interest were identified based on the segmented volume differences, and compared to the HC group, enhanced connectivity was observed between the left hippocampal tail and the left caudate nucleus (MNI: x,y, z=-6, 12, 9) and the right caudate nucleus (MNI: x,y, z = 9, 12, 12) in DR patients. Additionally, reduced connectivity was observed between the left hippocampal fissure and the right precentral gyrus (MNI: x, y, z = 57, 0, 45) and the right supplementary motor area (MNI: x, y, z = 9, 3, 60). Partial correlation analysis, with age, education level, and gender as covariates, showed no significant associations between the imaging changes and clinical indicators or cognitive scores. The alterations in hippocampal volume and function observed in patients with DR may potentially underlie their cognitive impairment and sensorimotor deficits, thus suggesting a plausible neuropathological mechanism.

To investigate the grey matter volume (GMV) changes and uremic metabolites in end-stage kidney disease (ESKD) patients with mild cognitive impairment (MCI) (ESKD-MCI) and further examine the classification and diagnostic efficacy of these features for ESKD-MCI patients. A total of 65 patients with ESKD, including 34 ESKD-MCI and 31 with non-cognitive impairment (ESKD-NCI), and 55 health controls (HCs) were enrolled. All participants underwent brain structural magnetic resonance imaging (MRI) scanning and Montreal cognitive assessment test. Clinical characteristics and GMV differences among these three groups were analyzed. In addition, mediation analysis was performed to determine the mediating effect of GMV changes on the association between clinical risk factors and MCI. Finally, support vector machine were employed to examine the classification and diagnostic efficacy of GMV changes and clinical features for MCI. Both patient groups exhibited widespread structural brain injury compared with the HCs. Moreover, compared with ESKD-NCI, ESKD-MCI patients demonstrated reduced GMV specifically in the left middle temporal gyrus and inferior temporal gyrus. Notably, these GMV changes completely mediates the effect of serum phosphorus levels on MCI. Furthermore, imaging features rather than serum phosphorus levels had good classification and diagnostic efficacy for ESKD-MCI. Our findings underscore the significance of the left temporal gyrus as a pivotal brain region in ESKD-MCI patients, fully mediating the link between uremic metabolite and MCI. GMV alterations presents a promising avenue for effectively detecting MCI in individuals with ESKD.

Cognitive decline is a common non-motor symptom of Parkinson's disease (PD), which can occur at any stage of the disease. However, the neural mechanisms of PD cognitive changes remain unclear. It has been reported that hemispheric asymmetry is associated with cognitive impairment. Thus, we aimed to explore the underlying mechanisms of PD subgroups with different degrees of cognitive progression by assessing functional interhemispheric coordination and their relations with cognition. Fifty-four PD patients including 29 stable cognitive performance (sPD) patients, 25 progressive cognitive impairment (pPD) patients, and 18 healthy controls (HC) were recruited in this study. All subjects underwent T1-weighted, resting-state functional magnetic resonance imaging scanning, and neuropsychological evaluations. Voxel-mirrored Homotopic Connectivity (VMHC) and voxel-based morphometry analysis were applied to detect functional interhemispheric coordination. Fisher z transformed VMHC (z-VMHC) value lower in the middle temporal gyrus (MTG), middle occipital gyrus (MOG), and superior temporal gyrus (STG) in the pPD group when compared to the sPD group. However, we did not detect the difference in gray matter volume among the three groups. Furthermore, the z-VMHC value of MTG and MOG was positively correlated with the Montreal Cognitive Assessment (MoCA) score of the follow-up. Therefore, z-VMHC values within the MTG, MOG, and STG appeared to be potential neuroimaging features to distinguish pPD patients from sPD groups. These findings may underlie the neural mechanisms of cognitive performance in PD.

The pathophysiological mechanisms underlying suicidal ideation and decreased cognitive function in bipolar depression remain elusive. This study sought to elucidate the potential neuroanatomical basis of these phenomena using diffusion tensor imaging (DTI). 40 patients experiencing bipolar depressive episodes were enrolled, comprising 20 individuals with suicidal ideation (BDSI +), 20 without suicidal ideation (BDSI-), and 20 healthy controls (HCs), all of whom underwent DTI scanning. Clinical assessments primarily utilized the Beck Scale for Suicide Ideation (BSSI) and the Trail Making Test (TMT). Differences in fractional anisotropy (FA) values among the groups were compared using Tract-Based Spatial Statistics (TBSS). The identified differential brain regions were designated as regions of interest (ROIs), and covariance analysis was employed to compare the FA values among the three groups. Partial correlation analyses were conducted between the FA values in the ROIs and clinical symptoms. Differences in brain regions identified through TBSS were observed in the genu of the corpus callosum and the left anterior corona radiata (p < 0.05). Covariance analysis revealed that the BDSI + group exhibited significantly lower FA values in these regions compared to the HCs (p < 0.05). Partial correlation analyses showed that the FA values in the genu of corpus callosum were negatively correlated with BSSI scores (r = -0.592, p = 0.026) and TMT-A scores (r = -0.642, p = 0.013). The findings from this study suggest that alterations in the connectivity of the genu of the corpus callosum may relate to suicidal ideation and visuospatial function in patients with bipolar depression.

Preclinical research highlights the paraventricular thalamic nucleus as important in various stages of substance use disorder. However, there is limited research on it in relation to methamphetamine, especially regarding its functional changes after long-term abstinence. This study aims to understand the alterations in functional connectivity of the paraventricular thalamic nucleus in methamphetamine abstainers and its correlation with drug craving at two different withdrawal periods. A total of 49 subjects were allocated to the short-term withdrawal group, 44 to the long-term withdrawal group, and 42 to the healthy control group, all of whom are male and adult. Craving scores were assessed using a visual analogue scale. Functional connectivity was evaluated through resting-state functional MRI, which reflects the correlation between connectivity in different brain regions. Significant differences in functional connectivity between the paraventricular thalamic nucleus and the left caudate nucleus were observed across the three groups. The healthy control group exhibited the strongest connectivity, followed by the long-term withdrawal group, while the short-term withdrawal group demonstrated the weakest connectivity. Within the short-term withdrawal group, functional connectivity of the paraventricular thalamic nucleus with both the left parahippocampal gyrus (r = -0.45, p = 0.001) and the left inferior temporal gyrus (r = -0.43, p = 0.002) was significantly correlated with craving scores. This study confirms abnormalities in the paraventricular thalamic nucleus among male methamphetamine abstainers, emphasizes its potential role in regulating methamphetamine use disorder and craving mechanisms, and offers insights into long-term changes in brain function after abstinence.