Brain Imaging and Behavior最新文献

Although structural and functional damage to the brain is considered to be an important neurobiological mechanism of postoperative delirium (POD), alterations in the visual cortical network related to this vulnerability have not yet been determined. In this study, we investigated the impact of alterations in the visual network (VN), as measured by structural and functional magnetic resonance imaging (MRI), on the development of POD. Thirty-six adult patients with frontal glioma who underwent elective craniotomy were recruited. The primary outcome was POD 1–7 days after surgery, as assessed by the Confusion Assessment Method. Cognition before surgery was measured by a battery of neuropsychological tests. Then, we evaluated preoperative and postoperative gray matter volume (GMV) and functional connectivity (FC) alterations by voxel-based morphometry and resting-state functional MRI (rs-fMRI) between the POD and non-POD groups. Multiple logistic regression models were used to investigate the associations between neuroimaging biomarkers and the occurrence of POD. Compared to those in the non-POD group, a decreased GMV in the fusiform gyrus (0.181 [0.018] vs. 0.207 [0.022], FDRp = 0.001) and decreased FC between the fusiform gyrus and VN (0.351 [0.153] vs. 0.610 [0.197], GFRp < 0.001) were observed preoperatively in the POD group, and increased FC between the fusiform gyrus and ventral attentional network (0.538 [0.180] vs. 0.452 [0.184], GFRp = < 0.001) was observed postoperatively in the POD group. According to our multiple logistic regression analysis, age (Odds ratio [OR]: 1.141 [1.015 to 1.282], P = 0.03) and preoperative fusiform-VN FC (OR 0.001 [0.001 to 0.067], P = 0.01) were significantly related to risk of POD. Our findings suggested that preoperative functional disconnectivity between fusiform and VN might be highly involved in the development of POD. These findings may allow for the discovery of additional underlying mechanisms.

Several studies have revealed altered intrinsic neural activity in chronic insomnia (CI). However, the temporal variability of intrinsic neural activity in CI is rarely mentioned. This study aimed to explore static and temporal dynamic alterations of regional homogeneity (ReHo) in CI and excavate the potential associations between these changes and clinical characteristics. Eighty-seven patients with CI and seventy-eight healthy controls (HCs) were included. Resting-state functional magnetic resonance imaging was performed on all subjects and both static and dynamic ReHo were used to detect local functional connectivity. We then tested the relationship between altered brain regions, disease duration, and clinical scales. The receiver operating characteristic curve analysis was used to reveal the potential capability of these indicators to screen CI patients from HCs. CI showed increased dynamic ReHo in the right precuneus and decreased static ReHo in the right cerebellum_6. The dynamic ReHo values of the right precuneus were negatively correlated with the self-rating depression score and the static ReHo values of the right cerebellum_6 were positively correlated with the Montreal Cognitive Assessment-Naming score. In addition, the combination of the two metrics showed a potential capacity to distinguish CI patients from HCs, which was better than a single metric alone. The present study has revealed the altered local functional connectivity under static and temporal dynamic conditions in patients with CI, and found the relationships between these changes, mood-related scales, and cognitive-related scales. These may be useful in elucidating the neurological mechanisms of CI and accompanying symptoms.

Our study investigated the associations between the clinical benefits of telehealth-delivered cognitive behavioral therapy for insomnia (tele-CBT-I) and the salience network in fibromyalgia (FM). Thirty-five FM patients with comorbid insomnia were recruited and assigned into two groups: the tele-CBT-I group (n = 17) or the treatment-as-usual (TAU) group (n = 18). At baseline and post-treatment, clinical status was assessed using standardized scales, including the Insomnia Severity Index (ISI), Brief Pain Inventory, Numeric Pain Rating scale, Beck Depression Intervention version II, Beck Anxiety Intervention, Situational Fatigue Scale, and Fibromyalgia Impact Questionnaires. Resting-state functional magnetic resonance imaging was collected. We compared within- and between-group differences in clinical changes and functional connectivity (FC) of the salience network. A factor analysis of significant FCs was performed. Correlation analyses between clinical symptoms and salience FCs were conducted. The tele-CBT-I group showed sleep quality improvements after treatment that were greater than those in the TAU group (p-value = 0.038). After treatment, tele-CBT-I decreased FCs of cortical regions and increased FCs of subcortical regions compared to the TAU group. Additionally, factor analysis grouped the significant FCs into cortical factors and subcortical factors. The cortical factor value, representing the involvement of specific cortical regions of the salience network by the factor analysis, was significantly associated with ISI scores in the tele-CBT-I group (p-value = 0.0002). In conclusion, tele-CBT-I might be an adjuvant approach to improve sleep quality and normalize cortical and subcortical functions of the salience network in FM patients with comorbid insomnia.

Sleep disturbances (SD) are common in major depressive disorder (MDD) patients. Brain functional asymmetry is crucial for understanding MDD pathophysiology. Previous studies using the parameter of asymmetry (PAS) approach have found brain functional asymmetry disruption in MDD. However, this has not been explored in MDD patients with SD. This study examined 26 MDD patients with SD, 34 MDD patients without SD, and 34 healthy controls using resting-state functional magnetic resonance imaging scans. SD symptoms were quantified using the 17-item Hamilton Rating Scale for Depression. PAS approach was used to evaluate functional asymmetry. MDD patients with SD displayed increased PAS in the left middle frontal gyrus (MFG)/inferior frontal gyrus (IFG) and decreased PAS in the left parahippocampal gyrus (PHG) compared to MDD patients without SD. Increased PAS in the left MFG/IFG was positively correlated with SD severity, and a negative correlation was found between decreased PAS in the left PHG and SD scores in all MDD patients. Receiver operating characteristic analysis indicated that increased PAS in the left MFG/IFG and decreased PAS in the left PHG may serve as potential neuroimaging markers to differentiate MDD patients with SD from those without SD with Area Under Curve values of 0.8157 and 0.8068, respectively. These results highlighted that increased PAS in the left MFG/IFG and decreased PAS in the left PHG may be considered a prominent feature associated with SD symptoms of MDD patients, potentially serving as imaging markers to discriminate between MDD patients with and without SD.

Insomnia is a widespread health problem among adults, and it impairs cognitive control and emotional regulation functions. Stress and insomnia are positively correlated, and their vicious cycle has been widely reported. In this study, we explore the neural biomarkers of insomnia from the perspective of whole-brain functional connectivity and investigate the neural mechanisms underlying the association between stress and insomnia. The current study was conducted on a cross-sectional sample (N = 430). First, we investigated the correlation between perceived stress and insomnia. Second, we applied connectome-based predictive modeling (CPM) to determine the neuromarkers of insomnia. Finally, we explored the neural basis underlying the association between perceived stress and insomnia. A significant positive correlation was found between perceived stress and insomnia in the present research. Results of CPM revealed the following as the neural substrates supporting insomnia: the emotion regulation circuit involving repetitive negative thinking and the cognitive control circuit involving attention control. According to further results from mediation analysis, the frontoparietal network supporting cognitive emotion regulation is an important neural mechanism that maintains the correlation between stress and insomnia. The present study offers a profound insight into the alterations of brain activity related to insomnia, and it further investigates the neural underpinnings of the robust association between stress and insomnia. This study also opens new avenues for neural interventions to alleviate stress-related insomnia.

Resting-state functional connectivity (FC) is suggested to be cross-sectionally associated with both vascular burden and Alzheimer's disease (AD) pathology. For instance, studies in pre-clinical AD subjects have shown increases of cerebral spinal fluid soluble platelet-derived growth factor receptor-β (CSF sPDGFRβ, a marker of BBB breakdown) but have not demonstrated if this vascular impairment affects neuronal dysfunction. It’s possible that increased levels of sPDGFRβ in the CSF may correlate with impaired FC in metabolically demanding brain regions (i.e. Default Mode Network, DMN). Our study aimed to investigate the relationship between these two markers in older individuals that were cognitively normal and had cognitive impairment. Eighty-nine older adults without dementia from the University of Southern California were selected from a larger cohort. Region of interest (ROI) to ROI analyses were conducted using DMN seed regions. Linear regression models measured significant associations between BOLD FC strength among seed-target regions and sPDGFRβ values, while covarying for age and sex. Comparison of a composite ROI created by averaging FC values between seed and all target regions among cognitively normal and impaired individuals was also examined. Using CSF sPDGFRβ as a biomarker of BBB breakdown, we report that increased breakdown correlated with decreased functional connectivity in DMN areas, specifically the PCC, and while the hippocampus exhibited an interaction effect using CDR score, this was an exploratory analysis that we feel can lead to further research. Ultimately, we found that BBB breakdown, as measured by CSF sPDGFRβ, is associated with neural networks, and decreased functional connections.

Chronic headache (persistent or recurrent headache for 3-months or longer) is highly prevalent among youth. While sleep disturbances have been associated with headache, their inter-relationship with brain connectivity remains unknown. This observational study examined whether self-report and actigraphy measures of sleep were associated with alterations to white matter tracts (i.e., uncinate fasciculus and cingulum) in youth with chronic headache versus healthy controls. Thirty youth aged 10-18 years with chronic headache and thirty controls underwent an MRI. Diffusion tensor images were obtained and mean fractional anisotropy values of the cingulum and uncinate were extracted. One-week prior to their MRI, youth wore an actigraph to obtain sleep duration, wake after sleep onset and sleep efficiency measures. Moreover, they completed questionnaires regarding their sleep quality and pain symptomatology. Linear regression was applied to examine the relationships between sleep (self-report and actigraphy), fractional anisotropy, and number of headache days per month. Self-report and actigraphy measures of sleep did not differ between patients and controls. However, poorer self-reported sleep quality was associated with lower fractional anisotropy values in the left uncinate (P = 0.05). Lower left uncinate fractional anisotropy was related to increased headache frequency (P = 0.002) in youth with chronic headache. Therefore, alterations to connectivity may be associated with the relationship between altered perceptions of sleep and headache chronicity.

Although brain cholinergic denervation has been largely associated with cognitive decline in patients with Parkinson's disease (PD), new evidence suggests that cholinergic upregulation occurs in the hippocampus of PD patients without cognitive deficits. The specific hippocampal sectors and potential mechanisms of this cholinergic compensatory process have been further studied here, using MRI volumetry and morphometry coupled with molecular imaging using the PET radiotracer [¹⁸F]-Fluoroethoxybenzovesamicol ([¹⁸F]-FEOBV). Following a thorough screening procedure, 18 participants were selected and evenly distributed in three groups, including cognitively normal PD patients (PD-CN), PD patients with mild cognitive impairment (PD-MCI), and healthy volunteers (HV). Participants underwent a detailed neuropsychological assessment, structural MRI, and PET imaging with [¹⁸F]-FEOBV. Basal forebrain Ch1-Ch2 volumes were measured using stereotaxic mapping. Hippocampal subfields were automatically defined using the MAGeT-Brain segmentation algorithm. Cholinergic innervation density was quantified using [¹⁸F]-FEOBV uptake. Compared with HV, both PD-CN and PD-MCI displayed significantly reduced volumes in CA2-CA3 bilaterally. We found no other hippocampal subfield nor Ch1-Ch2 volume differences between the three groups. PET imaging revealed higher [¹⁸F]-FEOBV uptake in CA2-CA3 of the PD-CN compared with HV or PD-MCI. A positive correlation was observed between cognitive performances and [¹⁸F]-FEOBV uptake in the right CA2-CA3 subfield. Reduced volume, together with increased [¹⁸F]-FEOBV uptake, were observed specifically in the CA2-CA3 hippocampal subfields. However, while the volume change was observed in both PD-CN and PD-MCI, increased [¹⁸F]-FEOBV uptake was present only in the PD-CN group. This suggests that a cholinergic compensatory process takes place in the atrophied CA2-CA3 hippocampal subfields and might underlie normal cognition in PD.

Inflammatory mechanisms may play crucial roles in the pathophysiology of major depressive disorder (MDD), and cytokine concentrations are correlated with brain alterations. Adolescents and young adults with MDD have higher recurrence and suicide rates than adults, but there has been limited research on the underlying mechanisms. In this study, we aimed to investigate the potential correlations among cytokines, depression severity, and the volumes of the amygdala, hippocampus, and nucleus accumbens in Han Chinese adolescents and young adults with first-episode MDD. Nineteen patients with MDD aged 10-21 years were enrolled from the Psychiatry Department of the First Affiliated Hospital of Chongqing Medical University, along with 18 age-matched healthy controls from a local school. We measured the concentrations of interleukin (IL)-4, IL-6, IL-8, and IL-10 in the peripheral blood, along with the volumes of the amygdala, hippocampus, and nucleus accumbens, as determined by magnetic resonance imaging. We observed that patients with MDD had higher concentrations of IL-6 and a trend towards reduced left amygdala and bilateral hippocampus volumes than healthy controls. Additionally, the concentration of IL-6 was correlated with the left amygdala volume and depression severity, while the left hippocampus volume was correlated with depression severity. This study suggests that inflammation is an underlying neurobiological change and implies that IL-6 could serve as a potential biomarker for identifying early stage MDD in adolescents and young adults.

Employing functional magnetic resonance imaging (fMRI) techniques, we conducted a comprehensive analysis of neural responses during sign language, picture, and word processing tasks in a cohort of 35 deaf participants and contrasted these responses with those of 35 hearing counterparts. Our voxel-based analysis unveiled distinct patterns of brain activation during language processing tasks. Deaf individuals exhibited robust bilateral activation in the superior temporal regions during sign language processing, signifying the profound neural adaptations associated with sign comprehension. Similarly, during picture processing, the deaf cohort displayed activation in the right angular, right calcarine, right middle temporal, and left angular gyrus regions, elucidating the neural dynamics engaged in visual processing tasks. Intriguingly, during word processing, the deaf group engaged the right insula and right fusiform gyrus, suggesting compensatory mechanisms at play during linguistic tasks. Notably, the control group failed to manifest additional or distinctive regions in any of the tasks when compared to the deaf cohort, underscoring the unique neural signatures within the deaf population. Multivariate Pattern Analysis (MVPA) of functional connectivity provided a more nuanced perspective on connectivity patterns across tasks. Deaf participants exhibited significant activation in a myriad of brain regions, including bilateral planum temporale (PT), postcentral gyrus, insula, and inferior frontal regions, among others. These findings underscore the intricate neural adaptations in response to auditory deprivation. Seed-based connectivity analysis, utilizing the PT as a seed region, revealed unique connectivity pattern across tasks. These connectivity dynamics provide valuable insights into the neural interplay associated with cross-modal plasticity.