scholarly journals State-Independent and -Dependent Structural Connectivity Alterations in Depression

2020 ◽  
Vol 11 ◽  
Author(s):  
Yiming Fan ◽  
Jin Liu ◽  
Ling-Li Zeng ◽  
Qiangli Dong ◽  
Jianpo Su ◽  
...  

Some brain abnormalities persist at the remission phase, that is, the state-independent abnormalities, which may be one of the reasons for the high recurrence of major depressive disorder (MDD). Hence, it is of great significance to identify state-independent abnormalities of MDD through longitudinal investigation. Ninety-nine MDD patients and 118 healthy controls (HCs) received diffusion tensor imaging scanning at baseline. After 6-month antidepressant treatment, 68 patients received a second scan, among which 59 patients achieved full clinical remission. Differences in whole-brain structural connectivity (SC) between patients with MDD at baseline and HCs were estimated by two-sample t-tests. Masked with significantly changed SCs in MDD, two-sample t-tests were conducted between the remitted MDD subgroup at follow-up and HCs, and paired t-tests were implemented to compare the differences of SC in the remitted MDD subgroup before and after treatment. Significantly decreased SC between the right insula and the anterior temporal cortex (ATC), between the right ATC and the posterior temporal cortex (PTC), between the left ATC and the auditory cortex as well as increased connectivity between the right posterior cingulate cortex (PCC) and the left medial parietal cortex (MPC) were observed in the MDD group compared with the HC group at baseline (p < 0.05, FDR corrected). The decreased connectivity between the right insula and the ATC and increased connectivity between the right PCC and the left MPC persisted in the remitted MDD subgroup at follow-up (p < 0.05, FDR corrected). The decreased SC between the right insula and the ATC and increased SC between the right PCC and left MPC showed state-independent characters, which may be implicated in the sustained negative attention bias and motor retardation in MDD. In contrast, the decreased SC between the right ATC and the PTC and between the left ATC and the auditory cortex seemed to be state-dependent.

2013 ◽  
Vol 6 (2) ◽  
pp. 125-130
Author(s):  
Danelina E. Vacheva ◽  
Verjinia K. Simeonova ◽  
Boyko St. Stamenov

Summary Bulgaria ranks first in the world in incidence, morbidity and death associated with cerebrovascular disease. The aim of the study was to investigate, follow-up and register recovery of activities of daily living (using the toilet and maintaining personal hygiene) in patients with sequelae from cerebrovascular disease in a subacute stage, who underwent physiotherapy and rehabilitation. Sixty-one patients were included and followed up. They were given tailored physiotherapy and rehabilitation. This included kinesitherapy, occupational therapy and electrotherapy. All the patients filled in self-assessment questionnaires before and after the rehabilitation course. Major parameters were assessed, irrespective of the limb affected -dominant or non-dominant. Results were analyzed using the Wilcoxon rank test. At the end of the rehabilitation course, the Wilcoxon curves were driven to the right, confirming improvement concerning independence, irrespective of involvement of dominant or non-dominant limb.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Fang-Chi Hsiao ◽  
Hung-Ta Chen ◽  
Kuan-Jen Chen ◽  
Yi-Jen Hsueh ◽  
Yaa-Jyuhn James Meir ◽  
...  

Abstract Background Generally, the loss rate of human endothelial cells (HCEC) in routine cataract surgery is 8.5%. When the corneal endothelial cells density (ECD) drops, the HCEC may decompensate to keep cornea dehydration which leads to corneal edema. Granulomatosis with polyangiitis (GPA) is an uncommon autoimmune disease involving multiple organs including eyes such as conjunctivitis, scleritis, uveitis, and corneal ulcer. In this study, we report two cases of GPA whose corneal ECD decreased significantly after phacoemulsification cataract surgery. Case presentation In the first case of 69-year-old male with GPA, the ECD dropped 39.6% (OD) four months after phacoemulsification and 38.1% (OS) six months postoperatively respectively. At the final follow-up, the residual ECD was only 55% in the right eye in the 49th month, and 56% remained in the left eye in the 39th month. In the second case of 54-year old female, left ECD dropped 63.9% at the 4th month after surgery and 69.6% ECD remained at the 15th month postoperatively while similar ECD of right eye before and after left eye surgery. Conclusion Extensive preoperative ophthalmic evaluation and meticulous postoperative inflammation control should be applied to prevent severe loss of HCEC in GPA patients.


2017 ◽  
Vol 29 (7) ◽  
pp. 1239-1252 ◽  
Author(s):  
Olympia Colizoli ◽  
Jaap M. J. Murre ◽  
H. Steven Scholte ◽  
Romke Rouw

Perception is inherently subjective, and individual differences in phenomenology are well illustrated by the phenomenon of synesthesia (highly specific, consistent, and automatic cross-modal experiences, in which the external stimulus corresponding to the additional sensation is absent). It is unknown why some people develop synesthesia and others do not. In the current study, we tested whether neural markers related to having synesthesia in the family were evident in brain function and structure. Relatives of synesthetes (who did not have any type of synesthesia themselves) and matched controls read specially prepared books with colored letters for several weeks and were scanned before and after reading using magnetic resonance imaging. Effects of acquired letter–color associations were evident in brain activation. Training-related activation (while viewing black letters) in the right angular gyrus of the parietal lobe was directly related to the strength of the learned letter–color associations (behavioral Stroop effect). Within this obtained angular gyrus ROI, the familial trait of synesthesia related to brain activation differences while participants viewed both black and colored letters. Finally, we compared brain structure using voxel-based morphometry and diffusion tensor imaging to test for group differences and training effects. One cluster in the left superior parietal lobe had significantly more coherent white matter in the relatives compared with controls. No evidence for experience-dependent plasticity was obtained. For the first time, we present evidence suggesting that the (nonsynesthete) relatives of grapheme–color synesthetes show atypical grapheme processing as well as increased brain connectivity.


2021 ◽  
Author(s):  
Zhenzhen Jia ◽  
Guanya Li ◽  
Yang Hu ◽  
Hao Li ◽  
Wenchao Zhang ◽  
...  

Abstract Functional constipation (FCon) is one of the common functional gastrointestinal disorders (FGID). Previous studies reported alterations in cortical morphometry as well as changes in white matter (WM) fiber tracts and thalamo-limbic/parietal structural connectivity (SC). However, whether patients with FCon are implicated in changes in gray matter (GM) volume and associated SC remains unclear. Voxel-based morphometry (VBM) was first employed to examine differences in GM volume between 48 patients with FCon and 52 healthy controls (HC). Diffusion tensor imaging (DTI) with probabilistic tractography analysis was then employed to explore alterations in SC of these regions. Compared with the HC, patients with FCon showed decreased GM volumes in the right middle frontal gyrus (MFG_R), left insula (INS_L), and anterior cingulate cortex (ACC, PFWE < 0.05) which had a negative correlation with abdominal symptoms and difficulty of defecation respectively. Seed-based SC showed patients with FCon had decreased fractional anisotropy (FA) of bilateral INS-ACC, bilateral ACC-MFG, bilateral INS-MFG, increased axial diffusivity (AD) of bilateral ACC-MFG, and decreased radial diffusivity (RD) of bilateral INS-ACC, bilateral ACC-MFG tracts. FA of the right INS-ACC tract had a negative correlation with difficulty of defecation and AD of the ACC-left MFG tract had a negative correlation with stool symptoms. These findings reflect patients with FCon are implicated in changes in GM volumes and corresponding SC in brain regions within the salience network.


2021 ◽  
Author(s):  
Armin Attar ◽  
Fatemeh Azizi ◽  
Firoozeh Abtahi ◽  
Mojtaba Karimi

Abstract Background Anthracycline agents are routinely used for treatment of many types of malignancy, while imposing the risk for cardiotoxicity (AT-CMP). Although the right ventricle (RV) is more susceptible to cardiotoxicity, most of the studies have focused on left ventricle (LV) function for monitoring AT-CMP. In this study, we have focused on RV function before and after chemotherapy using two-dimensional speckle tracking Echocardiography (2D-STE). Material and Methods In this prospective study, newly diagnosed and untreated cancerous patients without previous cardiovascular diseases were enrolled. For all patients, baseline echocardiography was performed before the initiation of the anthracycline regimen and after 6 months of follow up when the chemotherapy was stopped. Several parameters of LV and RV function were measured using 3D echocardiography and STE techniques. Results 60 patients were enrolled in the study. There was a significant decrease (P = 0.001) in RV fractional area change (53.57 %±4.36 vs. 45.66% ±6.19), RV Global longitudinal strain (GLS) (− 22.93%±1.95 vs. −18.53 ± 2.75), and RV free wall strain (FWLS) (− 25.75%±3.01 VS. −20.30 ± 3.78). There was a significant decline in LVEF (59.42 ± 6.36% vs. 51.1 ± 6.31%) and LV-GLS (-21.1 ± 1.8% vs -18.6 ± 2.6%) (both P = 0.001) as well. Among the parameters changed following chemotherapy, RV-FWLS was dropped to a pathological level in 25% of patients showing the highest potential for detection of anthracyclines effect on the myocardium. Conclusion Anthracycline therapy can induce subclinical RV dysfunction. RV-FWLS may be proposed as the most sensitive echocardiographic marker for monitoring AT-CMP. This finding needs to be confirmed in future and larger studies.


2019 ◽  
Vol 37 (02) ◽  
pp. 137-145
Author(s):  
Stephanie L. Merhar ◽  
Elveda Gozdas ◽  
Jean A. Tkach ◽  
Nehal A. Parikh ◽  
Beth M. Kline-Fath ◽  
...  

Objective The accuracy of structural magnetic resonance imaging (MRI) to predict later cerebral palsy (CP) in newborns with perinatal brain injury is variable. Diffusion tensor imaging (DTI) and task-based functional MRI (fMRI) show promise as predictive tools. We hypothesized that infants who later developed CP would have reduced structural and functional connectivity as compared with those without CP. Study Design We performed DTI and fMRI using a passive motor task at 40 to 48 weeks' postmenstrual age in 12 infants with perinatal brain injury. CP was diagnosed at age 2 using a standardized examination. Results Five infants had CP at 2 years of age, and seven did not have CP. Tract-based spatial statistics showed a widespread reduction of fractional anisotropy (FA) in almost all white matter tracts in the CP group. Using the median FA value in the corticospinal tracts as a cutoff, FA was 100% sensitive and 86% specific to predict CP compared with a sensitivity of 60 to 80% and a specificity of 71% for structural MRI. During fMRI, the CP group had reduced functional connectivity from the right supplemental motor area as compared with the non-CP group. Conclusion DTI and fMRI obtained soon after birth are potential biomarkers to predict CP in newborns with perinatal brain injury.


Author(s):  
Shuo Zhao ◽  
Gongshu Wang ◽  
Ting Yan ◽  
Jie Xiang ◽  
Xuexue Yu ◽  
...  

Abstract Structural and functional differences between the brains of female and male adults have been well documented. However, potential sex differences in the patterns of rich-club organization and the coupling between their structural connectivity (SC) and functional connectivity (FC) remain to be determined. In this study, functional magnetic resonance imaging and diffusion tensor imaging techniques were combined to examine sex differences in rich-club organization. Females had a stronger SC-FC coupling than males. Moreover, stronger SC-FC coupling in the females was primarily located in feeder connections and non–rich-club nodes of the left inferior frontal gyrus and inferior parietal lobe and the right superior frontal gyrus and superior parietal gyrus, whereas higher coupling strength in males was primarily located in rich-club connections and rich-club node of the right insula, and non-rich-club nodes of the left hippocampus and the right parahippocampal gyrus. Sex-specific patterns in correlations were also shown between SC-FC coupling and cognitive function, including working memory and reasoning ability. The topological changes in rich-club organization provide novel insight into sex-specific effects on white matter connections that underlie a potential network mechanism of sex-based differences in cognitive function.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
A. Van de Winckel ◽  
D. De Patre ◽  
M. Rigoni ◽  
M. Fiecas ◽  
T. J. Hendrickson ◽  
...  

AbstractCognitive Multisensory Rehabilitation (CMR) is a promising therapy for upper limb recovery in stroke, but the brain mechanisms are unknown. We previously demonstrated that the parietal operculum (parts OP1/OP4) is activated with CMR exercises. In this exploratory study, we assessed the baseline difference between OP1/OP4 functional connectivity (FC) at rest in stroke versus healthy adults to then explore whether CMR affects OP1/OP4 connectivity and sensorimotor recovery after stroke. We recruited 8 adults with chronic stroke and left hemiplegia/paresis and 22 healthy adults. Resting-state FC with the OP1/OP4 region-of-interest in the affected hemisphere was analysed before and after 6 weeks of CMR. We evaluated sensorimotor function and activities of daily life pre- and post-CMR, and at 1-year post-CMR. At baseline, we found decreased FC between the right OP1/OP4 and 34 areas distributed across all lobes in stroke versus healthy adults. After CMR, only four areas had decreased FC compared to healthy adults. Compared to baseline (pre-CMR), participants improved on motor function (MESUPES arm p = 0.02; MESUPES hand p = 0.03; MESUPES total score p = 0.006); on stereognosis (p = 0.03); and on the Frenchay Activities Index (p = 0.03) at post-CMR and at 1-year follow-up. These results suggest enhanced sensorimotor recovery post-stroke after CMR. Our results justify larger-scale studies.


2011 ◽  
Vol 91 (4) ◽  
pp. 1357-1392 ◽  
Author(s):  
Angela D. Friederici

Language processing is a trait of human species. The knowledge about its neurobiological basis has been increased considerably over the past decades. Different brain regions in the left and right hemisphere have been identified to support particular language functions. Networks involving the temporal cortex and the inferior frontal cortex with a clear left lateralization were shown to support syntactic processes, whereas less lateralized temporo-frontal networks subserve semantic processes. These networks have been substantiated both by functional as well as by structural connectivity data. Electrophysiological measures indicate that within these networks syntactic processes of local structure building precede the assignment of grammatical and semantic relations in a sentence. Suprasegmental prosodic information overtly available in the acoustic language input is processed predominantly in a temporo-frontal network in the right hemisphere associated with a clear electrophysiological marker. Studies with patients suffering from lesions in the corpus callosum reveal that the posterior portion of this structure plays a crucial role in the interaction of syntactic and prosodic information during language processing.


2008 ◽  
Vol 20 (2) ◽  
pp. 268-284 ◽  
Author(s):  
Cibu Thomas ◽  
Linda Moya ◽  
Galia Avidan ◽  
Kate Humphreys ◽  
Kwan Jin Jung ◽  
...  

An age-related decline in face processing, even under conditions in which learning and memory are not implicated, has been well documented, but the mechanism underlying this perceptual alteration remains unknown. Here, we examine whether this behavioral change may be accounted for by a reduction in white matter connectivity with age. To this end, we acquired diffusion tensor imaging data from 28 individuals aged 18 to 86 years and quantified the number of fibers, voxels, and fractional anisotropy of the two major tracts that pass through the fusiform gyrus, the pre-eminent face processing region in the ventral temporal cortex. We also measured the ability of a subset of these individuals to make fine-grained discriminations between pairs of faces and between pairs of cars. There was a significant reduction in the structural integrity of the inferior fronto-occipital fasciculus (IFOF) in the right hemisphere as a function of age on all dependent measures and there were also some changes in the left hemisphere, albeit to a lesser extent. There was also a clear age-related decrement in accuracy of perceptual discrimination, especially for more challenging perceptual discriminations, and this held to a greater degree for faces than for cars. Of greatest relevance, there was a robust association between the reduction of IFOF integrity in the right hemisphere and the decline in face perception, suggesting that the alteration in structural connectivity between the right ventral temporal and frontal cortices may account for the age-related difficulties in face processing.


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