scholarly journals Morphological, Structural, and Functional Networks Highlight the Role of the Cortical-Subcortical Circuit in Individuals With Subjective Cognitive Decline

2021 ◽  
Vol 13 ◽  
Author(s):  
Xiaowen Xu ◽  
Tao Wang ◽  
Weikai Li ◽  
Hai Li ◽  
Boyan Xu ◽  
...  

Subjective cognitive decline (SCD) is considered the earliest stage of the clinical manifestations of the continuous progression of Alzheimer’s Disease (AD). Previous studies have suggested that multimodal brain networks play an important role in the early diagnosis and mechanisms underlying SCD. However, most of the previous studies focused on a single modality, and lacked correlation analysis between different modal biomarkers and brain regions. In order to further explore the specific characteristic of the multimodal brain networks in the stage of SCD, 22 individuals with SCD and 20 matched healthy controls (HCs) were recruited in the present study. We constructed the individual morphological, structural and functional brain networks based on 3D-T1 structural magnetic resonance imaging (sMRI), diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI), respectively. A t-test was used to select the connections with significant difference, and a multi-kernel support vector machine (MK-SVM) was applied to combine the selected multimodal connections to distinguish SCD from HCs. Moreover, we further identified the consensus connections of brain networks as the most discriminative features to explore the pathological mechanisms and potential biomarkers associated with SCD. Our results shown that the combination of three modal connections using MK-SVM achieved the best classification performance, with an accuracy of 92.68%, sensitivity of 95.00%, and specificity of 90.48%. Furthermore, the consensus connections and hub nodes based on the morphological, structural, and functional networks identified in our study exhibited abnormal cortical-subcortical connections in individuals with SCD. In addition, the functional networks presented more discriminative connections and hubs in the cortical-subcortical regions, and were found to perform better in distinguishing SCD from HCs. Therefore, our findings highlight the role of the cortical-subcortical circuit in individuals with SCD from the perspective of a multimodal brain network, providing potential biomarkers for the diagnosis and prediction of the preclinical stage of AD.

2015 ◽  
Vol 36 (4) ◽  
pp. 808-818 ◽  
Author(s):  
Ting-Yu Chang ◽  
Kuo-Lun Huang ◽  
Meng-Yang Ho ◽  
Pei-Shan Ho ◽  
Chien-Hung Chang ◽  
...  

Significant carotid stenosis compromises hemodynamics and impairs cognitive functions. The interplay between these changes and brain connectivity has rarely been investigated. We aimed to discover the changes of functional connectivity and its relation to cognitive decline in carotid stenosis patients. Twenty-seven patients with unilateral carotid stenosis (≥60%) and 20 age- and sex-matched controls underwent neuropsychological tests and resting-state functional magnetic resonance imaging. The patients also received perfusion magnetic resonance imaging. The relationships between cognitive function and functional networks among the patients and controls were evaluated. Graph theory was applied on resting-state functional magnetic resonance imaging network analysis, which revealed that the hemispheres ipsilateral to the stenosis were significantly impaired in “degree” and “global efficiency.” The neuropsychological performances were positively correlated with degree, clustering coefficient, local efficiency, and global efficiency, and negatively correlated with characteristic path length, modularity, and small-worldness in the patients, whereas these relationships were not observed in the controls. In this study, we identified the networks that were impaired in the affected hemispheres in patients with carotid stenosis. Specific indices (global efficiency, characteristic path length, and modularity) were highly correlated with neuropsychological performance in our patients. Analysis of brain connectivity may help to elucidate the relationship between hemodynamic impairment and cognitive decline.


2021 ◽  
Author(s):  
Federica Ribaldi ◽  
Christian Chicherio ◽  
Daniele Altomare ◽  
Marta Martins ◽  
Szymon Tomczyk ◽  
...  

Abstract BACKGROUND. Subjective cognitive decline (SCD) is the subjective perception of a decline in memory and/or other cognitive functions in the absence of objective evidence. Some SCD individuals however may suffer from very early stages of neurodegenerative diseases (such as Alzheimer’s disease, AD), minor psychiatric conditions, neurological, and/or somatic comorbidities. Even if a theoretical framework has been established, the etiology of SCD remains far from elucidated. Clinical observations recently lead to the hypothesis that patients with incipient AD may have overestimated metacognitive judgements of their own cognitive performance, while psychiatric patients typically present underestimated metacognitive judgements. Moreover, brain connectivity changes are known correlates of AD and psychiatric conditions, and might be used as biomarkers to discriminate SCD patients of different etiologies. The aim of the COSCODE study is to identify metacognition, connectivity, behavioural, and biomarker profiles associated with different etiologies of SCD. Here we present its rationale and study design.METHODS. COSCODE is an observational, longitudinal (4 years), prospective clinical cohort study involving 120 SCD, and 80 control subjects (40 persons with no cognitive impairment, and 40 mild cognitive impairment - MCI, or dementia patients), all of which will undergo 3T and 7T diffusion magnetic resonance imaging (MRI) and functional magnetic resonance imaging (fMRI) as well as behavioural and biomarker assessments at baseline and after 1 and 2 years. Both hypothesis-driven and data-driven cluster analysis approaches will be used to identify SCD sub-types based on metacognition, connectivity, behavioural and biomarkers features.CONCLUSION. COSCODE will allow defining and interpreting the constellation of signs and symptoms associated with different etiologies of SCD, paving the way to the development of cost-effective risk assessment and prevention protocols.


2020 ◽  
Vol 16 (S5) ◽  
Author(s):  
Patricia Diaz‐Galvan ◽  
Konstantinos Poulakis ◽  
Michel J. Grothe ◽  
Jurgen Fripp ◽  
Paul T. Maruff ◽  
...  

2021 ◽  
Author(s):  
Zhenrong Fu ◽  
Mingyan Zhao ◽  
Yirong He ◽  
Xuetong Wang ◽  
Xin Li ◽  
...  

Abstract Subjective cognitive decline (SCD) is characterized by self-experienced deficits in cognitive capacity with normal performance in objective cognitive tests. While, the previous structural co-variance researches showed particularly insights into understanding the structural alterations of brain in neurodegenerative diseases. However, the age-related variations in coordinated topological patterns of morphological networks in individuals with SCD remain poorly understood. In this study, 77 individual morphological networks were constructed including 42 normal controls (NC) and 35 SCD individuals from structural Magnetic Resonance Imaging (sMRI). A stepwise linear regression model was constructed to evaluate the differences of age-related alternation patterns of the network properties in individuals with SCD compared with NC. Compared with NC, the properties of integration and segregation in individuals with SCD were lower, and the aberrant metrics were negatively correlated with age in SCD, while not in NC. The connections of rich-club were persevered but the connections of paralimbic system were disrupted in SCD compared with NC. In addition, age-related differences of nodal global efficiency mainly distributed in prefrontal cortex regions. In conclusion, the age-related disruption of topological patterns in SCD provide evidence that SCD population are at high risk to cognitive decline further.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Federica Ribaldi ◽  
Christian Chicherio ◽  
Daniele Altomare ◽  
Marta Martins ◽  
Szymon Tomczyk ◽  
...  

Abstract Background Subjective cognitive decline (SCD) is the subjective perception of a decline in memory and/or other cognitive functions in the absence of objective evidence. Some SCD individuals however may suffer from very early stages of neurodegenerative diseases (such as Alzheimer’s disease, AD), minor psychiatric conditions, neurological, and/or somatic comorbidities. Even if a theoretical framework has been established, the etiology of SCD remains far from elucidated. Clinical observations recently lead to the hypothesis that individuals with incipient AD may have overestimated metacognitive judgements of their own cognitive performance, while those with psychiatric disorders typically present underestimated metacognitive judgements. Moreover, brain connectivity changes are known correlates of AD and psychiatric conditions and might be used as biomarkers to discriminate SCD individuals of different etiologies. The aim of the COSCODE study is to identify metacognition, connectivity, behavioral, and biomarker profiles associated with different etiologies of SCD. Here we present its rationale and study design. Methods COSCODE is an observational, longitudinal (4 years), prospective clinical cohort study involving 120 SCD, and 80 control study participants (40 individuals with no cognitive impairment, and 40 living with mild cognitive impairment - MCI, or dementia due to AD), all of which will undergo diffusion magnetic resonance imaging (MRI) and functional magnetic resonance imaging (fMRI) as well as behavioral and biomarker assessments at baseline and after 1 and 2 years. Both hypothesis-driven and data-driven cluster analysis approaches will be used to identify SCD sub-types based on metacognition, connectivity, behavioral, and biomarker features. Conclusion COSCODE will allow defining and interpreting the constellation of signs and symptoms associated with different etiologies of SCD, paving the way to the development of cost-effective risk assessment and prevention protocols.


2019 ◽  
Author(s):  
T. Rua ◽  
A. Isaac ◽  
S. Vijayanathan ◽  
A. Zavareh ◽  
R. Houghton ◽  
...  

GYNECOLOGY ◽  
2014 ◽  
Vol 16 (1) ◽  
pp. 69-72
Author(s):  
S.A. Martynov ◽  
◽  
L.V. Adamyan ◽  
E.A. Kulabukhova ◽  
P.V. Uchevatkina ◽  
...  

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