Comparative Study on the Topological Attributes of Deficiency and Excess Pattern of Cerebral Small Vessel Disease Mild Cognitive Impairment Based on fMRI Graph Theory Network / 世界科学技术-中医药现代化

Objective This study aimed to explore the differences in global and local brain network topological properties between deficient pattern(DP)and excess pattern(EP)of mild vascular cognitive impairment caused by subcortical small vessel disease based on graph theory network.Methods Patients were recruited prospectively and were classified with DP and EP subtype.The global small-world topological attributes and local nodes were calculated for the comparison of DP,EP,and healthy controls(CN)using the GRETNA platform.Results The three groups all had small-world attributes,but only the patients in EP had a significantly lower small world attribute δ in the range of 0.05-0.26 than the control group(P<0.05).The node efficiency and node strength indicators of multiple brain region were able to significantly distinguish the DP group from the EP group.However,there was no positive brain region in the node efficiency of the DP patients(P>0.05),and only a few brain regions showed increased node strength efficiency(P<0.05).Conclusion The results indicate that the syndrome of DP and EP have significantly different neuroimaging phenotypes,providing a basis for further research of biological classification based on Chinese Medicine syndromes.

Research progress of large-scale brain network of Alzheimer's disease based on MRI analysis / 实用医学杂志

With the advent of an aging society,Alzheimer's disease(AD)has gradually become a major ailment affecting the elderly.AD is a neurodegenerative disorder associated with cognitive impairments.In AD patients,brain network connections are disrupted,and their topological properties are also affected,leading to the disintegration of anatomical and functional connections.Anatomical connections can be tracked and evaluated using structural magnetic imaging(MRI)and diffusion tensor imaging(DTI),while functional connections are detected through functional MRI to assess their connectivity status.This review incorporates the findings of previous scholars and summarizes the current research of AD.It mainly discusses the imaging characteristics of large-scale brain network changes in AD patients,so as to provide researchers with scientific and objective imaging markers for AD prediction and early diagnosis,as well as future research.

Relationship between Small-world Network and Cognitive Impairment for Patients with White Matter Lesions Based On Diffusion Tensor Imaging / 中国康复理论与实践

Objective:To explore the relationship between small-worldness of brain network and cognitive impairment in patients with white matter lesions (WMLs) based on diffusion tensor imaging (DTI). Methods:From January, 2016 to December, 2017, 46 WMLs patients and 36 controls matched genders, ages and education levels from Beijing Tiantan Hospital were screened with DTI. The patients were divided into vascular cognitive impairment non-dementia (VCIND) and vascular dementia (VaD) groups according to the results of cognitive assessments. The brain structure network was created based on DTI data, and the topological properties of the whole-brain small-world network were calculated, and the correlation between the small-worldness and the severity of cognitive impairment was analyzed. Results:The global efficiency, local efficiency, shortest path length and clustering coefficient were different between the patients and the controls (F > 3.252, P < 0.05), as well as the properties of the small-world network, λ, γ and σ (F > 7.378, P < 0.01). The λ, γ and σ were correlated with the total score of Montreal Cognitive Assessment (|r| > 0.402, P < 0.05). Conclusion:The brain structure network is small-world network for patients with WMLs, and the decrease of small-world properties may relate to the cognitive impairment.

Small-world Network Features of Brain Functional Network as Strong Void Perception for Healthy Female / 中国康复理论与实践

Objective:To identify the small-world network property of brain functional network provoked by a strong desire to void in healthy women. Methods:From 2017 to 2018, 21 healthy women were enrolled, and scanned with resting-state functional magnetic resonance imaging under the empty bladder and strong desire to void, respectively. Brain connection matrix was established with Pearson's correlation analysis, and the differences in topologic properties between the two conditions were identified with paired t-test and Bonferroni correction. The small-world parameters, named clustering coefficient (Cp), characteristic path length (Lp), global efficiency (Eglob), local efficiency (Eloc) and nodal efficiency (Enodal) were calculated. Results:There were two women dropped down because of head moving. For the other 19 women, the brain connection presented a small-world network property under the both conditions. Compared with the empty bladder, Cp, Lp, and Eloc decreased, and Eglob increased under the strong desire to void (P < 0.05); while Enodal increased in left inferior frontal gyrus and superior frontal gyrus; right cingulate gyrus, middle occipital gyrus and middle temporal gyrus; and bilateral gyrus rectus and inferior parietal lobes; and decreased in bilateral fusiform gyrus, calcarine fissure and surrounding, and lingual gyrus (P < 0.05). Conclusion:Brain functional network presents a small-world network property under both empty bladder and a strong desire to void. The regulation of lower urinary tract function involves the coordination of multiple brain regions.

Analysis of imagery motor effective networks based on dynamic partial directed coherence / 生物医学工程学杂志

The research on brain functional mechanism and cognitive status based on brain network has the vital significance. According to a time-frequency method, partial directed coherence (PDC), for measuring directional interactions over time and frequency from scalp-recorded electroencephalogram (EEG) signals, this paper proposed dynamic PDC (dPDC) method to model the brain network for motor imagery. The parameters attributes (out-degree, in-degree, clustering coefficient and eccentricity) of effective network for 9 subjects were calculated based on dataset from BCI competitions IV in 2008, and then the interaction between different locations for the network character and significance of motor imagery was analyzed. The clustering coefficients for both groups were higher than those of the random network and the path length was close to that of random network. These experimental results show that the effective network has a small world property. The analysis of the network parameter attributes for the left and right hands verified that there was a significant difference on ROI2 ( = 0.007) and ROI3 ( = 0.002) regions for out-degree. The information flows of effective network based dPDC algorithm among different brain regions illustrated the active regions for motor imagery mainly located in fronto-central regions (ROI2 and ROI3) and parieto-occipital regions (ROI5 and ROI6). Therefore, the effective network based dPDC algorithm can be effective to reflect the change of imagery motor, and can be used as a practical index to research neural mechanisms.

Small world networks of brain network in mild traumatic brain injury patients:a functional magnetic resonance image study / 中华行为医学与脑科学杂志

Objective To analyze the effects of mild traumatic brain injury ( mTBI) on functional brain network parameters and to study the properties of small world of patients. Methods Ten patients with mild traumatic brain injury and 13 healthy controls matched by age and sex were collected from the Ninth People's Hospital Affiliated to Medical College of Shanghai Jiao Tong University. Resting functional magnetic resonance images of all subjects were collected. Functional networks were constructed and brain network properties were analyzed. Results The brain injury group and the healthy control group had small world at-tributes in the selected sparseness range. The global efficiency of patients with mTBI patients was significantly reduced compared to healthy control group (0. 174±0. 141 vs 0. 184±0. 062),t=2. 417,P=0. 025),and the shortest path length was increased compared to healthy control group (0. 797±0. 930 vs 0. 734±0. 488),t=-2. 083,P=0. 048). Conclusion The functional brain network of patients with mTBI patients has small world attributes,and the parameters of functional brain network of patients have changed.

Radiation-induced changes in small world network in patients with nasopharyngeal carcinoma: a three-dimensional structure MRI imaging study / 中华放射肿瘤学杂志

Objective@#To investigate the radiotherapy (RT)-induced changes in the brain structural network in patients with nasopharyngeal carcinoma (NPC).@*Methods@#Three-dimensional structural magnetic resonance data (3D-T1W) was adopted to investigate the structural network in 103 patients with NPC before and after receiving RT. The structural networks were then reconstructed using 3D-T1W. The radiation-induced changes in topology properties of small world network were analyzed by using graph theoretical analysis.@*Results@#Patients showed small world properties before and after RT. Compared with the pre-RT group, the global and local efficiency were lower, the shortest path length was longer and the clustering coefficient was less in the post-RT group. In addition, the hub regions in the post-RT group were significantly different from those in the pre-RT group, mainly located in the left rolandic operculum, right inferior frontal gyrus, right parahippocampal gyrus, right lingual gyrus, bilateral supramarginal gyrus, left superior temporal gyrus and temporal pole of the right middle temporal gyrus.@*Conclusion@#It is speculated that RT leads to high efficiency of network topology and information transmission, which provides a novel perspective for exploring the RT-induced brain changes, diagnosis of RT-induced injury and evaluation of RT efficacy.

Primary comparative study on the functional properties of cerebral resting state networks in neonates with hypoxic ischemic encephalopathy / 中华行为医学与脑科学杂志

Objective To explore the functional properties of the brain's resting state networks in neonates with hypoxic ischemic encephalopathy.Methods Use the methods of functional MRI probabilistic tractography and graph theory to compare the global and local functional properties of the brain's resting state network between 12 cases of children with mild HIE and 14 cases of children with moderate/severe HIE.Results In terms of global topological properties,both the mild and moderate/severe group showed small-world properties.The γ and λ in the mild group were 2.450± 1.642 and 1.542±0.564 and in the moderate/severe group were 2.331± 1.554 and 1.353±0.672,respectively,which were in line with the characteristics of small-world properties (γ＞ 1 and λ ≈ 1).As far as local topological properties were concerned,the distribution of hub regions in the functional networks had smaller number of nodes in the moderate/severe group (8 nodes) than the mild group (14 nodes).The comparison of nodal efficiencies showed that the moderate/severe group had significantly reduced nodal efficiency in the left insula opercula,left supramarginal gyrus,left and right temporal pole and right middle temporal gyrus(the nodal efficiencies of the moderate/severe group:0.4089±0.0865,0.3377±0.1223,0.3842±0.0898,0.3508±0.1295,0.3564±0.0843;the nodal efficiencies of the mild group:0.4801±0.0762,0.4465±0.0898,0.4655 ±0.0812,0.4640±0.0690,0.4271±0.0636,all P＜0.05).Conclusion The topological structure of resting state functional network in children with moderate and severe hypoxic-ischemic encephalopathy is obviously backward than that in children with mild hypoxic-ischemic encephalopathy,which may be related to abnormal language,movement and cognitive function in the late stage.

The research on dynamic properties of the small world neural network based on the synaptic plasticity / 生物医学工程学杂志

The artificial neural network has the ability of the information processing and storage, good adaptability, strong learning function, association function and fault tolerance function. The research on the artificial neural network is mostly focused on the dynamic properties due to fact that the applications of artificial neural networks are related to its dynamic properties. At present, the researches on the neural network are based on the hierarchical network which can not simulate the real neural network. As a high level of abstraction of real complex systems, the small world network has the properties of biological neural networks. In the study, the small world network was constructed and the optimal parameter of the small word network was chosen based on the complex network theory firstly. And then based on the regulation mechanism of the synaptic plasticity and the topology of the small world network, the small world neural network was constructed and dynamic properties of the neural network were analyzed from the three aspects of the firing properties, dynamic properties of synaptic weights and complex network properties. The experimental results showed that with the increase of the time, the firing patterns of excitatory and inhibitory neurons in the small world neural network didn't change and the firing time of the neurons tended to synchronize; the synaptic weights between the neurons decreased sharply and eventually tended to be steady; the connections in the neural network were weakened and the efficiency of the information transmission was reduced, but the small world attribute was stable. The dynamic properties of the small world neural network vary with time, and the dynamic properties can also interact with each other: the firing synchronization of the neural network can affect the distribution of synaptic weights to the minimum, and then the dynamic changes of the synaptic weights can affect the complex network properties of the small world neural network.

Small-world networks analysis of leukoaraiosis: a rest-state functional MRI study / 中华行为医学与脑科学杂志

Objective To explore the effect of leukoaraiosis (LA) on the efficiency of the brain function network and to analyze the features of the "small world" network with graph theory method.Methods This study involved 34 LA patients from the Department of Neurology,Beijing Tiantan hospital,Capital Medical University from January 2014 to September 2015 and 23 age-and sex-matched healthy controls(NC group).All participants underwent the neurocognitive tests including M MSE,MoCA and clinical dementia rating(CDR).The subjects were divided into LA with cognitive normal group (CN) (n=11) and LA patients with vascular cognitive impairment-non dementia group(VCIND) (n=23).Functional MRI (fMRI) was employed at resting state.And then,the functional network establishment and small-world network metrics (characteristic clustering coefficient and path length) were computed using graph analytical methods.Results In the range of 0.05 ≤ Kcost ≤ 0.5,the functional networks fitted the definition of small-worldness in LA (CN),LA(VCIND) and NC groups(δ＞1).The Lambda of group LA(CN) and LA (VCIND) were smaller than that of NC group at each threshold,and more closing to 1.The gamma of group LA(CN) were higher than that of NC group at each threshold.While the gamma of group LA(VCIND)were lower than that of NC group at each threshold.The sigma of group LA(CN) were higher than that of NC group at each threshold.Conclusion The LA patients exhibit abnormal small-world network properties.And compared with HCs,small world properties in LA (CN) patients have been increased,while that in LA (VCIND) patients have been reduced,which manifested that the altered topological properties may be responsible for cognitive dysfunction in LA patients.

Quantitative study of meridian topology model based on acupoint-symptom relationship / 中国针灸

Meridian theory plays an important role in the guidance of clinical practice of acupuncture and moxibustion. Since the publication of(), the meridian theory has been developed. In the paper, in view of complex science, the topological properties of acupoint-symptom network were analyzed quantitatively by taking acupoint as node and indication as the connection, such as high clustering coefficient and the small world effect. It was the first time to give the abstraction for the topological proof of the high efficiency information transmission property of acupoint-symptom network meridian system at different times. Its quantitative and digitalized significance was analyzed on the development of meridian theory under the complex scientific background so as to provide a new thought and method for the study of meridian theory and acupuncture modernization.

Scale-free and small-world properties in co-occurrence networks of major MeSH terms and all MeSH terms in MEDLINE / 中华医学图书情报杂志

Co-occurrence network of major MeSH terms and all MeSH terms was constructed respectively with MEDLINE-covered pharmacological literature as its example.The degree, closeness and betweenness of centrality in different nodes of the two co-occurrence networks were analyzed , the distribution of scale-free properties in the two co-occurrence networks was tested, the small-world effect of the two co-occurrence networks was identified by comparing their overall properties ( average distance and clustering coefficient ) , which showed the scale-free properties and small-world effect of the two co-occurrence networks.The co-occurrence network of all MeSh terms could thus be used in analysis of network properties while that of major MeSH terms could thus be used in analysis of subject contents.

A preliminary study of the topological patterns of the brain structural networks and its relationship with the course in depression / 中华行为医学与脑科学杂志

Objective To investigate the small-worldness and the betweenness centrality of the nodes in the brain structural networks and its relationship with the course and the central role of the brain regions in the transmission of information across the whole brain in depression.Methods The diffusion tensor imaging data were obtained from 27 depression patients and 33 healthy controls.The brain structural networks were constructed using the complex network theory.Results The brain structural networks had small-world properties in both groups.When compared with the healthy,the betweenness centrality of the nodes of the networks in depression significantly decreased in right superior frontal gyms (orbital part) (P=0.00035,region survived critical FDR threshold for multiple comparisons),and left putamen (P=0.00054,region survived critical FDR threshold for multiple comparisons).Significant negative correlation was found between the betweenness centrality of left hippocampus and the course in the depression(r=0.50,P=0.016).Conclusion Both of the brain structural networks in depression patients and normal people have the property of small-worldness.But the central role of orbit frontal cortex and putamen in the transmission of information across the whole brain is declined,and the betweenness centrality of hippocampus is negatively related with the course in the depression.

The small world networks property and cognitive function in the frontal low-grade glioma patients:a preand-postoperative fMRI study / 中华行为医学与脑科学杂志

Objective To explore the property of brain functional networks and cognitive function changes in patients with frontal lobe low-grade gliomas (LGG).Methods 8 cases of suspected frontal lobe LGG patients were undergone with resting-fMRI scanning to analyze the small-world property of the LGG,meanwhile the LGG groups had Montreal (MoCA) cognitive score exam compared with the control group.Results The value of MoCA was 22.5 ± 1.5,21.8 ± 2.0,and 27.9 ± 2.1 respectively with statistical significance (P ＜ 0.05) in the LGG groups and the control groups.The LGG group cognitive score was significantly lower than that in the control group with statistical significance (P＜ 0.05).As to threshold,the two groups were consistent with the small world property.The LGG local efficiency was smaller than that of the controls,the postoperative small world properties (σ=2.49) were lower than that the pre-operative (σ =2.68),the largest brain function areas of preoperative information transmission were respectively the supramarginal gyrus,posterior cingulate,insula,and the postoperative being the precuneus,calcarine sulcus and superior frontal gyrus.The maximum cluster coefficient of the preoperative functional network were respectively the entorhinal cortex,transverse temporal gyrus and the calcarine sulcus,and postoperative were Wilson,transverse temporal gyri and occipital gyrus.Preoperative information transmission path was less than the postoperative,and the small world properties were positively correlated with MoCA.Conclusion LGG accompany by the changes of cognitive function,and with the small world network property preand post-operation.

Anatomical Brain Connectivity Map of Korean Children

PURPOSE: The purpose of this study is to establish the method generating human brain anatomical connectivity from Korean children and evaluating the network topological properties using small-world network analysis. MATERIALS AND METHODS: Using diffusion tensor images (DTI) and parcellation maps of structural MRIs acquired from twelve healthy Korean children, we generated a brain structural connectivity matrix for individual. We applied one sample t-test to the connectivity maps to derive a representative anatomical connectivity for the group. By spatially normalizing the white matter bundles of participants into a template standard space, we obtained the anatomical brain network model. Network properties including clustering coefficient, characteristic path length, and global/local efficiency were also calculated. RESULTS: We found that the structural connectivity of Korean children group preserves the small-world properties. The anatomical connectivity map obtained in this study showed that children group had higher intra-hemispheric connectivity than inter-hemispheric connectivity. We also observed that the neural connectivity of the group is high between brain stem and motorsensory areas. CONCLUSION: We suggested a method to examine the anatomical brain network of Korean children group. The proposed method can be used to evaluate the efficiency of anatomical brain networks in people with disease.

Preliminary Prooerties of Meridian System as a Complex Network / 针灸推拿医学（英文版）

The system of meridians and acupoints in the traditional Chinese medication (TCM) builds up a complex network. We analyze the features and properties of the system of meridians and acupoints as a complex network based on knowledge of TCM and mathematics. The system shows some important features of complex networks such as the small-world effect and the scale-free property. A preliminary discussion on the robustness of the meridian system as a complex network, and the biomedical functions of such robustness is also given.