Semi-supervised clustering for parcellating brain regions based on resting state fMRI data

AbstractNeurofeedback (NF) aptitude, which refers to an individual’s ability to change its brain activity through NF training, has been reported to vary significantly from person to person. The prediction of individual NF aptitudes is critical in clinical NF applications. In the present study, we extracted the resting-state functional brain connectivity (FC) markers of NF aptitude independent of NF-targeting brain regions. We combined the data in fMRI-NF studies targeting four different brain regions at two independent sites (obtained from 59 healthy adults and six patients with major depressive disorder) to collect the resting-state fMRI data associated with aptitude scores in subsequent fMRI-NF training. We then trained the regression models to predict the individual NF aptitude scores from the resting-state fMRI data using a discovery dataset from one site and identified six resting-state FCs that predicted NF aptitude. Next we validated the prediction model using independent test data from another site. The result showed that the posterior cingulate cortex was the functional hub among the brain regions and formed predictive resting-state FCs, suggesting NF aptitude may be involved in the attentional mode-orientation modulation system’s characteristics in task-free resting-state brain activity.

Download Full-text

Analysis of fMRI data using noise-diffusion network models: a new covariance-coding perspective

10.1101/223784 ◽

2017 ◽

Cited By ~ 1

Author(s):

Matthieu Gilson

Keyword(s):

Resting State ◽

Effective Connectivity ◽

Network Models ◽

Resting State Fmri ◽

Brain Regions ◽

Brain Network ◽

Fmri Data ◽

Second Order Statistics ◽

Proposed Model ◽

The Many

AbstractSince the middle of the 1990s, studies of resting-state fMRI/BOLD data have explored the correlation patterns of activity across the whole brain, which is referred to as functional connectivity (FC). Among the many methods that have been developed to interpret FC, a recently proposed model-based approach describes the propagation of fluctuating BOLD activity within the recurrently connected brain network by inferring the effective connectivity (EC). In this model, EC quantifies the strengths of directional interactions between brain regions, viewed from the proxy of BOLD activity. In addition, the tuning procedure for the model provides estimates for the local variability (input variances) to explain how the observed FC is generated. Generalizing, the network dynamics can be studied in the context of an input-output mapping - determined by EC - for the second-order statistics of fluctuating nodal activities. The present paper focuses on the following detection paradigm: observing output covariances, how discriminative is the (estimated) network model with respect to various input covariance patterns? An application with the model fitted to experimental fMRI data - movie viewing versus resting state - illustrates that changes in excitability and changes in brain coordination go hand in hand.

Download Full-text

Sample Entropy Combined with the K-Means Clustering Algorithm Reveals Six Functional Networks of the Brain

Entropy ◽

10.3390/e21121156 ◽

2019 ◽

Vol 21 (12) ◽

pp. 1156 ◽

Cited By ~ 1

Author(s):

Yanbing Jia ◽

Huaguang Gu

Keyword(s):

Human Brain ◽

Resting State ◽

Clustering Algorithm ◽

Resting State Fmri ◽

Brain Regions ◽

Sample Entropy ◽

Blood Oxygenation ◽

Fmri Data ◽

Functional Networks ◽

Brain Functional Networks

Identifying brain regions contained in brain functional networks and functions of brain functional networks is of great significance in understanding the complexity of the human brain. The 160 regions of interest (ROIs) in the human brain determined by the Dosenbach’s template have been divided into six functional networks with different functions. In the present paper, the complexity of the human brain is characterized by the sample entropy (SampEn) of dynamic functional connectivity (FC) which is obtained by analyzing the resting-state functional magnetic resonance imaging (fMRI) data acquired from healthy participants. The 160 ROIs are clustered into six clusters by applying the K-means clustering algorithm to the SampEn of dynamic FC as well as the static FC which is also obtained by analyzing the resting-state fMRI data. The six clusters obtained from the SampEn of dynamic FC and the static FC show very high overlap and consistency ratios with the six functional networks. Furthermore, for four of six clusters, the overlap ratios corresponding to the SampEn of dynamic FC are larger than that corresponding to the static FC, and for five of six clusters, the consistency ratios corresponding to the SampEn of dynamic FC are larger than that corresponding to the static FC. The results show that the combination of machine learning methods and the FC obtained using the blood oxygenation level-dependent (BOLD) signals can identify the functional networks of the human brain, and nonlinear dynamic characteristics of the FC are more effective than the static characteristics of the FC in identifying brain functional networks and the complexity of the human brain.

Download Full-text

ISOMAP and machine learning algorithms for the construction of embedded functional connectivity networks of anatomically separated brain regions from resting state fMRI data of patients with Schizophrenia

AIMS Neuroscience ◽

10.3934/neuroscience.2021016 ◽

2021 ◽

Vol 8 (2) ◽

pp. 295-321

Author(s):

Ioannis K Gallos ◽

◽

Kostakis Gkiatis ◽

George K Matsopoulos ◽

Constantinos Siettos ◽

...

Keyword(s):

Machine Learning ◽

Functional Connectivity ◽

Resting State ◽

Learning Algorithms ◽

Resting State Fmri ◽

Brain Regions ◽

Machine Learning Algorithms ◽

Fmri Data

Download Full-text

Functional parcellation of the hippocampus by semi-supervised clustering of resting state fMRI data

Scientific Reports ◽

10.1038/s41598-020-73328-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Hewei Cheng ◽

Hancan Zhu ◽

Qiang Zheng ◽

Jie Liu ◽

Guanghua He

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Prior Information ◽

Healthy Adult ◽

Resting State Fmri ◽

Fmri Data ◽

Functional Neuroanatomy ◽

Supervised Clustering ◽

Unsupervised Methods ◽

The Brain

Abstract Many unsupervised methods are widely used for parcellating the brain. However, unsupervised methods aren’t able to integrate prior information, obtained from such as exiting functional neuroanatomy studies, to parcellate the brain, whereas the prior information guided semi-supervised method can generate more reliable brain parcellation. In this study, we propose a novel semi-supervised clustering method for parcellating the brain into spatially and functionally consistent parcels based on resting state functional magnetic resonance imaging (fMRI) data. Particularly, the prior supervised and spatial information is integrated into spectral clustering to achieve reliable brain parcellation. The proposed method has been validated in the hippocampus parcellation based on resting state fMRI data of 20 healthy adult subjects. The experimental results have demonstrated that the proposed method could successfully parcellate the hippocampus into head, body and tail parcels. The distinctive functional connectivity patterns of these parcels have further demonstrated the validity of the parcellation results. The effects of aging on the three hippocampus parcels’ functional connectivity were also explored across the healthy adult subjects. Compared with state-of-the-art methods, the proposed method had better performance on functional homogeneity. Furthermore, the proposed method had good test–retest reproducibility validated by parcellating the hippocampus based on three repeated resting state fMRI scans from 24 healthy adult subjects.

Download Full-text

PHASE SYNCHRONIZATION IN BRAIN NETWORKS DERIVED FROM CORRELATION BETWEEN PROBABILITIES OF RECURRENCES IN FUNCTIONAL MRI DATA

International Journal of Neural Systems ◽

10.1142/s0129065713500032 ◽

2013 ◽

Vol 23 (02) ◽

pp. 1350003 ◽

Cited By ~ 30

Author(s):

D. RANGAPRAKASH ◽

XIAOPING HU ◽

GOPIKRISHNA DESHPANDE

Keyword(s):

Linear Correlation ◽

Resting State ◽

Brain Function ◽

Phase Synchronization ◽

Human Subjects ◽

Brain Connectivity ◽

Brain Networks ◽

Resting State Fmri ◽

Brain Regions ◽

Fmri Data

It is increasingly being recognized that resting state brain connectivity derived from functional magnetic resonance imaging (fMRI) data is an important marker of brain function both in healthy and clinical populations. Though linear correlation has been extensively used to characterize brain connectivity, it is limited to detecting first order dependencies. In this study, we propose a framework where in phase synchronization (PS) between brain regions is characterized using a new metric "correlation between probabilities of recurrence" (CPR) and subsequent graph-theoretic analysis of the ensuing networks. We applied this method to resting state fMRI data obtained from human subjects with and without administration of propofol anesthetic. Our results showed decreased PS during anesthesia and a biologically more plausible community structure using CPR rather than linear correlation. We conclude that CPR provides an attractive nonparametric method for modeling interactions in brain networks as compared to standard correlation for obtaining physiologically meaningful insights about brain function.

Download Full-text

Aging effect on head motion: A Machine Learning study on resting state fMRI data

Journal of Neuroscience Methods ◽

10.1016/j.jneumeth.2021.109084 ◽

2021 ◽

Vol 352 ◽

pp. 109084

Author(s):

Valeria Saccà ◽

Alessia Sarica ◽

Andrea Quattrone ◽

Federico Rocca ◽

Aldo Quattrone ◽

...

Keyword(s):

Machine Learning ◽

Resting State ◽

Aging Effect ◽

Resting State Fmri ◽

Fmri Data ◽

Head Motion ◽

Learning Study

Download Full-text

Distinguishing hypochondriasis and schizophrenia using regional homogeneity: a resting-state fMRI study and support vector machine analysis

Acta Neuropsychiatrica ◽

10.1017/neu.2021.9 ◽

2021 ◽

pp. 1-29

Author(s):

Kangyu Jin ◽

Zhe Shen ◽

Guoxun Feng ◽

Zhiyong Zhao ◽

Jing Lu ◽

...

Keyword(s):

Cognitive Function ◽

Resting State ◽

Parietal Lobe ◽

Brain Activity ◽

Resting State Fmri ◽

Brain Regions ◽

Regional Homogeneity ◽

Middle Temporal Gyrus ◽

Support Vector ◽

Fmri Study

Abstract Objective: A few former studies suggested there are partial overlaps in abnormal brain structure and cognitive function between Hypochondriasis (HS) and schizophrenia (SZ). But their differences in brain activity and cognitive function were unclear. Methods: 21 HS patients, 23 SZ patients, and 24 healthy controls (HC) underwent Resting-state functional magnetic resonance imaging (rs-fMRI) with the regional homogeneity analysis (ReHo), subsequently exploring the relationship between ReHo value and cognitive functions. The support vector machines (SVM) were used on effectiveness evaluation of ReHo for differentiating HS from SZ. Results: Compared with HC, HS showed significantly increased ReHo values in right middle temporal gyrus (MTG), left inferior parietal lobe (IPL) and right fusiform gyrus (FG), while SZ showed increased ReHo in left insula, decreased ReHo values in right paracentral lobule. Additionally, HS showed significantly higher ReHo values in FG, MTG and left paracentral lobule but lower in insula than SZ. The higher ReHo values in insula were associated with worse performance in MCCB in HS group. SVM analysis showed a combination of the ReHo values in insula and FG was able to satisfactorily distinguish the HS and SZ patients. Conclusion: our results suggested the altered default mode network (DMN), of which abnormal spontaneous neural activity occurs in multiple brain regions, might play a key role in the pathogenesis of HS, and the resting-state alterations of insula closely related to cognitive dysfunction in HS. Furthermore, the combination of the ReHo in FG and insula was a relatively ideal indicator to distinguish HS from SZ.

Download Full-text