extracting diagnostic information from intrinsic...
TRANSCRIPT
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Comparison of multi-subject ICA methods for analysis of fMRI data:
Consistency and Variability of Intrinsic Networks in the Healthy and Diseased Brain
Vince D. Calhoun, Ph.D. Chief Technology Officer &
Director, Image Analysis & MR Research The Mind Research Network
Professor, Electrical and Computer Engineering (primary),
Psychiatry, Neurosciences, & Computer Science The University of New Mexico
Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
2
Prediction of Individual Responses is Important
3
E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011. 4
Extracting Diagnostic Information
from Intrinsic Networks
•Accurate classification requires single-subject accuracy -> very stringent requirement!
•We cannot use knowledge of the diagnosis in the development of the classification algorithm
Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
5 6
Group ICA
R L
V.D. Calhoun, T. Adali, G.D. Pearlson, and J.J. Pekar, "A Method for Making Group Inferences From Functional
MRI Data Using Independent Component Analysis," Hum. Brain Map., vol. 14, pp. 140-151, 2001.
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Single Subject ICA vs Group ICA
E. Erhardt, E. A. Allen, Y. Wei, T. Eichele, and V. D. Calhoun, "SimTB, a simulation toolbox for fMRI data under a model of spatiotemporal separability," NeuroImage, Under Review. & Poster #657. E. A. Allen, E. Erhardt, Y. Wei, T. Eichele, and V. D. Calhoun, "Capturing inter-subject variability with group independent component analysis of fMRI data: a simulation study," NeuroImage, Under Review. & Poster# 690.
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Group ICA
:
Subject 1
Subject N
Data
Subject i
Back-reconstruction through inversion1
1
Ai Si
ICA (Forward Estimation)
PCA reduction1
A S_agg
ICA
A1
AN
PCA reduction2
Subject i
Back-reconstruction through Spatial-temporal (dual) regression2,3
Ai
Si
S_agg 1) Regress onto each timepoint of to generate
Subject i Ai 2) Regress onto each image of to generate
Iterate steps 1 & 2 until converged
1. V. D. Calhoun et al Hum.Brain Map., vol. 14, pp. 140-151, 2001. 2. V. D. Calhoun et al Neuropsychopharmacology, vol. 29, pp. 2097-2107, 2004.
3. N. Filippini et al Proc Natl Acad Sci U S A, vol. 106, pp. 7209-7214, Apr 28 2009
Default Mode Group Maps
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Inversion STR
E. Erhardt, S. Rachakonda, E. Bedrick, T. Adali, and V. D. Calhoun, "Comparison of multi-subject ICA methods for analysis of fMRI data," Hum Brain Mapp, In Press.
Evaluation of Group ICA Methods
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E. Erhardt, S. Rachakonda, E. Bedrick, T. Adali, and V. D. Calhoun, "Comparison of multi-subject ICA methods for analysis of fMRI data," Hum Brain Mapp, In Press.
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X
Subject 1
Subject N
Data
A S_agg
ICA
A1
AN
Subject i
Back-reconstruction
1
Ai Si
Comp# R2 Subject Reg1 Reg2
2 0.81
1 1.89 0.02
2 2.28 0.66
10 0.80
1 0.28 2.19
2 0.65 2.03
4 0.017
1 -0.19 -0.40
2 -0.10 0.08
Component Timecourses
Task-modulation
(e.g. Fit timecourses
to GLM model then
test parameter)
Component Images
Voxel-wise stats
(e.g. one-sample t-test,
two-sample t-test,
correlation, etc)
}
}
Component
images
(one per
subject)
T-statistic
}
}
Multiple
regression
fit to ICA
timecourses
Beta-weights
(second
level
model)
} Model
timecourses
Spectra
(e.g. power spectra,
fractal parameters,
etc)
Controls-Patients
-5
-4
-3
-2
-1
0
1
2
3
4
0.03 0.08 0.13 0.19 0.24 0.3
Frequency (Hz)
T-v
alu
e
T-Values
} Component
timecourses
} Power
spectra
group
differences
Tim
e
Components Voxels Voxels
Co
mp
oe
nts
Tim
e
Tim
e
Voxels
Tim
e
Components
Functional Network
Connectivity
(e.g. inter-component
correlation)
Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
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3
Rest fMRI Networks (N=603)
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E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011.
Main Effects & MANCOVA Model
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E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011.
1
1
1
log ,..., log
,...,
atanh ,..., atanh
TT T
c c Mc
TT T
c c Mc
TT T
M
P P P
S S S
K K K
Selecting/Labeling Components
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E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011.
28 labeled components superset of 75 components
N=603 subjects http://mialab.mrn.org/data/index.html
Various Metrics for component selection Compare with below atlas
Spatial Maps
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E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011.
Functional Network Connectivity (FNC)
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E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011.
Spectra
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E. Allen, et al, "A baseline for the multivariate comparison of resting state networks," Frontiers in Human Neuroscience, vol. 1, p. 12, 2011.
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Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
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Relationship to Disease (N=1140)
Healthy (N=590) Substance Use (N=469)
Schizo/BP (N=81)
Within network example: anterior DMN Between network example:
precuneus-cerebellar connectivity
Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
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• Motivation
• Simulated data facilitate comparative evaluations
• Creating reasonable simulations can be challenging
given the complexities of fMRI data
• SimTB goals
• Flexible, easy and fast generation of simulated fMRI
data under an ICA model
• Ability to answer basic questions regarding the group
ICA model
A simulation toolbox
1
Cnn r
i ic ic ic i i i i i
c
Y g N diag N
r s R g S
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E. Erhardt, E. A. Allen, Y. Wei, T. Eichele, and V. D. Calhoun, "SimTB, a simulation toolbox for fMRI data under a model of spatiotemporal separability," NeuroImage, Under Review. & Poster #657.
Overview of simTB Spatial Maps
• Roughly 30 SMs can be selected through the graphical
user interface by clicking on components, or by component
number in the batch script
• For each subject, each selected component can be included
or not, be translated and rotated in space, and the spatial
spread of the component can be increased or decreased
• Each SM is normalized to have a peak-to-peak amplitude
range of one
Moments compared with real fMRI data
• Tissue types affect baseline intensity
• Possible to match simulation to real fMRI data
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Two paradigm examples
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• x- and y- translation and rotation
• Subject 1 (bold) has half the motion of subject 2
http://mialab.mrn.org/software
Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
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Group ICA: Pushed to the Limits
• Four Experiments
• Varied component rotation
• Varied component position
• Varied component amplitude
• Varied the temporal correlation among components
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E. A. Allen, E. Erhardt, Y. Wei, T. Eichele, and V. D. Calhoun, "Capturing inter-subject variability with group independent component analysis of fMRI data: a simulation study," NeuroImage, Under Review. & Poster #690.
http://mialab.mrn.org/software
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Rotation
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Position
32
Amplitude
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Temporal Correlation Among Components (FNC)
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Constrained ICA
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1{ ( ) } { ( : ) }
2
T TE G E g y yλ W ρ Wx x μ y W x
Q. Lin, J. Liu, Y. Zheng, H. Liang, and V. D. Calhoun, "Semi-blind Spatial ICA of fMRI Using Spatial Constraints”, Hum. Brain Map., vol. 31, 2010
Overview
• Motivation
• A brief review of group ICA
• A Testing Framework
• Application to large study
• Application to disease groups
• A Simulation Framework & Toolbox (simTB)
• Pushing the limits of Group ICA
• Summary
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Summary
• groupICA provides excellent estimates of single
subject SMs and TC and captures extensive spatial,
temporal, and amplitude variability.
• In general spatial ICA assumes consistency across
space, however estimation is surprisingly robust to
modest violation of this model.
• We introduce a tool for rapidly producing realistic
simulations of fMRI data under an ICA model.
• Enable rapidly answering questions about existing and
new ICA and group ICA approaches.
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E. Erhardt, E. A. Allen, Y. Wei, T. Eichele, and V. D. Calhoun, "SimTB, a simulation toolbox for fMRI data under a model of spatiotemporal separability," NeuroImage, Under Review. & Poster #657. E. A. Allen, E. Erhardt, Y. Wei, T. Eichele, and V. D. Calhoun, "Capturing inter-subject variability with group independent component analysis of fMRI data: a simulation study," NeuroImage, Under Review. & Poster# 690.
http://mialab.mrn.org/software
Software/Algorithms
Left Hemisphere
Visual Stimuli Onset
Left Hemisphere
Visual Stimuli Onset
http://mialab.mrn.org/software 4100+ unique downloads
Funded by: 1R01EB006841
http://mialab.mrn.org/software
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http://mialab.mrn.org Posters: #657 (M-T), #690 (W-Th)
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