Very large fMRI study using the IMAGEN database: sensitivity - specificity and population effect modelling in relation to the underlying anatomy
Citation:
Benjamin Thyreau, Yannick Schwartz, Bertrand Thirion, Vincent Frouin, Eva Loth, Sabine Vollsätdt-Klein, Tomas Paus, Eric Artiges, Patricia J. Conrod, Gunter Schumann, Robert Whelan, Jean-Baptiste Poline, Very large fMRI study using the IMAGEN database: sensitivity - specificity and population effect modelling in relation to the underlying anatomy, NeuroImage, 61, 1, 2012, 295 - 303Download Item:
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Abstract:
In this paper we investigate the use of classical fMRI Random Effect (RFX) group statistics when analysing a very large cohort and the possible improvement brought from anatomical information. Using 1326 subjects from the IMAGEN study, we first give a global picture of the evolution of the group effect t-value from a simple face-watching contrast with increasing cohort size. We obtain a wide activated" pattern, far from being limited to the reasonably expected brain areas, illustrating the difference between statistical significance and practical significance. This motivates us to inject tissue-probability information into the group estimation, we model the BOLD contrast using a matter-weighted mixture of Gaussians and compare it to the common, single-Gaussian model. In both cases, the models parameters are estimated per-voxel for one subgroup, and the likelihood of both models is computed on a second, separate subgroup to reflect models generalization capacity. Various group sizes are tested, and significance is asserted using a 10-fold cross-validation scheme. We conclude that adding matter information consistently improves the quantitative analysis of BOLD responses in some areas of the brain, particularly those where accurate inter-subject registration remains challenging.
Sponsor
Grant Number
European Commission
037286
Author's Homepage:
http://people.tcd.ie/whelanr3Description:
PUBLISHED
Author: WHELAN, ROBERT
Type of material:
Journal ArticleSeries/Report no:
NeuroImage61
1
Availability:
Full text availableKeywords:
Neuroscience, Brain Mapping, Likelihood Functions, Linear Models, Magnetic Resonance Imaging, MRISubject (TCD):
NeuroscienceLicences: