BIOMEDICAL IMAGING GROUP (BIG)
Laboratoire d'imagerie biomédicale (LIB)

Analysis of fMRI Data Using Spline Wavelets

M. Feilner, T. Blu, M. Unser

Proceedings of the Tenth European Signal Processing Conference (EUSIPCO'00), Tampere, Republic of Finland, September 4-8, 2000, vol. IV, pp. 2013-2016.

Our goal is to detect and localize areas of activation in the brain from sequences of fMRI images. The standard approach for reducing the noise contained in the fMRI images is to apply a spatial Gaussian filter which entails some loss of details. Here instead, we consider a wavelet solution to the problem, which has the advantage of retaining high-frequency information. We use fractional-spline orthogonal wavelets with a continuously-varying order parameter alpha; by adjusting alpha, we can balance spatial resolution against frequency localization. The activation pattern is detected by performing multiple (Bonferroni-corrected) t-tests in the wavelet domain. This pattern is then localized by inverse wavelet transform of a thresholded coefficient map.

In order to compare transforms and to select the best alpha, we devise a simulation study for the detection of a known activation pattern. We also apply our methodology to the analysis of acquired fMRI data for a motor task. 

@INPROCEEDINGS(http://bigwww.epfl.ch/publications/feilner0001.html,
AUTHOR="Feilner, M. and Blu, T. and Unser, M.",
TITLE="Analysis of {fMRI} Data Using Spline Wavelets",
BOOKTITLE="Proceedings of the Tenth European Signal Processing
	Conference ({EUSIPCO'00})",
YEAR="2000",
editor="",
volume="{IV}",
series="",
pages="2013--2016",
address="Tampere, Republic of Finland",
month="September 4-8,",
organization="",
publisher="",
note="")
© 2000 EURASIP. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from EURASIP. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.