Extracting the haemodynamic response function from fMRI time series using Fourier-wavelet regularised deconvolution with orthogonal spline wavelets

Author

Wink, Alle Meije ; Roerdink, Jos B. T. M.

Author_Institution

Dept. of Psychiatry, Univ. of Cambridge, Cambridge, UK

fYear

2006

fDate

4-8 Sept. 2006

Firstpage

1

Lastpage

5

Abstract

We describe a method to extract the haemodynamic response function (HRF) from functional magnetic resonance imaging (fMRI) time series based on Fourier-wavelet regularised deconvolution (ForWaRD), and introduce a simple model for the HRF. The HRF extraction algorithm extends the ForWaRD algorithm by introducing a more efficient computation in the case of very long wavelet filters. We compute shift-invariant discrete wavelet transforms (SIDWT) in the frequency domain, and apply ForWaRD using orthogonal spline wavelets. Extraction and modelling of subject-specific HRFs is demonstrated, as well as the use of these HRFs in a subsequent brain activation analysis. Temporal responses are predicted by using the extracted HRF coefficients. The resulting activation maps show the effectiveness of the proposed method.

Keywords

Fourier transforms; biomedical MRI; brain; deconvolution; discrete wavelet transforms; feature extraction; haemodynamics; medical image processing; time series; Fourier-wavelet regularised deconvolution; brain activation analysis; fMRI time series; frequency domain; functional magnetic resonance imaging; haemodynamic response function coefficients; orthogonal spline wavelets; shift-invariant discrete wavelet transforms; subject-specific HRF extraction; Abstracts; Biomedical imaging; Discrete wavelet transforms; Splines (mathematics); Time series analysis; Timing; Vectors;

fLanguage

English

Publisher

ieee

Conference_Titel

Signal Processing Conference, 2006 14th European

Conference_Location

Florence

ISSN

2219-5491

Type

conf

Filename

7071526