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Adaptive Mean Shift Based Hemodynamic Brain Parcellation in fMRI

Albughdadi, Mohanad and Chaari, Lotfi and Tourneret, Jean-Yves Adaptive Mean Shift Based Hemodynamic Brain Parcellation in fMRI. (2016) In: 7th International Conference on Medical Imaging and Augmented Reality (MIAR 2016), 24 August 2016 - 26 August 2016 (Bern, Switzerland).

(Document in English)

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Official URL: http://dx.doi.org/10.1007/978-3-319-43775-0_22


One of the remaining challenges in event-related fMRI is to discriminate between the vascular response and the neural activity in the BOLD signal. This discrimination is done by identifying the hemodynamic territories which differ in their underlying dynamics. In the literature, many approaches have been proposed to estimate these underlying dynamics, which is also known as Hemodynamic Response Function (HRF). However, most of the proposed approaches depend on a prior information regarding the shape of the parcels (territories) and their number. In this paper, we propose a novel approach which relies on the adaptive mean shift algorithm for the parcellation of the brain. A variational inference is used to estimate the unknown variables while the mean shift is embedded within a variational expectation maximization (VEM) framework to allow for estimating the parcellation and the HRF profiles without having any prior information about the number of the parcels or their shape. Results on synthetic data confirms the ability of the proposed approach to estimate accurate HRF estimates and number of parcels. It also manages to discriminate between voxels in different parcels especially at the borders between these parcels. In real data experiment, the proposed approach manages to recover HRF estimates close to the canonical shape in the bilateral occipital cortex.

Item Type:Conference or Workshop Item (Paper)
Additional Information:Thanks to Springer editor. This papers appears in Volume 9805 of Lecture Notes in Computer Science ISSN : 0302-9743 ISBN: 978-3-319-43774-3 The original PDF is available at: http://link.springer.com/chapter/10.1007/978-3-319-43775-0_22
HAL Id:hal-01466644
Audience (conference):International conference proceedings
Uncontrolled Keywords:
Institution:Université de Toulouse > Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE)
Université de Toulouse > Université Toulouse - Jean Jaurès - UT2J (FRANCE)
Université de Toulouse > Université Toulouse 1 Capitole - UT1 (FRANCE)
Laboratory name:
Deposited On:26 Jan 2017 12:41

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