AN EVOLUTIONARY APPROACH TO MULTIVARIATE FEATURE SELECTION FOR FMRI PATTERN ANALYSIS

Malin ˚Aberg, Line Löken, Johan Wessberg

2008

Abstract

Multivariate pattern recognition has recently gained in popularity as an alternative to univariate fMRI analyis, although the exceedingly high spatial dimensionality has proven problematic. Addressing this issue, we have explored the effectiveness of evolutionary algorithms in determining a limited number of voxels that, in combination, optimally discriminate between single volumes of fMRI. Using a simple multiple linear regression classifier in conjunction with as few as five evolutionarily selected voxels, a subject mean single trial binary prediction rate of 74.3% was achieved on data generated by tactile stimulation of the arm compared to rest. On the same data, feature selection based on statistical parametric mapping resulted in 63.8% correct classification. Our evolutionary feature selection approach thus illustrates how, using appropriate multivariate feature selection, surprising amounts of information can be extracted from very few voxels in single volumes of fMRI. Moreover, the resulting voxel discrimination relevance maps (VDRMs) showed considerable overlap with traditional statistical activation maps, providing a model-free alternative to statistical voxel activation detection.

Paper Citation

in Harvard Style

˚Aberg M., Löken L. and Wessberg J. (2008). AN EVOLUTIONARY APPROACH TO MULTIVARIATE FEATURE SELECTION FOR FMRI PATTERN ANALYSIS . In Proceedings of the First International Conference on Bio-inspired Systems and Signal Processing - Volume 2: BIOSIGNALS, (BIOSTEC 2008) ISBN 978-989-8111-18-0, pages 302-307. DOI: 10.5220/0001064203020307

in Bibtex Style

@conference{biosignals08,
author={Malin ˚Aberg and Line Löken and Johan Wessberg},
title={AN EVOLUTIONARY APPROACH TO MULTIVARIATE FEATURE SELECTION FOR FMRI PATTERN ANALYSIS},
booktitle={Proceedings of the First International Conference on Bio-inspired Systems and Signal Processing - Volume 2: BIOSIGNALS, (BIOSTEC 2008)},
year={2008},
pages={302-307},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0001064203020307},
isbn={978-989-8111-18-0},
}

in EndNote Style

TY - CONF
JO - Proceedings of the First International Conference on Bio-inspired Systems and Signal Processing - Volume 2: BIOSIGNALS, (BIOSTEC 2008)
TI - AN EVOLUTIONARY APPROACH TO MULTIVARIATE FEATURE SELECTION FOR FMRI PATTERN ANALYSIS
SN - 978-989-8111-18-0
AU - ˚Aberg M.
AU - Löken L.
AU - Wessberg J.
PY - 2008
SP - 302
EP - 307
DO - 10.5220/0001064203020307