PREPROCESSING STEPS IN fMRI: SMOOTHING

Year 2019, , 161 - 171, 01.12.2019

Hacer Daşgın Ali Yaman , Yılmaz Akdi

https://doi.org/10.33769/aupse.633838

Abstract

Functional
magnetic resonance imaging is a technique with a primary and dominant effect in
the investigation of the cognitive functions of the brain since it has a
complex structure. In this study, data obtained from single subject was
examined. First statistical parametric mapping results were obtained after
applying the standard preprocessing steps with including smoothness. Spatial
smoothing was performed using a 3 mm Gaussian kernel which is twice of the
voxel size. Second, statistical parametric mapping results were obtained with
applying standard preprocessing steps without smoothing. The effects of these
two applications on the mapping results were compared for selected slices and
locations in terms of statistical and pattern.

Keywords

Statistical parametric mapping (SPM), functional magnetic resonance imaging (fMRI), Gaussian kernel

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