PREPROCESSING STEPS IN fMRI: SMOOTHING

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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