Artificial shifting of fMRI activation localized by volume- and surface-based analyses
- Authors
- Jo, Hang Joon; Lee, Jong-Min; Kim, Jae-Hun; Choi, Chi-Hoon; Gu, Bon-Mi; Kang, Do-Hyung; Ku, Jeonghun; Kwon, Jun Soo; Kim, Sun I.
- Issue Date
- Apr-2008
- Publisher
- ACADEMIC PRESS INC ELSEVIER SCIENCE
- Keywords
- functional magnetic resonance imaging; activation detection; surface-based method; localization; MRI methods/techniques
- Citation
- NEUROIMAGE, v.40, no.3, pp.1077 - 1089
- Indexed
- SCIE
SCOPUS
- Journal Title
- NEUROIMAGE
- Volume
- 40
- Number
- 3
- Start Page
- 1077
- End Page
- 1089
- URI
- https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/178819
- DOI
- 10.1016/j.neuroimage.2007.12.036
- ISSN
- 1053-8119
- Abstract
- Spatial smoothing is an important post-processing procedure that is used to increase the signal-to-noise ratio (SNR) of blood oxygenation level-dependent signals (BOLD) in common functional magnetic resonance imaging (fMRI) applications. However, recent studies have shown that smoothing artificially shifts probabilistic local maxima of fMRI activations. In this study, we show shifting of the localization of functional centers in hand motor areas of the cerebral cortex by three-dimensional isotropic Gaussian kernel smoothing or two-dimensional heat kernel smoothing in volume-and surface-based fMRI analyses. Activation maps derived from smoothed echo planar imaging (EPI) data by volume-and surface-based analyses were assigned to the nodes of individual cortical surface models, and local maxima in the primary motor area (M1) and the primary somatosensory cortex (S1) were compared with those derived from non-smoothed risk map analysis, which is commonly used in presurgical applications. For each analysis, the Euclidean and geodesic distances between the correlation coefficients of local maxima derived from smoothed and non-smoothed EPI data were measured. The results show that the correlation coefficients derived from the volume-and surface-based analyses were about 29.4% and 42.9% higher for smoothed than for non-smoothed risk map analyses, and show minimum shifting of localizations by 12.1 mm and 6.9 mm on average in Euclidean distance, respectively, and about 9.5 mm and 5.7 mm on average in geodesic distance, respectively.
- Files in This Item
-
Go to Link
- Appears in
Collections - 서울 의과대학 > 서울 생리학교실 > 1. Journal Articles
![qrcode](https://api.qrserver.com/v1/create-qr-code/?size=55x55&data=https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/178819)
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.