Abstract
BOLD fMRI is accepted as a noninvasive imaging modality for neuroimaging and brain mapping. A BOLD fMRI dataset consists of magnitude and phase components. Currently, only the magnitude is used for neuroimage analysis. In this paper, we show that the fMRI-magnitude-based neuroimage analysis may suffer two pitfalls: one is that the magnitude is non-negative and cannot differentiate positive from negative BOLD activity; the other is an edge effect that may manifest as an edge enhancement or a spatial interior dip artifact at a local uniform BOLD region. We demonstrate these pitfalls via numeric simulations using a BOLD fMRI model and also via a phantom experiment. We also propose a solution by making use of the fMRI phase image, the counterpart of the fMRI magnitude.
Original language | English (US) |
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Pages (from-to) | 363-369 |
Number of pages | 7 |
Journal | Journal of Neuroscience Methods |
Volume | 199 |
Issue number | 2 |
DOIs | |
State | Published - Aug 15 2011 |
Externally published | Yes |
Keywords
- BOLD fMRI
- BOLD susceptibility
- Computational neuroimaging
- Edge enhancement
- Small angle regime
ASJC Scopus subject areas
- General Neuroscience