Two pitfalls of BOLD fMRI magnitude-based neuroimage analysis: Non-negativity and edge effect

Zikuan Chen, Vince D. Calhoun

Research output: Contribution to journalArticlepeer-review

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 languageEnglish (US)
Pages (from-to)363-369
Number of pages7
JournalJournal of Neuroscience Methods
Volume199
Issue number2
DOIs
StatePublished - Aug 15 2011
Externally publishedYes

Keywords

  • BOLD fMRI
  • BOLD susceptibility
  • Computational neuroimaging
  • Edge enhancement
  • Small angle regime

ASJC Scopus subject areas

  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Two pitfalls of BOLD fMRI magnitude-based neuroimage analysis: Non-negativity and edge effect'. Together they form a unique fingerprint.

Cite this