## Abstract In BOLD fMRI data analysis, robust and accurate estimation of the Hemodynamic Response Function (HRF) is still under investigation. Parametric methods assume the shape of the HRF to be known and constant throughout the brain, whereas nonβparametric methods mostly rely on artificially in
Event-related fMRI and the hemodynamic response
β Scribed by Randy L. Buckner
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 237 KB
- Volume
- 6
- Category
- Article
- ISSN
- 1065-9471
No coin nor oath required. For personal study only.
β¦ Synopsis
Event-related functional magnetic resonance imaging (ER-fMRI) methods are allowing a new spectrum of task designs to be explored with brain imaging techniques. Individual trial events can be presented rapidly, in randomly intermixed order, and the hemodynamic responses associated with individual trial events appreciated. The basis of ER-fMRI is that the hemodynamic response tracks neuronal activity on the order of seconds and, in many situations, summates over trials in a manner well predicted by a linear model--even for trials spaced as briefly as 2 sec apart. These properties are discussed, as well as certain basic characteristics of the hemodynamic response in the context of ER-fMRI.
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