Temporal sensitivity of event-related fMRI.
The temporal resolution of event-related fMRI is limited by the low sampling rate of typical MR whole brain protocols and by the slow rate of the BOLD response. Within the assumptions of the General Linear Model, we explore the tolerance of regression analyses of fMRI data to errors in the timing of the model relative to the experimental data under a number of circumstances. Given the sensitivity of the analysis to temporal shifts of the model relative to the data, one can search for the time a neuronal event occurs with temporal resolution on the order of a few hundred milliseconds with 95% confidence. This confidence level is strongly dependent on the signal-to-noise ratio of the observed BOLD responses (approximately +/-200 ms in our example of visual stimulation data collected at 1.5 T).
Hernandez
Luis
L
FMRI Laboratory, University of Michigan, Ann Arbor 48109-2108, USA.
Badre
David
D
Noll
Douglas
D
Jonides
John
J
D000465:Algorithms; D003198:Computer Simulation; D005071:Evoked Potentials; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008959:Models, Neurological; D009010:Monte Carlo Method; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation; D012044:Regression Analysis; D015203:Reproducibility of Results; D013702:Temporal Lobe / Q000502:physiology*
D010100:Oxygen