Within-subject variability of BOLD response dynamics.
In this paper we investigate the within-subject variability of dynamical aspects of the BOLD response obtained in a series of fMRI sessions several days apart. Five different parameters describing the temporal behavior of trial-averaged time courses, such as time-to-peak and time-to-onset, were estimated and analyzed with respect to their variability across nine sessions. Results show that small variances of the estimated parameters can be found, provided that the analysis is restricted to voxels activated in all individual sessions. Among the investigated parameters, time-to-peak shows the most stable behavior. These results were obtained using two different analysis methods, the estimation of the parameters directly from trial-averaged time courses and fitting trial-averaged time courses to an assumed hemodynamic response function. Both methods yield comparable results.
Neumann
Jane
J
Max-Planck-Institute of Cognitive Neuroscience, Stephanstrasse 1a, D-04103 Leipzig, Germany. neumann@cns.mpg.de
Lohmann
Gabriele
G
Zysset
Stefan
S
von Cramon
D Yves
DY
D000328:Adult; D000465:Algorithms; D001923:Brain Chemistry / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply / Q000378:metabolism / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply / Q000378:metabolism / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood*; D010296:Parietal Lobe / Q000098:blood supply / Q000378:metabolism / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology; D015203:Reproducibility of Results; D014793:Visual Cortex / Q000098:blood supply / Q000378:metabolism / Q000502:physiology
D010100:Oxygen