Theoretical results demonstrate fundamental differences in venous BOLD reducing fMRI activation methods
Nencka A, Rowe D
Medical College of Wisconsin
Although often discarded from the analysis of the complex-valued fMRI time series, the phase may contain fundamental information about the source of the BOLD signal. Rowe and Logan's complex constant phase and Menon's phase regressor methods both utilize the phase and magnitude time courses to bias against declaring voxels with task related phase changes (TRPCs) caused by draining veins active. These simulations which determine the different methods' powers of finding voxels of different TRPC/CNR combinations active indicate a marked difference between the complex constant phase and phase regressor methods. The complex constant phase method exhibits more optimal behavior.