Optimalization of Event-Related FMRI Design for BOLD Deconvolution

Johan Martijn Jansma¹, Jacco A. de Zwart², Peter van Gelderen², Wayne C. Drevets¹, Maura L. Furey

Because BOLD response timing can vary across regions and subjects, model free fMRI signal analysis through deconvolution (a.k.a. FIR) analysis can be preferred above methods that apply an a-priori BOLD model. A disadvantage is the larger number of regressors, which can increase regressor dependency. The effect of regressor dependency (expressed as the average tolerance or aTOL) on sensitivity and reliability of multi-regressor-based deconvolution analysis is investigated here. Comparison, through simulations and experimental data, of 128 random regressors with a pseudo-random m-sequence design indicated that performance of the design scaled with aTOL and that the m-sequence consistently outperformed all random designs.