%0 Journal Article
%A Heunis, Stephan
%A Breeuwer, Marcel
%A Caballero-Gaudes, César
%A Hellrung, Lydia
%A Huijbers, Willem
%A Jansen, Jacobus FA
%A Lamerichs, Rolf
%A Zinger, Svitlana
%A Aldenkamp, Albert P
%T The effects of multi-echo fMRI combination and rapid T*-mapping on offline and real-time BOLD sensitivity
%J NeuroImage
%V 238
%@ 1053-8119
%C Orlando, Fla.
%I Academic Press
%M FZJ-2021-05977
%P 118244 -
%D 2021
%X A variety of strategies are used to combine multi-echo functional magnetic resonance imaging (fMRI) data, yet recent literature lacks a systematic comparison of the available options. Here we compare six different approaches derived from multi-echo data and evaluate their influences on BOLD sensitivity for offline and in particular real-time use cases: a single-echo time series (based on Echo 2), the real-time T2*-mapped time series (T2*FIT) and four combined time series (T2*-weighted, tSNR-weighted, TE-weighted, and a new combination scheme termed T2*FIT-weighted). We compare the influences of these six multi-echo derived time series on BOLD sensitivity using a healthy participant dataset (N = 28) with four task-based fMRI runs and two resting state runs. We show that the T2*FIT-weighted combination yields the largest increase in temporal signal-to-noise ratio across task and resting state runs. We demonstrate additionally for all tasks that the T2*FIT time series consistently yields the largest offline effect size measures and real-time region-of-interest based functional contrasts and temporal contrast-to-noise ratios. These improvements show the promising utility of multi-echo fMRI for studies employing real-time paradigms, while further work is advised to mitigate the decreased tSNR of the T2*FIT time series. We recommend the use and continued exploration of T2*FIT for offline task-based and real-time region-based fMRI analysis. Supporting information includes: a data repository (https://dataverse.nl/dataverse/rt-me-fmri), an interactive web-based application to explore the data (https://rt-me-fmri.herokuapp.com/), and further materials and code for reproducibility (https://github.com/jsheunis/rt-me-fMRI).
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:34116148
%U <Go to ISI:>//WOS:000679333800006
%R 10.1016/j.neuroimage.2021.118244
%U https://juser.fz-juelich.de/record/904407