Skip to content

fMRI Protocols

Taylor Salo edited this page Mar 7, 2022 · 4 revisions

Some of the custom protocols available at the CIS are documented here.

Multiband

Also known as simultaneous multislice. Acquires two or more slices simultaneously in each volume to dramatically reduce TR.

Protocol Concerns

Remember to ensure that the number of slices divided by the multiband factor is an odd number. See https://osf.io/nxtkv/, but here is a quote from Page 7:

Generally, if you use MB/SMS with an interleaved acquisition, make sure the number of slices divided by the MB/SMS factor equals an odd number (Fig. 6). For example, 10 slices and SMS= 2 (10/2 = 5) is better than 12 slices and SMS = 2 (12/2 = 6). If it is an even number, the slice groups can interfere with each other and create artifacts.

Processing Concerns

Multi-echo

Acquires two or more acquisitions with different echo times in each volume. Helps differentiate BOLD and non-BOLD signal in T2* scans. Great introduction available here and one of the original papers here.

Processing Concerns

Processing multi-echo data is generally done with Multi-Echo Independent Components Analysis (ME-ICA). There is an AFNI program and a Bitbucket repository for performing ME-ICA.