For early GE Signa 1.5T machines, there is a limit that total number of
slices cannot exceed 512 for any single series(e.g., 4 slice locations x
128 phases/location = 512 slices). In a Bold series, one increases the
slices to cover the full brain, decreases the phases(e.g. 16 slice x 32
phase). With TR=2.0s, the total acquisition times=64s, total slice
images=512. To prolong the time of trial and get more blocks of stimuli, I
set NEX=4 and got a 256 seconds of total scan time. The total number of
slice images is 512 and total number of volume images is 32, same as NEX=1.
Here I doubt: What is the value of "interscan interval" I should fill?
2 or 8? interscan interval=TR or =TR*NEX?
A newbie's silly question.
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