Hi Peter,
--> The slices (indices corresponding to order along z-axis) were acquired in the following time order:
[18 1 19 2 20 3 21 4 22 5 23 6 24 7 25 8 26 9 27 10 28 11 29 12 30 13 31 14 32 15 33 16 34 17]
--> Slice 18 was acquired at TR/2.
Wouldn't slices 26 be your reference slice (the middle in time of your sequence). IMO in safer to specify in time (in the json file of your image) and choose the time of reference
--> The mircrotime is how many bins you split your model signal since default is 16 the middle is 8 -- same as the middle in time of your slice timing (alternatively, specify 34 time bins and 17 as onset).
Cyril
-----Original Message-----
From: SPM (Statistical Parametric Mapping) <[log in to unmask]> On Behalf Of Peter Sp
Sent: 21 November 2019 09:04
To: [log in to unmask]
Subject: [SPM] fFRI: First Level Analysis: Microtime Onset for Interleaved Scan
Dear colleagues,
I am analyzing fMR images acquired with an interleaved sequence of 34 slices.
The slices (indices corresponing to order along z-axis) were acquired in the following time order:
[18 1 19 2 20 3 21 4 22 5 23 6 24 7 25 8 26 9 27 10 28 11 29 12 30 13 31 14 32 15 33 16 34 17]
Slice 18 was acquired at TR/2.
I performed slice time correction using slice 18 as reference slice (inputs for slice order and reference slice in ms), followed by realignment, normalization, (optional filtering - wavelet toolbox), and smoothing.
As I want to perform first level analysis, I am uncertain about the slice number to be entered as microtime onset, more specifically whether it should be 1 or 18 to match TR/2?
Thank you!
Kind regards,
Peter
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