Dear SPM list,
I am having a problem specifying a design for an fMRI event-related learning
task. There are 10 similar items that repeat 5times each during the scan.
Repeat delays are constant but the initial presentation of items is somewhat
spread-out and variable over the scan.
This is a fixed-effect, single subject analysis. The subject has two scans
with equivalent alternate forms.
I tried to model this as 10 trial-types, variable SOA. TR=3, looking at the
linear interaction with time only. After I enter a vector of onset times (in
TRs) for each trial-type I get the following error:
SPM99b: spm_fMRI_design (v2.16) 09:52:01 - 29/11/1999
----------------------------------------------------------------
??? Error while evaluating uicontrol Callback.
>> ??? Index exceeds matrix dimensions.
Error in ==> /usr/local/spm99b/spm_fMRI_design.m
On line 220 ==> pst = [1:k]*RT - on(1);
Error in ==> /usr/local/spm99b/spm_fmri_spm_ui.m
On line 193 ==> [xX,Sess] = spm_fMRI_design;
Any insights or alternative ways of modeling this would be greatly
appreciated.
Sterling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sterling C. Johnson, Ph.D.
Neuropsychology Laboratory
Barrow Neurological Institute
222 W. Thomas Rd. Suite 315
Phoenix AZ 85013
email: [log in to unmask]
ph (602) 406-6704
fax (602) 406-6115
pager: (602) 746-9461
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