Dear SPM
I am trying to specify a model to examine a group of 7 controls that were scanned at 3 time points (using fMRI). I am trying to determine whether the regression slopes of the individual controls are different from zero. I would also like to estimate the mean activation over the 3 time points per patient.
I have the individual contrast images (21 in total) and am using the PET models box. I can calculate the group regression slope across time points (I can also do this with Basic Models in fMRI). However I cannot seem to specify a model with the subjects in a separable fashion which lets me get at the individual regression slopes and means. This is because I keep getting errors:
If I try the single subject: Condtions and covariates option I get the following error after entering the data as 21 conditions:
??? Error while evaluating uicontrol Callback.
>> ??? Error using ==> spm_spm_ui
unestimable condition effects
If I try the multi-subj: cond x subj interactiona and covariates, and enter the 7 subjects and 3 conditions, I get the following error:
??? Error using ==> spm_spm_ui
unestimable condition effects
??? Error using ==> pause
Error while evaluating uicontrol Callback.
??? Error while evaluating uicontrol Callback.
>> ??? Error using ==> set
Invalid handle.
Error in ==> /local/SPM99/spm_input_ui.m
On line 850 ==> set(h,'Style','Edit',...
Error in ==> /local/SPM99/spm_input.m
On line 65 ==> [varargout{:}] = spm_input_ui(varargin{:});
Error in ==> /local/SPM99/spm_spm_ui.m
On line 1496 ==> ti2 = spm_input([str,' ',DsF{2},'?'],GUIpos2,'c',ti2',n21,Dn(2));
Error in ==> /local/SPM99/spm_spm_ui.m
On line 802 ==> [P,I] = spm_spm_ui('Files&Indices',D.sF,D.n,D.b.aTime,nVar);
Is there a problem with the way I am specifying the models or is it something else?
Thanks
Ahmed Toosy
