Dear SPM Experts
I am new to spm and have three questions about source reconstruction.
1.
As the manual say, user can choose the time and frequency window that will be available for inversion. After that when pressing 'window' button for create contrast image, another time-frequency window need inputs. My question is "What's the relationship between the two time frequency windows ? Does the latter have to be the subset of the former one ?".
2.
I feel puzzled about “contrast image” . Contrast what? I think there are at least two objects in a contrast (A-B,for example). What the "A"and "B" here? experimental conditions? Or “contrast image” just describes summary measures of one subject ?
3.
I notice that input data file can be either epoched or averaged. So, if i care about the evoked response, i have two choices to process data:
(1).input data is epoched, and choose 'evoked' among {'evoked','induced','trials'}
(2).input data is averaged.
what is the difference between the two choices?
Thanks for you patience!!
sincerely
Liang zhou
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