Dear SPMers;
I am running a case report which I would like to mapping the brain activation of one volunteer who took an hallucinogenic substance common in some regions here in Brazil. We acquired two SPECT images from this volunteer; one day before he/she had taken the substance (SPECT-PRE) and another one after he/she taken the substance (SPECT-POS).
For the first SPM analysis we ran:
1) We compared the SPECT-PRE versus 10 SPECT controls (using two sample T-Test).
2) We compared the SPECT-POS versus 10 SPECT controls (using two sample T-Test).
Now we would like run an analysis considering the pair of images (SPECT-PRE and SPECT-POS) in order to show the difference between both conditions in the same analysis (before and after take the substance)
In 2005, McNally et al published an article which it is presented the concept they named ISAS (Ictal-Interictal SPECT Analyzed by SPM) where they used the model Multi-groups: conditions and covariates to compare together the ictal and interictal SPECT of the patient (epilepsy) against pairs of SPECTS of the control group.
We would like to use similar concept in our study. Has anyone used something like this? Is there other model more suitable for this kind of analysis?
Thanks in advance.
Henrique Amaral
Ribeirao Preto Medical School
http://www.fmrp.usp.br/novo_portal/
University of Sao Paulo
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