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Hi, I have a within subjects, placebo controlled IV infusion pharmacological fmri study. Subjects will be scanned on two occasions. I have seen a few papers that have analysed pharmacological fmri studies (i.e. fmri with IV infusion) using a psuedo-block design. In this approach each scan is divided into blocks (e.g. 1min in length) and the pre-infusion block is used as a baseline. At the first level this would give N-contrasts (block 1 - baseline, block 2 - baseline .......) per individual. What would be the most robust way to analyse these data? I could just use a paired sample t-test but that does not seem appropriate as I would not (neccessarily) be correcting for the number of contrasts. Are there more robust alternatives? Alternatively, could one use ICA to identify a pharmacological regressor (I am not collecting blood samples or any other surrogate marker of drug pharmacokinetics but I know from previous studies the approximate shape and time course of the drug) and then use this pharmacoregressor at the first level - giving one contrast per individual? My concerns are that I would be guessing on the time course (although an educated guess as I could examine the time course in a region I know to be rich in the receptor of interest) and that this seems circular? Would it be better to pilot this approach in a small number of subjects and generate an average pharmacoregressor? Thanks