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Dear list, I’m responding to a reviewer’s feedback, and they asked an astute question about the upsampling of fMRI data during normalization. I up-sampled my data from a non-isotropic voxel size (2.15x2.15x7mm) to be isotropic 2x2x2mm (the same as the target brain template). I’ve been asked to consider the effects of this on contrast statistics, and I’m unsure of them. My impression would be that upsampling the data would artificially increase the number of voxels, and therefore the number of contrasts, so that 1. for uncorrected p values, more between-condition significant differences will be identified. 2. for corrected p values, the correction is calculated using the number of independent components in the data (GRF theory) which will remain constant in spite of upsampling, so that more between-condition significant differences will be identified. Is this correct? Am I off track? I’d be grateful for any advice. Thanks – Christopher