We encountered the problem that our surface coil array seems to receive more signal from the left hemisphere than from the right. This results in an SNR decrease of about 20% in the right hemisphere.
Consequently, the activations that appear in the statistical maps are strongly biased towards the left hemisphere. When looking at the voxel time courses we clearly see the activation of our sensory stimulation in the right sensory cortex, however due to the increased noise it does not show up on the t-maps.
Is there a way to correct post-hoc for inhomogeneities in the sensitivity, in order to make unbiased comparisons across hemispheres?
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