Surface coil impact on rsfMRI?

Dear all,

I am using a brain surface coil to do some resting state fMRI experiments. As a result, the signal I'm getting isn't homogeneous - the images being brighter/having more signal at the surface of the brain than basally.

I am new to the resting state field and I am therefore unsure how the signal inhomogeneity resulting from using the surface coil might affect my data. Would you think that the difference in signal intensity across the brain would induce some spurious correlations?

Thank you for your help,