Conceptual question about the link between CBF and BOLD signal

Hi all,

I have the following conceptual/theoretical question about the interpretation of functional connectivity (FC) changes using resting-state fMRI data:
Imagine you have a paired design with resting-state fMRI data acquired before and after an intervention. We hypothesise this intervention induces neuroplasticity, which we want to detect through FC changes. However, it is likely that the intervention also causes CBF changes. If this is indeed the case, we assume this change in CBF is the same across the whole brain and is not regional specific. My question is then whether FC changes could be purely driven by the assumed CBF changes.

My first thought is that it wouldn’t. My reasoning for this is that changes in CBF would influence the BOLD signal amplitude, but not necessarily the BOLD signal changes in time (the time series itself) that correlate between regions/voxels, the latter being the definition of FC.

Is this reasoning correct or are there any other thoughts on this matter?

Thank you very much.