Statistical inference based on fMRI data alone can only draw conclusions about regional hemodynamic effects. However, it is the neuronal effect that is of ultimate interest to neuroimaging. Interpretations of BOLD fMRI data in terms of neural responses are crucially dependent upon the neurovascular coupling, which is commonly referred to as the relationship between electrophysiological responses and BOLD signals. This relationship should also serve as the most fundamental ground for all fMRI-EEG/MEG integrated neuroimaging methods (to be discussed later).
