Exploring interregional brain interactivity in temporal lobe epilepsy using partial correlation analysis of fMRI data.

Simultaneous recording of functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) has been recently used to measure metabolic changes related to interictal spikes in temporal lobe epilepsy (TLE). Since blood oxygen level dependent (BOLD) responses have been often observed in extratemporal regions, we propose to explore interregional brain connectivity using a data-driven method based on partial correlation analysis of fMRI data. This approach allows to extract informations about functional interactivity and to differentiate direct from mediated interactions. We demonstrated that this technique provides a deeper insight into the functional relationships between the areas involved in the generation of spikes in TLE.