Simultaneous Electrophysiology and Functional Magnetic Resonance Imaging Studies in Conscious Rats

Abstract

This chapter discusses the simultaneous electrophysiology and functional magnetic resonance imaging (fMRI) studies in conscious rats. fMRI is a noninvasive procedure for studying the localization of the brain activity and measures the local changes in cerebral hemodynamics. fMRI acquisitions are correlated with spontaneous electrophysiological events, and thus help identify the generators of these events. The evaluation of artifacts due to random motion of the animal during MR data acquisition and between different sampling/acquisitions over a period of time was carried out. It is observed that once the rats are trained successfully, simultaneous electrophysiology and fMRI experiments can be carried out during sleep–wakefulness. The various steps undertaken in order to carry out simultaneous electrophysiological and MRI recordings in the rat brain are explained. It is found that simultaneous electrophysiological recordings and fMRI provide a unique method to study the brain state with good spatial and temporal resolution, but such studies are associated with a number of technical limitations.