The purpose of this application is to request funding to conduct pilot studies to develop a state-of-the-art 24-bit system for conducting electrophysiological recordings (visual evoked potentials - VEP, Local Field Potentials - LFP, Multi-Unit activity MU, Single-Unit activity SU) during functional MRI (fMRI). We currently have developed a complete 32-channel and 24-bit system for electrophysiological recording that has been extensively tested both at 3 T systems. Furthermore, we have already performed combined extracranial EEG-fMRI experiments at 3T and are technically able to perform intracranial LFP-fMRI experiments. Finally, we are currently able: (1) to perform state-of-the-art awake monkey fMRI experiments at 3""""""""1"""""""". We propose to upgrade the existing system to attain 30kS/s sampling per channel, and (2) develop software and MRI compatible intracranial electrodes. We will correlate the high-resolution awake monkey fMRI signals with the simultaneous recording of electrophysiological signals with a set of simple but interesting visual experiments to evaluate the quality of both the existing and the proposed systems. The final system for general electrophysiology during MRI will become a high impact tool for vision research, given the worldwide lack of commercially available MR-compatible systems for electrophysiological recording.
Purdon, Patrick L; Millan, Hernan; Fuller, Peter L et al. (2008) An open-source hardware and software system for acquisition and real-time processing of electrophysiology during high field MRI. J Neurosci Methods 175:165-86 |