Combined measurement of event-related potentials (ERPs) and fMRI.

The study investigates the possibility of combined recording event-related potentials (ERPs) and functional MRI (fMRI). Visual evoked potentials (VEPs) were elicited by an alternating black and white checkerboard, which was presented blockwise outside the static 1.5 T magnetic field and during an echo planar imaging (EPI). An fMRI sequence with a time window for interleaved EEG-measurement and a measurement protocol which reduces pulse artifacts and vibrations was used. Thus, during an EPI sequence, it was possible to detect VEPs which had the same structure and latencies as VEPs outside the magnetic field and which corresponded well with the observed activated areas of the visual cortex.