A system for measuring an electrophysiological (EP) signal of a subject, e.g., while the subject is in an MRI bore, includes antennas and circuitry to measure the EP signal； detect, using the antennas, magnetic-field changes due to MR operation； and isolate the EP measurement from resulting electrical transients. A control unit operates the detection circuitry to measure the EP signal at a time other than during the magnetic-field changes. A communication module transmits the EP signal via at least one of the one or more antennas. Some examples include a reference electrode to contact the body of a subject； a differential-pair to transmit a reference signal； and a converter at a measurement electrode to reconstruct the reference signal from the differential pair. Some examples provide an electrical or electromagnetic (e.g., optical) stimulus to tissues of a subject during a quiescent, non-readout MR period.
