Abstract: A method for collecting and a device for sensing at least one electrophysiological signal, as well as to a system including at least one such device. The device for sensing at least one electrophysiological signal from a living subject subjected to at least one electromagnetic field, includes elements, such as electrodes, which are placed on the subject for the physical acquisition of at least one electrophysiological signal and at least elements for the pre-processing of the at least one sampled electrophysiological signal. The sensor device (1) is characterised in that it also includes additional elements (7, 8) for measuring or determining at least one characteristic of the electromagnetic environment at or close to the electrophysiological signal acquisition point(s) or zone(s) on the subject.