Biomagnetic signals of the human body

Magnetic field of the heart (different perspectives) The impulse for the human heart to beat starts from a place directly on the upper heart, the sinus node. Here the heart beat is excited. When the excitation is further transmitted in the myocardium, a measurable current flows. As soon as the myocardium contracts for the heart beat, the cells return to their initial state, and the play begins again. The conduction of nervous stimuli and the muscular activity are also accompanied by electrical processes. These processes are today still routinely detected by ECG measurements which cover the voltage on the body surface. A more direct access to the electrophysical processes in the body is provided by biomagnetic investigations. They use highly sensitive sensors to detect the magnetic fields emanating from the body. Admittedly these signals are extremely weak and can be sensed even by the highly sensitive magnetic field sensors (SQUIDs) only if any influences which might be exerted by the environment which is full of magnetic signals are precluded. Comparable difficulties would be encountered by a lepidopterist who would want to record the soft flapping of the wings of his darlings next to starting jet planes!