rTMS is using electromagnetic fields to influence the brain,on this video you can see magnetic fields although not related to rTMS. The comment is very technical but the video is amazing, even scary.
From: Environmental graffiti
Combining their scientific experience with artistic instinct in sound, animation and programming they have created a ‘magnetic magnum opus’ - a ‘tour de force’ of immense invisible force brought down to human scale. And it is precisely the meeting of scale that makes the work so fascinating - to think that these tiny pulsating currents surround our planet on a scale inconceivable to man is not only a humbling thought, but an uplifting one. The inherent beauty of nature is again, in Wordswoth’s words, too much with us.