I don't think it is necessarily the case that you have to have intense magnetic fields to alter brain function. Have you come across this area of medical research called picotesla magnetic fields? These ultra weak magnetic fields certainly alter brain function, as numerous studies have shown. Picotesla magnetic fields have been used to experimentally treat diseases like Parkinson's. Refs: 1, 2. As the name suggest, picotesla magnetic fields have an intensity around 10^-12 Telsa (the metric prefix pico signifies 10^-12). By comparison, the Earth's magnetic field is around 10^-5 Telsa, and a fridge magnet is around 10^-2 Telsa (0.01 Telsa). This means picotesla magnetic fields are around 10 million times weaker than the Earth's magnetic field. Yet they affect brain function, and can ameliorate certain neurological diseases like Parkinson's. You can also use picotesla magnetic fields with frequencies that match the alpha or theta brainwave frequencies to induce spiritual effects in the brain. I can vouch for this effect myself, as years ago, before I got ME/CFS, I built my own picotesla magnetic field generator (easy to build if you know something about electronics), and when I applied alpha or theta brainwave frequencies to myself, I developed a strong spiritual meditative state, very similar to the one you get after doing several hours of mindfulness meditation (which I have experience of). The frequency of an oscillating magnetic fields is just as important as the power level. Tectonic Strain Theory of Visitations Oscillating magnetic fields can be generated at tectonic plate fault lines on the Earth: the pressure on the rocks beneath can cause an electric current to flow, via the piezoelectric effect, and this electric current in turn can generate oscillating magnetic fields. There is a theory by Dr Michael Persinger that visitations (whether visitations by the Virgin Mary in times past, or in modern times, by aliens/UFO's, etc) are triggered by the effect of oscillating magnetic fields at seismic fault lines and tectonic plates. This theory is known as the Tectonic Strain Theory. Tectonic Strain Theory References: Michael Persinger - Wikipedia Tectonic Strain Theory by Michael A. Peringer I am not arguing that mystical, spiritual and paranormal experiences can all be explained away by such theories. Even if it is true that oscillating magnetic fields trigger the brain to have these experiences, which I suspect it is, that does not mean that all experiences are invalidated. The magnetic trigger may just bring out something already there in the brain, such as epilepsy, with the magnetic trigger just precipitating an ictal experience. Epileptics have historically been considered as spiritual "seers". It is also interesting that two areas of known high seismic activity, namely California and the Middle East, both are deeply steeped in spiritual and religious fervour: California is home to more zany religious cults than anywhere else in America; and the Middle East, though more conservative in its religious tastes, is equally as fanatic.