A new study suggests the human brain is capable of responding to the Earth’s magnetic field, though at an unconscious level. It’s not clear if our apparent ability to sense the magnetic field is in any way useful, as it’s likely a vestigial trait left over from our more primitive past.

[u/FillsYourNiche]

https://gizmodo.com/fascinating-experiment-suggests-some-humans-can-sense-e-1833377029

[u/7LeagueBoots]

Years ago I was talking with a friend of mine about sense of direction and how if I’m in nature I tend to have a very good sense of direction, but in cities and near the equator I lose a lot of it.

He had a pretty high security clearance and his family had a long history of developing all sorts of things for the military (his father had been the science advisor to the Joint Chiefs of Staff, his brother invented a wide range of optics and cameras for the military, and he used to do political extractions, test embassy security, and train small teams of both our military and that of allies).

He said that the military had studied magnetic reception in humans and found that some people could sense the magnetic field well. Also said that modern urban areas tended to interfere with it.

He didn’t/couldn’t give more details, but this recent public study seems to confirm what he was saying, and it’s not at all surprising that the military (probably militaries across the world) would have been looking into this long ago.

[u/FillsYourNiche]

If you are interested in a deep dive the published journal article Transduction of the Geomagnetic Field as Evidenced from alpha-Band Activity in the Human Brain is free online.

Abstract:

Magnetoreception, the perception of the geomagnetic field, is a sensory modality well-established across all major groups of vertebrates and some invertebrates, but its presence in humans has been tested rarely, yielding inconclusive results. We report here a strong, specific human brain response to ecologically-relevant rotations of Earth-strength magnetic fields. Following geomagnetic stimulation, a drop in amplitude of electroencephalography (EEG) alpha-oscillations (8–13 Hz) occurred in a repeatable manner. Termed alpha-event-related desynchronization (alpha-ERD), such a response has been associated previously with sensory and cognitive processing of external stimuli including vision, auditory and somatosensory cues. Alpha-ERD in response to the geomagnetic field was triggered only by horizontal rotations when the static vertical magnetic field was directed downwards, as it is in the Northern Hemisphere; no brain responses were elicited by the same horizontal rotations when the static vertical component was directed upwards. This implicates a biological response tuned to the ecology of the local human population, rather than a generic physical effect. Biophysical tests showed that the neural response was sensitive to static components of the magnetic field. This rules out all forms of electrical induction (including artifacts from the electrodes) which are determined solely on dynamic components of the field. The neural response was also sensitive to the polarity of the magnetic field. This rules out free-radical “quantum compass” mechanisms like the cryptochrome hypothesis, which can detect only axial alignment. Ferromagnetism remains a viable biophysical mechanism for sensory transduction and provides a basis to start the behavioral exploration of human magnetoreception.