Migratory birds depend on Earth's magnetic field to navigate, and now there is evidence that humans may be unconsciously in touch with it as well, research shows.
"It appears humans are subconsciously sensing geomagnetism," said Ayumu Matani, a University of Tokyo associate professor of cognitive neuro-engineering and one of the team's researchers. "Earth's magnetic field may be influencing human behavior in some way or other."
The researchers from the University of Tokyo, California Institute of Technology and elsewhere, said March 19 that when they altered the magnetic field in the room a test subject was sitting still in, the person's brain waves were tricked into thinking the person had changed the direction they were facing, when in fact they had not moved.
Apart from birds of passage, many other species, such as honeybees and salmon, are known to be able to sense the geomagnetic field. A number of experiments had been conducted on humans as well to test if they perceive it, but had so far yielded inconclusive results.
During the latest study, the team had 34 volunteers consisting of men and women from Japan and the United States sit with their eyes closed in a dark, quiet experimental chamber shielded from external electromagnetic waves by metal walls. The chamber was wrapped with coils, which were used to stimulate the subjects magnetically.
Responses were detected in the "alpha waves" of their brains when the magnetic field in the chamber was altered as if the subjects had turned from facing northeast to facing northwest.
The research team announced their results in an article published in the U.S. neuroscience journal eNeuro.