Geomagnetic fields interfere with the accumulation of iron in the human brain. Magnetic sensing of the human brain provides compelling evidence of new electric mechanisms in human brains and may interfere with the evolution of neurodegenerative diseases. We revealed that the human brain may have a unique susceptibility to conduct electric currents as feedback of magnetic dipole fluctuation in superparamagnetic grains. These grains accumulate and grow with brain aging. The electric feedback creates an electronic noise background that depends on geomagnetic field intensity and may compromise functional stability of the human brain, while induced currents are spontaneously generated near superparamagnetic grains. Grain growth due to an increase of iron mobility resulted in magnetic remanence enhancement during the final years of the studied brains.

1st Faculty of Medicine Institute of Forensic Medicine and Toxicology Charles University and General Teaching Hospital Studničkova 4 128 00 Prague 2 Czech Republic

Geophysical Institute University of Alaska Fairbanks 903 N Koyukuk Drive Fairbanks AK USA

Institute of Hydrogeology Engineering Geology and Applied Geophysics Faculty of Science Charles University Albertov 6 120 00 Prague 2 Czech Republic

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