Here's a 1992 paper, "Magnetite biomineralization in the human brain": < http://www.ncbi.nlm.nih.gov/pmc/articles/PMC49775/ >, from the Proceedings of the National Academy of Sciences.

From the abstract: << Although the mineral magnetite (Fe3O4) is precipitated biochemically by bacteria, protists, and a variety of animals, it has not been documented previously in human tissue. Using an ultrasensitive superconducting magnetometer in a clean-lab environment, we have detected the presence of ferromagnetic material in a variety of tissues from the human brain.

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--Dan ------------- Veit wrote: << I wrote: << Apparently the presence of magnetite has recently been confirmed in human brains.

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References? I found a paper reporting magnetite in sinus bones -- not within the actual brain. It's not clear how magnetic torques would be detected by neurons or glial cells.

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_____________________________________________________________________ "It don't mean a thing if it ain't got that certain je ne sais quoi." --Peter Schickele