Influence of low magnetic-field-strength variations on the retina and pineal gland of quail and humans.

Recently, Schulten postulated on the basis of his experiments and quantum-mechanical calculations that variations of the strength of the earth's magnetic field may influence reactions in biological systems. In this paper groups of birds were subjected to different variations of low magnetic-field strength. The influence of these variations on the enzyme hydroxyindol-O-methyl transferase (HIOMT) was determined. HIOMT is unique to the retina and the pineal gland and seems to be involved in regulation of light-adaptation processes. A significant effect was found, which can be interpreted as being in agreement with Schulten's theory. These observations were further supported by our examination of the influence of magnetic field variation on human night-vision acuity. Whereas the magnetic influence on the avian retina may be interpreted in connection with navigation, the importance for the human retina remains to be elucidated.