ARKHANGELSK, May 12. /TASS/. Scientists of the Laverov Federal Research Center for Integrated Arctic Studies (the Russian Academy of Sciences' Urals Branch) determined how the Earth's magnetic field affects heart functions, Lilia Poskotinova, head of the Biorhythm Laboratory, told TASS. This parameter is the baroreceptor reflex, responsible for blood pressure and pulse rate. In people with high blood pressure, the magnetic field fluctuations cause the heart tension.

"In people with arterial hypertension, we have seen a fairly pronounced synchronization of magnetic field and cardiac activity indicators, though there was practically no synchronization of fluctuations in the baroreflex indicator. That is, in those people, the cardiac activity tension increased with changes in the magnetic field, unlike in people with regular blood pressure. An increase in this trend means a certain risk of a hypertensive reaction to geomagnetic disturbances," the scientist said.

Scientists have not reached consensus about by which organs, systems, or tissues the human body may respond to the magnetic field fluctuations. Noteworthy, the magnetic field disturbances may be significantly pronounced in the high-latitude Arctic. "We live in high latitudes, this is very important for us. Our task is to find subtle mechanisms that are still unknown. For example, birds have certain cells in the brain base area, and they respond to the magnetic field changes, and fish also have certain sensors," she added.

Some researchers say people without health problems or without pronounced psycho-emotional disorders do not notice geomagnetic fluctuations. However, many scientific publications reflect the sensitivity of human regulatory systems to the geomagnetic field variations. They are seen at the population level, where severe health deteriorations happen during geomagnetic fluctuations.

The center's scientists examined people with both regular and high blood pressure. In the project, scientists used data from the Russian Academy of Sciences' Klimovskaya geomagnetic observatory.

The researchers analyzed minute variations in the magnetic field that regularly occur due to the ionosphere currents. "We measure the heart variability for 30 minutes to see what magnetic activity was at that time, and then we check the synchronization indicators," the scientist said. "Whenever this indicator is synchronized, we say the reserve is good. If not, there are certain risks of weather dependence."

Baroreflex and its response to magnetic disturbances

The center's specialists found that in people with regular blood pressure, heart rate variations are not related to the magnetic field variations, and only the baroreflex reacted to those changes as it turned out to be synchronized with them. People need baroreflex to prevent excessive rise and fall of blood pressure from stressful factors. Baroreflex synchronized with the geomagnetic field changes provides the human body with moderate fluctuations in pulse rate and blood pressure. Thus, a healthy person normally is resistant to geomagnetic disturbances and does not notice them.

On the other hand, this mechanism is poorly expressed in people with arterial hypertension. "In magnetic disturbances, they may experience "strained" stress index and a decrease in mechanisms that resist the heart stress and that are regulated by the vagus nerve," the scientists said.

The method to determine the heart rate baroreflective regulation sensitivity to the local geomagnetic field variations, developed by Arkhangelsk scientists was patented along with Yuri Semenov, the developer of the Varikard device, and Tatiana Zenchenko of the Institute of Theoretical and Experimental Biophysics (the Russian Academy of Sciences) and the Space Research Institute (the Russian Academy of Sciences).