Many animals, such as migratory birds, are aware of the Earth’s magnetic field. Researchers from California have conducted experiments that demonstrate magnetic reception in humans: Our brain will unconsciously detect the Earth’s magnetic field.
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Early natural science books taught us that the human body has five senses: sight, hearing, touch, taste, andSmell. For a very long time, the question has been about the existence of a human sixth sense, allowing perception magnetic field, Debate.
So far, the experiments conducted have not convinced the scientific community. On site Conversation, The authors of this new paper explain that these failures were due to The fact that nearly all previous studies relied on participants’ behavioral decisions. If humans have a magnetic sense, then everyday experience indicates that it is very weak or profoundly unconscious. ” This is why researchers at Caltech Institute of Technology (California) wanted to capture subconscious reactions to brain.
Although low in intensity, this magnetic field is perceived by different animals that use it to find their directions. plenty Vertebrates Response to magnetic stimuli: PiscesAnd the AmphibiansAnd the ReptilesAnd the birds and between Mammals, Whales, RodentsAnd the BatsAnd the CowsAnd the dog… in the microbial world as well, bacteria It has crystals Black iron oxide It is one of the types of compasses that allow the cell to swim according to magnetic field lines. The Black iron oxide It is found in many animals, including the human brain. Hence the question that everyone raises: Does a person have a magnetic sense?
To answer this fundamental question, researchers A. Faraday cage They can apply a magnetic field thanks to the large coils. The created magnetic field, with an intensity of 35 µT (microTesla), can be directed in different directions. In comparison, in France, the Earth’s magnetic field On the order of 45 µT.
Humans have a geomagnetic sense
To find out the electrical activity of the 34 participants’ brains, the researchers ran EEG. During the experiment, each participant was required to remain seated in a chair in this room, isolated from the external radio frequencies, for 7 minutes, at I close my eyesWhile the researchers alter the magnetic field. The field can rotate clockwise or counterclockwise, as if you were moving your head left or right, and facing downward, tilted 60 degrees from the horizontal, such as magnetic field My land latitudes From Pasadena, California.
The participants didn’t feel anything in particular when the magnetic field was manipulated, but their brains seemed to react. Researchers have observed in some people that when the magnetic field, directed downward, rotates counterclockwise, the amplitude of the alpha waves decreases a lot. Alpha waves from A. Frequency Of 10 HzWe control the EEG when we’re awake, but with our eyes closed, that is, in a relaxed state. When Stimulus Suddenly a rhythm appears Alpha waves Asynchronous, low in capacitance. This phenomenon, called alpha-event-related cancellation, or alpha-ERD in English, can occur, for example, when the brain perceives flash Luminous. Alpha-ERD means the brain has picked up Stimulus It handles the information.
We have a sensory system that processes the geomagnetic field all around us
So these experiments indicate that the human brain is discovering the Earth’s magnetic field. according to Agency press releaseAnd the “We have a sensory system that processes the geomagnetic field all around us.” Then a new question arises: What is the use of this geomagnetic meaning in humans? Perhaps our ancestors Hunters Do they use them to guide themselves and stay alive.
In the experiment, there were some differences between the participants: some barely reacted, while others had a half-dip in alpha waves after the magnetic change. So humans will have a variable geomagnetic sensitivity from one person to another.
What to remember
- The existence of a magnetic sense in humans is controversial.
- Many animals are sensitive to Earth’s magnetic field.
- Researchers from California studied the brain waves of people who were placed in a room where they altered a magnetic field.
- The brain responded to changes in the magnetic field.
The scientist says that man is aware of magnetic fields
Article was published on June 28, 2016
According to Joe Kirchvink of the California Institute of Technology, humans have a sixth sense that allows them to discover the Earth’s magnetic field. This ability has already been identified in birds and is suspected in mammals. In humans, the hypothesis has been mentioned but without concrete evidence.
the birds InsectsAnd mammals … many animals seem to have it Magnetic sense. So why not a man? The the birdsHe, of course, used it to orient themselves during their migrations. But it has also been proven in mammals: for example, rats Wood Mole rats use magnetic field lines to build their nests. In the pastures Cattle It appeared in one study to orient themselves along these lines, and dogs may be in a north-south position when they relieve themselves.
Two hypotheses can be explained Magnetism With animals. The first is that Earth’s magnetic field Effect protein call Cryptochromes, Found in Retina Birds, dogs, and even humans. The second hypothesis is that there are receptor cells in the body that contain small compasses made of a Mineral Magnetic: magnetite. They will orient themselves according to the Earth’s magnetic field. Magnetite is found in cells Peck Birds.
This is the preferred premise Joe Kirchvink, From Caltech (California Institute of Technology), who specializes in biomagnetism but also in Ancient magnetism. This researcher is famous for being an inventor. Snow globe In 1992, in fact, he confirmed it Glaciers It covered the entire world more than 650 million years ago. they Source Was preferredCambrienne blast 540 million years ago.
A magnetic field in a Faraday cage
Previous work had already attempted to demonstrate the existence of a magnetic sense in humans, but it was not reproducible. On the other hand, those of Joe Kirchwink are just as well, he says. Last April, he presented his results to a conference Royal Institute of Navigation, in the UK. Confirm this Humans have functional magnetic receptors.. This finding is also described in the review Science Magazine.
The study involved involved 24 subjects and was the subject of only one contact; It has not been published in a peer-reviewed journal. The experiment began in 2014 with Joe Kirschvink himself, and he used the large Faraday cage, which is a box made of Aluminium Protect the electromagnetic environment. Guinea Pigs sit in a cage, in the dark, and are exposed to a pure, uniform magnetic field, without any other field. confusionNor the motivation. Participants wore Sensors On Skull To perform the EEG, in order to follow Brain activity. Researchers can change the direction of the magnetic field.
During this study, many tests were carried out; In some, a strong magnetic field is like a field Ter Slowly spin around the participants’ heads. When the magnetic field rotated counterclockwise, the participants’ alpha waves decreased. to nervous cells So it seemed to respond to the magnetic field. In addition, the neural response occurred after a slight delay (a few hundred thousandths of a second), indicating an active brain response, according to the researcher. For now, the results stop there, but the researcher promises that other laboratories, in Japan and New Zealand, will try to confirm his results.
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