How does Fear Begin
Fear takes hold of every one of us, and on these days, of security threats, it intensifies. What causes us to be afraid, what mechanism in the body creates the fear and why do we need it at all? You asked – our doctor replies.
Is an inseparable part of our lives. The reflex of fear is well illustrated on the baby as one of the innate reflexes. This feeling is maintained and intensified even during life. Yes, some of us are easily horrified, others are not really excited. So what creates the same fear, why do we need it, and what storms occur in the body during fear?
In fact, without fear we could not survive for long. Without hit we’d walk into a busy road, have casual sex without contraception or swim among sharks. Fear, as you probably understand, is necessary not only to scream in a nightmare film – it is necessary for the survival of humans and animals. During evolution those who were afraid of the right things were also those who managed to survive.
So how does fear begin? In the brain, of course. Once the threat is absorbed by the senses, it passes through different brain centers and forms a chain of reactions that we feel during it. The fear response operates on two cerebral pathways: the fast, immediate response, and the longer, longer path. Both paths operate at the same time, immediately upon the absorption of the alleged threat.
The goal of the fast lane is to make the body act immediately and “not take risks”. For example, if an explosion is heard in the south of the country, even if an alarm is not preceded, the immediate response is to flee for fear of a missile falling. In this way the body acts immediately to defend itself, and asks the questions afterwards. In the fast lane, three brain organelles begin to function: thalamus, amygdala, and hypothalamus.
When the sound of danger is heard (in our case, the explosion), the brain sends information to a cerebral neuron called a thalamus. At this point the thalamus does not know whether the signals it receives are dangerous signals or not, but since they may be transmitting the information to another organ called an amygdala, acting immediately to protect us. The amygdala (the amygdala) transfers to a third cerebral infarction, the hypothalamus, to act immediately, fight, or run away. We will return to this important slogan, fight or flight, of the brain.
Back to the fast lane, which operated the “fight or run” mechanism. As we mentioned earlier, the thalamus activated the amygdala that activated the hypothalamus. The latter active two systems: the sympathetic nervous system and the adrenal system. These two systems create the “fight or run” effect.
When the hypothalamus instructs the sympathetic nervous system to “shift gear”, the overall result is to accelerate activities in the body, simply to act quickly and instantly. Thus the body becomes very alert. The sympathetic system sends electrical signals to various glands in the body and muscles and controls the core of the adrenal glands above the kidneys to release adrenalin (epinephrine) and noradrenaline (norepinephrine) into the bloodstream. These are two stress hormones that cause many changes in the body, including the acceleration of heart rate and increased blood pressure.
At the same time the hypothalamus triggers the release of ACTH. This hormone enters the bloodstream, reaches the heart of the adrenal gland and activates 30 hormones waiting to deal with the threat.
The blood stream is now flooded with a variety of chemicals, neurotransmitters and hormones, including adrenalin and norepinephrine. All of these cause the following actions:
Heart rate increases: This allows blood to flow with oxygen to the organs of the body essential for war or escape from the frightening factor.
Blood pressure increases: This allows increased blood flow to the body’s organs.
The pupils are dilated: the more light rays penetrate the retina, the better the details around.
The veins in the skin contract: thus avoiding “waste” of blood flow to less vital areas and there is more blood flow to more important areas, such as the brain. Therefore, during fear, there is a feeling of chill and cold, because less blood flows into the skin.
The blood glucose level rises: so there is a high availability of carbohydrates for the energy expenditure of the body.
Sickly muscle muscles: These are different internal muscles. This allows more oxygen to reach vital organs, such as the lungs.
Non-urgent systems are silent: For example, the digestive system goes through a kind of “silence” to save energy for more important systems.
The brain has trouble performing small, delicate tasks. When fearing the brain, it focuses only on the “broad picture” to determine where the threat comes from and how to deal with it.
All these fear responses are meant to help us survive in dangerous situations under the same slogan: fight or run away. In this way, the body can fight the threat or escape. So the next time the fear attacks you let the body do its part for a while. It probably knows very well what is good for you.