If Anxiety is in my Brain, why is my Heart Pounding? A Psychiatrist Explains the Neuroscience and Physiology of Fear

When faced with a perceived threat, your body often activates a fight or flight response. Heart in your throat. Butterflies in the stomach. Bad feeling. These are all phrases that many people use to describe fear and anxiety. You’ve probably felt anxiety in your chest or stomach, and your brain usually doesn’t hurt when you’re afraid. Many cultures link cowardice and bravery more to the heart or the guts than to the brain.

But science has traditionally viewed the brain as the birthplace and processing of fear and anxiety. So why and how do you feel these emotions in other parts of your body?

I am a psychiatrist and neuroscientist that investigates and treats fear and anxiety. In my book”Scared,” I explain how fear works in the brain and body and what effect too much anxiety has on the body. Research confirms that, although emotions originate in the brain, it is the body that executes the orders.

Fear and the brain

While your brain evolved to save you from a falling rock or a speeding predator, the anxieties of modern life are often much more abstract. Fifty thousand years ago, being rejected by your tribe could mean death, but failing to do a great job in a public speech at school or at work doesn’t have the same consequences. Your brain, however, You may not know the difference.

There are some key areas of the brain that are heavily involved in fear processing.

When you perceive something as dangerous, whether it’s a gun pointed at you or a group of people looking at you sadly, these sensory inputs are first transmitted to the amygdala. This small, almond-shaped area of ​​the brain located near the ears detects the emotional salience or relevance of a situation and how to react to it. When you see something, determine whether you should eat it, attack it, run away from it, or have sex with it.

Threat detection It is a vital part of this process and it has to be quick. Early humans didn’t have much time to think when a lion lunged at them. They had to act quickly. For this reason, the amygdala evolved to bypass areas of the brain involved in logical thinking and can directly involve physical responses. For example, seeing an angry face on a computer screen can immediately trigger a detectable amygdala response without the viewer even being aware of this reaction.

the hippocampus It is close and closely connected to the amygdala. It involves memorizing what is safe and what is dangerous, especially in relation to the environment: it puts fear into context. For example, seeing an angry lion at the zoo and in the Sahara triggers a fear response in the amygdala. But the hippocampus intervenes and blocks this response when you are at the zoo because you are not in danger.

He prefrontal cortex, located above the eyes, is primarily involved in the cognitive and social aspects of fear processing. For example, you may be afraid of a snake until you read a sign that the snake is not poisonous or the owner tells you that it is his friendly pet.

Although the prefrontal cortex is often considered the part of the brain that regulates emotions, it can also teach you fear based on your social environment. For example, he may feel neutral going into a meeting with his boss, but immediately feel nervous when a colleague tells him about rumors of layoffs. Many prejudices such as racism they are rooted in learning fear through tribalism.

Fear and the rest of the body.

If your brain decides that a fear response is warranted in a particular situation, it triggers a cascade of neural and hormonal pathways to prepare for immediate action. Part of the fight or flight response, such as heightened attention and threat detection, takes place in the brain. But the body is where most of the action happens.

Various pathways prepare different body systems for intense physical action. He motor cortex The brain sends quick signals to the muscles to prepare them for quick, forceful movements. These include muscles in the chest and stomach that help protect vital organs in those areas. That could contribute to a feeling of tightness in the chest and stomach under stressful conditions.

He sympathetic nervous system It is the accelerator pedal that accelerates the systems involved in fight or flight. Sympathetic neurons are distributed throughout the body and are especially dense in places such as the heart, lungs, and intestines. These neurons cause the adrenal gland to release hormones such as adrenaline that travel through the blood to reach those organs and increase the rate at which they experience the fear response.

To ensure a sufficient supply of blood to the muscles when they are in high demand, signals from the sympathetic nervous system increase the rate of the heartbeat and the force with which it contracts. You feel both an increased heart rate and a contracting force in your chest, so you can connect the feeling of intense emotions to your heart.

In the lungs, signals from the sympathetic nervous system dilate the airways and often increase the rate and depth of breathing. Sometimes this results in a feeling of difficulty breathing.

Since digestion is the last priority during a fight or flight situation, sympathetic activation slows down the intestine and reduces blood flow to the stomach to save oxygen and nutrients for more vital organs like the heart and brain. These changes in your gastrointestinal system may be perceived as discomfort related to fear and anxiety.

It all goes back to the brain

All bodily sensations, including visceral sensations from the chest and stomach, are transmitted to the brain through the pathways. through the spinal cord. His brain, already anxious and highly alert, processes these signals on both a conscious and unconscious level.

the island It is a part of the brain specifically involved in awareness of your emotions, pain, and bodily sensations. He prefrontal cortex It also engages in self-awareness, especially by labeling and naming these physical sensations, such as feeling tightness or pain in the stomach, and attributing cognitive value to them, such as “this is fine and it will go away” or “this is terrible and I’m not.” dying.” These physical sensations can sometimes create a cycle of increasing anxiety as they make the brain feel more fearful of the situation due to the agitation it feels in the body.

Although feelings of fear and anxiety begin in your brain, you also feel them in your body because your brain alters your bodily functions. Emotions take place in both your body and your brain, but you become aware of their existence in your brain. As rapper Eminem recounted in his song “Lose Yourself,” the reason his palms were sweaty, his knees weak, and his arms heavy was because his brain was nervous.

Arash JavanbakhtAssociate Professor of Psychiatry, Wayne State University

This article is republished from The conversation under a Creative Commons license. Read the Original article.