You can’t make the world less frightening. But you can make yourself less fearful.

You can’t make the world less frightening. But you can make yourself less fearful.

You can’t make the world less frightening. But you can make yourself less fearful.

 

There’s no denying that the world is a scary place. Everyone has been frightened at some time in their lives. But some people are frightened more often or more intensely than their circumstances would explain. Some people even live in a state of fear. 

 

What part of the brain causes you to experience fear? Why does fear become pathological in some cases? And, if fear starts to take over your life, what can you do about it?

 

Fear emanates from the limbic system:

 

Initially conceptualized by Broca in 1878 and elucidated by Papez in 1937, neuroscientists understand the limbic system to be the interconnected brain regions that control our emotions, including fear. There is no universal agreement regarding the exact brain regions that comprise the limbic system, but most researchers include the cingulate cortex (communicates between emotional parts of brain and thinking/action/sensory parts of brain ), the hippocampus (controls emotion, memory, learning and navigation), the amygdala (controls emotion, memory and contributes to decision making), the septal nuclei (reward and play centers of brain) and the hypothalamus (controls body homeostasis and controls body hormone output for the four Fs: fight, flight, feeding and fornication).

 

Some fears are innate, they seem to be built into our DNA. For example, a certain percentage of people are frightened by spiders and snakes. A 2017 study by European scientists provided evidence that these fears are hard wired into the human brain. The scientists measured fear related pupillary dilation in infants. The babies sat on their mothers’ laps and looked at pictures of creatures they had never before seen. The physiologic fear reaction only occurred upon viewing pictures of spiders or snakes. 

 

The brain circuits associated with innate (as opposed to learned or socially derived) fear were elucidated by a group of Korean scientists in a 2018 study. These researchers studied the brains of mice when exposed to the odor of a predator (fox urine). They discovered that the brain circuit of innate fear runs from the front of both of the cingulate cortices to the bottom of both of the amygdalae. 

 

What allows fear to take over your life:

 

Numerous researchers have investigated fear. Some have elucidated factors that may contribute to altering the normal (even, at times life saving) phenomenon of fear and transforming it into a pathological response to non-threatening events in our daily lives.

 

Pathological fear and anxiety may be associated with an enlarged hippocampus. In a 2021 publication, scientists reported on their findings in 534 elderly people who had undergone psychological testing and brain imaging. They discovered that larger hippocampal size was associated with fearfulness and anxiety.

 

Have you ever become so scared that you froze? In a 2021 study, Japanese scientists reported on their findings in experimental rats. They found that a frightful event, which overwhelmed the ability to move, also overwhelmed both left and right sided limbic structures, such as amygdala and hippocampus. An event that does not cross the ‘freezing’ threshold, likely causes the brain to fire on the left or right side alone and  gives you just a regular scare. 

 

Fear may also spiral out of control when it involves structures outside the limbic system. In 2018, Austrian researchers suggested that our current understanding of the brain circuits that control fear is incomplete and that the cerebellum may be involved. Fear is a primal emotion, which developed long before Homo sapiens walked the earth. So it should be no surprise that evidence has accrued that one of the oldest parts of the brain may be involved in pathologic fear. The cerebellum is considered the hindbrain and is intimately associated with the brainstem. A 2015 report suggested that the brainstem itself is involved in pathologic fear responses. The scientists described links between the limbic system and the periaqueductal grey region (the midbrain area around the aqueduct of sylvius, which plays a role in behavioral responses to threatening stimuli and pain modulation). These primitive parts of the brain have been evolutionarily conserved for hundreds of millions of years and are not much different in humans than reptiles. 

 

A team of American and Canadian scientists, in their 2021 publication, reported on the effects that environmental toxins (particularly mercury, lead and polychlorinated biphenyls (PCBs))

may have on fearfulness. The researchers studied The Inuit people from Nunavik (Northern Quebec, Canada), who had lived in a pristine environment for generations. Unfortunately, some of these people were exposed to a high level of mercury, lead and polychlorinated biphenyls (PCBs). Psychological testing of the Inuit revealed that the group of Inuit who were exposed to mercury, lead and polychlorinated biphenyls (PCBs) were more fearful than those whose environment was not contaminated. Brain imaging (Functional MRI scans) of the Inuit revealed abnormalities in the cingulate cortex and the dorsolateral prefrontal cortex (attentional control, which encompasses processes such as task shifting, divided attention capability, preparation for action) of individuals exposed to environmental contamination with mercury, lead and polychlorinated biphenyls (PCBs). The scientists determined that environmental exposure to these toxins  may lead to pathological levels of fearfulness. 

 

What can you do to control your fears?

 

There are tools that you already possess that can help you take control of your fears, even when it seems like they’re in the driver’s seat. As explained in the previous section; When you’re really scared, like paralyzed with fear, deer in the headlights frightened, it may be because your reptilian brain (brain stem, controls heart rate, breathing etc) hijacks your limbic system (emotional part of your brain) shuts down your neocortex (thinking part of your brain). You may be able to conquer your fear by getting your 3 brains in sync. For more information please read https://brain2mind.substack.com/p/how-do-you-get-your-3-brains-in-sync

 

Another tool you have available to fight your fear resides in the insular cortex (part of the brain that perceives self-awareness and guides emotional aspects of social behavior). A multinational group of scientists published their analysis of available clinical studies and functional MRI data in 2018. They discovered that the insular cortex (part of the neocortex (subject to conscious control)) can extinguish the fears propagated by the limbic system. The fear control is derived from a circuit between the insular cortex and the anterior part of the cingulate cortex (part of the limbic system).

 

But if you’re looking to others for help don’t be scared!!! There are plenty of smart people working on the problem of fear control. 

 

In one recent report, the unintentional elimination of fear was described. A New Yorker (who had suffered from long-standing epilepsy) unfortunately experienced deterioration until his condition was no longer controlled by conventional methods. Things became so bad that he submitted himself to brain surgery. The doctors removed the part of the brain, which testing demonstrated the seizures to be emanating from (the right sided amygdala). After surgery, the patient noticed an unusual side effect: He no longer felt fear. Obviously, a surgery that removes a chunk of your brain is much too extreme to be used as a therapeutic option for pathologic fearfulness. On the other hand, doctors are working on different types of brain surgery that may, one day, lead to a viable treatment option. In 2018, Canadian scientists proposed that, in the future, a pacemaker-like device may be inserted into the brains of certain patients to help conquer their fear. The researchers developed a rat model of post traumatic stress disorder characterized by excessive anxiety and fearfulness. The scientists then threaded pacing electrode into the prefrontal cortex (an area of the brain responsible for decision making and attention control)  rats’ brains. They reported that the brain pacemaker mitigated fear, improved anxiety-like behavior and reversed neurocircuitry abnormalities.

 

Novel medical interventions are being developed to help fight pathologic fearfulness. In a 2020 study, researchers directed high strength magnets at the problem. The scientists used non-invasive treatment called transcranial magnetic stimulation (TMS) for patients suffering from fear and anxiety. They directed the TMS at a part of the brain called the intraparietal sulcus (a part of the brain involved with abstract thought (such as mathematics) and determining the intentions of other people). The doctors reported that magnetic stimulation of the intraparietal sulcus was effective in treating fear and anxiety. The same group of scientists, in another 2020 publication, reported their results after studying another area of the brain. The doctors were able to induce a state of fear and anxiety after using TMS to activate the right (but not left) dorsolateral prefrontal cortex (an area of the brain responsible for decision making and attention control). If you are interested in learning more about TMS, please read https://marcarginteanumd.com/can-a-magnetic-helmet-heal-the-brain-these-innovative-corporations-think-so/

 

The secret to fear control may come from a place outside your brain. The microbes in your gut may affect your level of fearfulness. A 2019 report by American scientists described how changes in the composition of an experimental animal’s microbiota also may change their fear response. The researchers discovered that the types and quantity of bugs in the gut altered the way the DNA in the animal’s brain functioned. These changes in gene activity are part of a branch of science called epigenetics and may flip the on/off switch for the genes in their brains. To learn more about epigenetics please read https://marcarginteanumd.com/its-not-just-the-cards-youre-dealt-its-also-how-you-play-your-hand/   The research suggests that, one day, doctors may be able to alter the microbiota of your gut to eradicate pathologic fear. They may do this via a process called fecal transplant (just as gross as it sounds). In other words, designer poop may make you brave. To learn more about the gut-brain axis please read https://marcarginteanumd.com/designer-poop-and-your-brain/

 

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