This article will help you to understand the role of the fear center, amygdala, and what you can do to calm your mind. Learn why it is important to have a strong connection between the prefrontal cortex and amygdala and what you can do to strengthen it. This area is an emerging field of science, so it is recommended to take the counsels and tips with this in mind.
Amygdala – the alarm central
The fire alarm has gone off. Everything is dark, it is in the middle of the night and you have suddenly woken up and fear your home is on fire. As you quickly sit up in bed you do not smell any smoke, but you can feel your heart is pounding away. You may also discover that your muscles are tense and that racing thoughts go through your mind.
At this moment there has gone off not just one alarm, but two. The first alarm is the fire alarm, and is constructed to set off another alarm, your amygdala.
This almond shaped structure located deep down in your brain is the alarm central of the brain and plays a central role in situations such as the one described above. Even though we do not know all of its functions it is heavily involved in processing threatening and frightening stimuli.
Amygdala normally calms down when the threat is not present anymore or when we realize that what was thought to pose a threat is not a threat after all. A typical example may be when we hear somebody running towards us from behind. For a moment we may interpret it as danger, but as we turn the head and realize that it is just a person jogging, the heart rate drops and the tension that has been built up quickly disappears.
Stress activates amygdala and “shuts down” the frontal lobe
The rational part of the brain, the frontal lobe, has just informed the amygdala that the perceived danger is no threat after all. This process happens automatically because there is usually a close and strong connection between the frontal lobe and amygdala.
In a healthy non-stressed brain the frontal lobe exerts control over amygdala and other more primitive brain structures, such as striatum – involved in regulation of habits, hypothalamus – involved in basic passions such as appetite, sexual drive and aggression, and amygdala – important for regulation of emotional reactions.
But when we are exposed to stress, particularly uncontrollable stress, fear and other frightening stimuli, important changes take place in the brain that alter the top-down regulation that the frontal lobe normally exerts over the more primitive brain centers. When amygdala detects a threat two important things happen:
- Noradrenaline and dopamine are secreted which causes the prefrontal cortex to lose its calming influence over the more primitive brain centers.
- Secondly, the activity of the primitive brain centers such as amygdala increases.
The consequence of this is that uncontrollable stress, fear and frightening stimuli make us less able to control ourselves, and we act more according to impulses from the baser and more primitive brain centers.
Symptoms of stress
We have all experienced stress in one form or another, and the effects it has on the body are broad and vary according to the intensity and duration of stress.
Physical symptoms of stress
- Headache
- Stomach and digestive problems
- Muscle aches
- Fatigue and reduced energy
- Dizziness
- Reduced sleep
Mental symptoms of stress
- Anxiety
- Panic attacks
- Depression
- PTSD
Cognitive symptoms of stress
Stress causes reduced cognitive function and particularly affects the frontal lobe and hippocampus, brain regions important for higher functions and memory.
- Reduced memory
- Inability to focus and concentrate
- Reduced learning ability
- Difficulties in making decisions
Behavioral symptoms of stress
- More easily irritated
- Anger
- Aggression
- Impulsivity
- Reduced self-control
- More unhealthy lifestyle choices including unhealthy foods, cigarettes, alcohol, etc.
Some risk factors for an overactive amygdala
Some people have a more reactive amygdala that fires more easily or intensely when exposed to stress, fear or frightening stimuli. There are certain risk factors for an overactive amygdala and weakened functional connection between amygdala and the prefrontal cortex:
Early traumatic experiences in life
Functional MRI scans have shown that orphanage children have weaker functional connection between the prefrontal cortex and amygdala. These children have higher degree of emotional dysregulation (15). Researchers believe that lack of love, empathy and other important nurturing factors that children need from their parents can explain these findings.
Chronic stress
Chronic stress appears to both expand the intricate network of connections between neurons in the deeper, more primitive brain centers and also weaken the rational part of the brain, the frontal lobe. This sets the person up to become more vulnerable when facing acute stress, such as described above. In other words, chronic stress causes us to more easily “lose control” in situations with acute stress (14). Researchers beleive that the ability to reverse the stress related changes may disappear if stress goes on for too long or is intense enough (14).
Mental disorders
Having anxiety, depression, PTSD and even chronic pain is associated with weakened functional connectivity between the prefrontal cortex and amygdala. However, as we will see later, several of the common treatments for these conditions may improve this functional connection, that is, how well the prefrontal cortex communicates with amygdala.
Lack of sleep
Sleep and emotions influence each other. Reduced sleep can lead to a weaker functional connection between the prefrontal cortex and amygdala and also increase the activity of the amygdala. This can lead to increased emotional dysregulation (2,3,4,5).
Studies have shown that when people sleep just 2-4 hours less than usual there is increased anger, irritability and reduced ability to manage frustrating situations the next day. When the researches did functional MRI scans on study participants who had reduced sleep, they observed increased reactivity of amygdala and weakened functional connection between the medial prefrontal cortex and amygdala.
In another study, researchers investigated to what extent REM sleep influence the reactivity of amygdala. REM sleep is the sleep phase where dreaming usually takes place and is a sleep phase important for maintaining good mental health. The researchers found that the more consolidated REM sleep the participants had the night before, the less reactivation was seen in the amygdala the following day during an activity that stimulated amygdala.
Strategies for strengthening the functional connection between the frontal lobe and amygdala
1. Mild stress
While acute uncontrollable stress tends to fire up amygdala and weaken its connection to the prefrontal cortex, studies have shown that young people who grow up having multiple, successful encounters handling mild stress become better at coping with stress (14). It can be likened to lifting weights. If we want to strengthen a muscle, we need regular exposure to a certain level of weight (stress). Trying to lift too heavy weights can damage the muscle, but exercising regularly with the right amount of weight will over time strengthen and grow the muscle.
Practical tips: Be involved in activities that necessitate a certain amount of effort to perform. Many people get this through regular work, but many hobbies, sport activities and activities at home (cooking, cleaning, etc.) may fall into this category.
2. Reduce stress and build resilience to stress
Stress may be beneficial to a certain level, but if the duration is too long, or the intensity is too high our health begins to deteriorate. Some people tolerate more stress than others, partly because they may be more resilient to stress. If you wonder whether you have a good stress resilience or not you may assess it by taking this test.
How can stress be reduced most effectively? Popular stress reducing techniques are just part of the solution and may not always be the most effective stress reducing strategy.
A. Address the root cause
As far as possible, try to deal with the root cause of stress. There are many types of stress, and different approaches are needed to succeed with effective stress management
- Social stress: Loneliness, challenging relationships, abuse
- Emotional stress: Fear, bitterness, frustration, sadness, anger
- Job related stress: Time pressure, scarcity of resources, efficiency requirements, downsizing, unclear management, frequent changes.
- Physical stress: Noise, physical overload, pain, lack of sleep
- Financial stress: Lack of money, mortgage, unforeseen expenses
Stress due to challenging relationships requires a different approach than financial stress. While communication and setting borders may be central to the former type of stress, budgeting, help from a financial advisor or other professional help is often the best way to go to manage financial stress.
If bitterness is the cause of stress, forgiveness, letting go of bitterness and thoughts of revenge may be your best stress managing strategies.
B. General stress reducing activities and building resilience to stress
In addition to addressing the cause of stress as much as possible, there are other things we can do to reduce symptoms of stress and build stress resilience. They include simple strategies, including selfcare:
- Regular physical activity, preferably outdoors with exposure to daylight and nature
- Be more in the present, not living with worries for tomorrow and remorse for yesterday. Children and pets seem to be the experts at being in the present
- Remember to relax, rest and get enough sleep. Take time for daily rest and vacation. Also try to include weekly rest. Jews and Seventh Day Adventists put off a whole day every week where not only do they not work, but take their mind off everyday tasks and stressors and focus on the most important and foundational aspects of life to get grounded and filled up physically, mentally and spiritually before next week begin.
- Good social connections are vital for good mental health and may increase resilience to stress
- Good nutrition
- Peace of mind, having a good conscience and an outward focus, is a stress reliever.
- Also try to include laughter, joy and a bit of humor into life. Laughter has shown to reduce stress within minutes.
3. Cognitive approaches reduces amygdala activity
Mental disorders, such as PTSD, anxiety and depression is associated with overactive amygdala and weakened functional connection with the prefrontal cortex. However, several effective treatment strategies of these conditions also “dampens” amygdala and strengthens its connection to the frontal lobe. These includes psychotherapy and cognitive behavioral therapy (22). In addition, regular physical activity, as described below, has similar effect on the brain.
Studies have shown that also cognitively demanding tasks reduces the activity in amygdala. In one study (24) researchers conducted functional MRI scans of participants with fear of snakes and found reduced amygdala reactivity when they were shown photos of snakes when participants processed the images under a high cognitive load. This correlated with participants having a reduction in perceived phobic fear when watching snake images when under a high cognitive load.
A more common situation may be worrying prior to speaking to a large crowd. Many people experience that fear and worrying are reduced when they begin to speak because the cognitive load increases as they begin the talk or presentation.
Practical tips: There are self-help books on cognitive behavioral strategies. However, if you have a medical condition described above it is recommended to get professional help from a therapist who can provide cognitive behavioral therapy or psychotherapy.
For cognitive tasks, try to divert the attention to a complex activity in which you have to use your brain actively, such as counting letters, making something, or playing a game.
4. Physical activity calms the mind
It is well known that regular physical activity may improve wellbeing and mental health. Physical activity can help reduce symptoms of stress, anxiety and depression.
In a study (10) researchers observed participants in functional MRI scans before and after physical activity. The participants either walked or ran for 12 minutes. The researchers found that
- Physical activity had a anxiolytic effect
- The anxiety reducing effect varied according to the general activity level of the participants. People who exercised more often experienced the largest anxiety reducing effect of a single bout of exercise.
- Running led to improved functional connectivity between the prefrontal cortex and other brain structures, including amygdala
Practical tips: Exercising outdoors can increase the positive effect physical activity has on amygdala, particularly if you exercise in nature, on a sunny day or in daylight. Read on for more information.
5. Nature dampens amygdala
Closely associated with physical activity are nature experiences. We have probably all experienced the positive effect nature has on body and mind. Spending time in nature can reduce stress, improve mood and cognitive function and has also shown to positively affect amygdala.
In an interesting German study the participants either walked for one hour in a forest, or one hour in a busy street in Berlin (9). Prior to the walk and right after the walk the participants underwent a functional MRI scan. The results showed that participants who walked one hour in the forest had reduced activation of amygdala when faced with stress, while participants who had walked the busy street in the city did not experience the same effect.
Practical tips: Try to combine nature experience with physical activity
6. Light affects amygdala
Several studies suggest that exposure to daylight, or blue light strengthens the functional connection between the prefrontal cortex and amygdala. In a study conducted at the university of Copenhagen (21) 30 healthy individuals received 30 minutes of light exposure every morning for three weeks. At the end of the three weeks the researchers observed the following:
- The brains of the participants who received light therapy/exposure reacted less to faces showing fear or anger
- The brain was more able to control the fear center, amygdala
- This effect on the brain was related to light intensity. The more intense light the participants were exposed to, the greater was the calming effect on amygdala
The researchers concluded that light strengthens the communication between the frontal lobe and amygdala. The prefrontal cortex seems to down-regulate the activity of amygdala, the part of the brain that plays a central role in our emotional response to our surroundings (7)
Findings from other studies suggest that the calming effect light has on amygdala may appear soon after light exposure (8)
Practical tips: Try to combine physical activity, exposure to nature and daylight or sunlight
7. Sleep your way to a calmer brain
As mentioned earlier in this post, sleep and emotions influence each other. Lack of sleep may lead to a weaker functional connection between the frontal lobe and the amygdala. Studies have shown that just 2-4 hours less sleep increase frustration, irritability and makes it more difficult to handle challenging situations the following day. So how do get the sleep that the body needs? If you struggle with sleep try these practical tips:
- Plan your day around optimizing sleep. Wake up and go to bed at the same time every day. One hour +/- is acceptable. Calm down the last hour before retiring to bed.
- Arrange your sleeping environment to facilitate sleep. Keep the sleeping room dark, not too warm, and with as little noise as possible
- Exposure to daylight early in the day, preferably combined with physical activity improves sleep
- Regular physical activity improves sleep, but for some it can worsen sleep if done late in the evening, or in the beginning of an exercise program.
- Avoid stimulants that may keep you from falling to sleep and remain in sleep. Stimulants include nicotine and caffeine. Alcohol may help some people fall asleep but reduces sleep quality and sleep structure and is not recommended for optimizing sleep.
- Avoid blue light (screens) during the last hours before going to bed as it reduces melatonin secretion
Sleep issues are very often caused by underlying mental health issues, such as anxiety, depression and stress. Deal with these underlying issues if they are present and sleep will usually improve as mental health improves.
For assessing how severe your sleep problems are you may take the Insomnia Severity Index test
If your sleep problems have lasted for several months, cognitive behavioral therapy for insomnia is one of the most recommended and effective non-drug strategies to improve sleep.
See the video below for more information about how to treat insomnia
8. Good social connections strengthens desirable brain connections
As mentioned earlier in this post, studies have shown that lack of a good parental relationship in childhood, or traumatic experiences in early life may reduce the functional connection between the prefrontal cortex and amygdala thus increasing the risk for emotional dysregulation.
There is some evidence that increased positive social interaction and support may reduce activity in the limbic system including amygdala and that this may be mediated through greater activity in the prefrontal cortex (25)
Practical tips: Maintain good social relationships or connections and seek social support if you are facing challenges that increases your stress level.
9. Faith in a loving God calms amygdala
For people of faith studies have shown that when people experience and worship a God of love, who loves freedom, it strengthens the frontal lobe and calms the limbic system including amygdala (5).
Practical tips: For more information about this topic view the video below by a christian psychiatrist
10. Nutritional factors that may affect amygdala and its connection with the prefrontal cortex
A. Alcohol. Studies have shown that people who have developed dependency to alcohol can have reduced functional connectivity between the prefrontal cortex and amygdala, even several years after they have stopped drinking (11).
B. Caffeine. Caffeine stimulates secretion of stress hormones and may in some people cause symptoms of anxiety. Studies suggest that one of the possible mechanisms may be increased activation of the fear center, amygdala (17). Caffeine appears to be unhelpful in this area, particularly if we are already stressed. Stress has a tendency to make us focus om negative things, and caffeine has shown to amplify this phenomenon and can increase negative emotions during stress (18)
This effect is possibly stronger among people who do not drink coffee on a regular basis. There are mixed findings in studies on caffeine and stress activation.
C. Tryptophan. This essential amino acid is the building block of the neurotransmitter serotonin. Serotonin is involved in regulation of mood, sleep, pain, appetite, and is also an important nerve signal in the nerve circuits that connects the prefrontal cortex with amygdala. Functional MRI examinations have shown that when tryptophan is excluded from the diet it affects the functional connectivity between the frontal lobe and the amygdala (13)
Practical tips: Try a month or two without caffeine and see if it makes a difference when you are facing stress. Tryptophan depleted diets does not exists outside the “laboratory”, so this is not a recommendation to supplement with tryptophan.
11. Deep breathing and relaxation
Functional MRI scans have shown (1) that being conscious about ones breathing is an effective tool for regulation of negative and aversive emotions. Researchers observed that being attentive towards our breathing downregulated amygdala reactivation and strengthened the amygdala-prefrontal integration. In addition it increases the parasympathetic nervous system which inhibits amygdala activation.
Simple relaxations exercises may also contribute in reducing the stress response and an overactive amygdala (23).
Practical tips: When stressed up and confronted with frightening and fearful stimuli try to focus on deep breathing. Add a few periods of relaxation exercises on very busy and stressful days.
Conclusion
Even though the science is not yet settled on this emerging and complex topic there is some evidence to suggest that how we treat our body and mind may influence our brains. Regular physical activity, enough sleep, social support and meaningful social connections, avoidance of risky substances and stimulants, effective stress management, frequent exposure to nature and daylight, and other factors, may help to calm the mind more easily during stressful situations.
References
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- Krizan, Zlatan, and Garrett Hisler. “Sleepy anger: Restricted sleep amplifies angry feelings.” Journal of experimental psychology: general 148.7 (2019): 1239.
- https://studyfinds.org/study-losing-sleep-worsens-anger/
- Yoo, Seung-Schik, et al. “The human emotional brain without sleep—a prefrontal amygdala disconnect.” Current biology 17.20 (2007): R877-R878.
- Wassing, Rick, et al. “Restless REM sleep impedes overnight amygdala adaptation.” Current Biology 29.14 (2019): 2351-2358.
- https://www.psychologytoday.com/us/blog/the-athletes-way/201512/sleep-loss-disrupts-emotional-balance-the-amygdala
- https://videnskab.dk/krop-sundhed/morgenlys-mindsker-angst/
- McGlashan, Elise M., et al. “Afraid of the dark: Light acutely suppresses activity in the human amygdala.” PLoS One 16.6 (2021): e0252350.
- https://www.psypost.org/2022/09/experiment-reveals-that-a-one-hour-walk-in-nature-reduces-amygdala-activity-which-may-protect-mental-health-63972
- Chen, Yu-Chun, et al. “Habitual physical activity mediates the acute exercise-induced modulation of anxiety-related amygdala functional connectivity.” Scientific reports 9.1 (2019): 1-12.
- Wade, Natasha E., et al. “Blunted amygdala functional connectivity during a stress task in alcohol dependent individuals: A pilot study.” Neurobiology of Stress 7 (2017): 74-79.
- https://inside.uncc.edu/news-features/2019-04-11/caffeine-can-darken-moods-people-face-work-stress-say-researchers
- Passamonti, Luca, et al. “Effects of acute tryptophan depletion on prefrontal-amygdala connectivity while viewing facial signals of aggression.” Biological psychiatry 71.1 (2012): 36-43.
- Arnsten, Amy, Carolyn M. Mazure, and Rajita Sinha. “Neural circuits responsible for conscious self-control are highly vulnerable to even mild stress. When they shut down, primal impulses go unchecked and mental paralysis sets in.” Scientific American 306.4 (2012): 48.
- Fan, Yan, et al. “Early life stress modulates amygdala‐prefrontal functional connectivity: Implications for oxytocin effects.” Human brain mapping 35.10 (2014): 5328-5339.
- Shou, Haochang, et al. “Cognitive behavioral therapy increases amygdala connectivity with the cognitive control network in both MDD and PTSD.” NeuroImage: Clinical 14 (2017): 464-470.
- Smith, Jessica E., et al. “Storm in a coffee cup: caffeine modifies brain activation to social signals of threat.” Social cognitive and affective neuroscience 7.7 (2012): 831-840.
- https://inside.uncc.edu/news-features/2019-04-11/caffeine-can-darken-moods-people-face-work-stress-say-researchers
- Newberg, A. (2009). How God Changes Your Brain. New York: Random House, p. 53.
- Sripada, Chandra Sekhar, et al. “Oxytocin enhances resting-state connectivity between amygdala and medial frontal cortex.” International Journal of Neuropsychopharmacology 16.2 (2013): 255-260.
- https://sciencenordic.com/denmark-sleep-disturbance-stress/morning-light-relieves-anxiety/1397274
- Oh, Dong Hoon. “Traumatic Experiences Disrupt Amygdala–Prefrontal Connectivity.” The Amygdala-A Discrete Multitasking Manager. IntechOpen, 2012.
- https://www.health.harvard.edu/staying-healthy/understanding-the-stress-response
- Loos, Eva, et al. “Reducing amygdala activity and phobic fear through cognitive top–down regulation.” Journal of Cognitive Neuroscience 32.6 (2020): 1117-1129.
- Eisenberger, Naomi I., et al. “Neural pathways link social support to attenuated neuroendocrine stress responses.” Neuroimage 35.4 (2007): 1601-1612.