Neuroimmunology: Surprising Facts How Your Psychic Affects Your Health

Have you ever faced a very unpleasant situation, then strangely woke up sick the next day?

Have you ever had a very stressful period of your life yet, suffered a significant decline in your immunity afterward?

Do you often blame your physique for being so fragile?

Don’t; you are not the only one whose physical health is bound to your nervous system and emotional well-being.

But what does the nervous system or emotions have to do with decreased immunity, weakness or even sickness?

Isn’t the nervous system a bunch of signals going back and forth between our body and our brain in response to the surrounding events?

The truth is, there is more to our nervous system than meets the eyes.

Neuroimmunology And Amazing Facts About Our Nervous Systems


There is a magnificent fact about our bodies that Scientists never cease to admire; its intelligence.

Our bodies are a very sophisticated creation with unlimited capacities.

The complexity of the processes inside our bodies makes it very hard to capture.

Every breakthrough in the field of neuroscience confirms the fact that we are in front of one of the smartest, if not “the smartest,” systems ever.

Our nervous system is an essential element of this masterpiece.

It is not just some neurons carrying electrical signals to and from the brain.

Our nervous system is a very advanced system of communication whose intelligence, speed and coordination are unmatched.

With 100 billion neurons in our brains and 13.5 million in our spinal-cord, our neurons outnumber the stars in our galaxy.

Our neurons travel with 100 m/sec speed and form about a 965 km distance if lined up.

All these abilities are performed with a structure that weighs mostly 1375 grams!

This high degree of sophistication and interdependence requires an equal level of understanding and appreciation.

Just like every masterpiece, its operation manual is the key to handling and maintaining it with a standard.

Anatomy of Our Nervous System

The word nervous system refers to our brain as well as the nerves in our bodies.

Our nervous system is the leader of our bodies; it regulates and coordinates what happens inside it.

It has four main functionalities, sensory, communicative, integrative and motor functions.

The sensory function is responsible for gathering information from our different senses.

Communication then happens by sending the received information to the brain and spinal cord.

This information is then processed during the integration process.

And eventually, a response is generated based on the processed information.

This ingenious system consists of two main systems:

1- Central Nervous System

It includes the brain and the spinal cord.

2- Peripheral Nervous System

It consists of the motor neurons and sensory neurons.

The Peripheral Nervous System carries different messages from our body organs and to the brain.

It is responsible for the smooth functioning of our heart, respiratory system, digestive system, urinary system, reproductive system, and blood vessels.

It is the reason why we can sleep at night without worrying about heartbeats or respiration.

However, a critical subsystem of the peripheral nervous system holds the key that unlocks many of our physical mysteries.

It is our autonomic nervous system (ANS).

Autonomic Nervous System

autonomic nervous system

The autonomic nervous system controls our involuntary actions and consists of two subdivisions, the sympathetic division, and the parasympathetic division.

The sympathetic division is one of interest to us.

This division is the one responsible for our fight or flight response, also known as the acute stress response.

Do you remember the time when you had to give that speech in public?

Do you still recall how your heart was beating fast, and your hands were sweating?

Your body’s reaction to that stressful situation was the fight or flight response of the autonomic nervous system.

In other words, it is the sequence of reactions that our body generates to deal with threating situations.

But how does our nervous system identify a situation as stressful in the first place?

What is Stress and How Do Our Bodies Respond to it?

Dr. Hans Selye, a Hungarian endocrinologist, defined stress as the sum of all non-specific systemic phenomena elicited by sudden exposure to stimuli to which we are quantitatively or qualitatively not adapted.

When this happens, and the situation is defined as stressful, our hypothalamus is activated.

The hypothalamus is the part of our brains responsible for dealing with stress.

When faced with stress, it initiates the fight or flight mode.

The fight or flight, which is also known as the alarm stage, is the body’s general adaptation to external stimuli.

Our hypothalamus activates the pituitary gland, which activates the adrenal glands.

The adrenal gland releases cortisol as a mechanism of adaptation to stress.

Cortisol increases glucose in our bloodstream, helping our brain to make good use of glucose to repair any damaged tissues.

The hypothalamus also activates part of the autonomic nervous system, which in turn secretes adrenaline hormone.

The release of adrenaline triggers somebody reactions including increased heartbeats, shallow breathing, and muscle tension, as well as sweating, anxiety and sometimes nausea.

Of course, the magnitude of these reactions varies from one person to another.

However, stress doesn’t not only affect our involuntary responses, but it also affects our immunity, hence our physical well-being.

Neuroimmunology And Our Immune System


Our immunity is our silent worrier; it protects our bodies from foreign invaders and potential threats.

It consists of protein, cells, and tissues.

Our immune system has four main lines of defenses that it uses against external threats:

1- Anti-body mediated immunity

This line of defense is responsible for the release of antibodies into our bloodstream.

2- Cell-mediated immunity

This cell-mediated immunity secretes several cytokines that influence the function of other cells.

It protects us against microbes, viruses and other threats like cancer.

3- Phagocytic system

This line of defense is present in our lymph nodes and spleen.

It is responsible for the formation of red and white blood cells, plasma proteins as well as storage of iron.

4- The complement system

This line of defense enhances the ability of the released antibodies to fight infections, as well as other attacks.

In response to external threats, our immune system releases biochemical that works against these threats.

Unfortunately, some of these chemicals are toxic and can cause damages to our bodies if it stays in our bloodstream for long.

Inflammation is another trick played by our immunity to protect our bodies from injuries.

Neuroimmunology And Stress

In the 1980s the psychology doctor Janice Kiecolt-Glaser and the immunology doctor Ronald Glaser were intrigued by the link between stress and infection.

In their conducted studies, they found out that during a stressful exam period, students’ immunity decreased and almost stopped producing infection-fighting cells.

This observation intrigued other researchers and scientists to investigate the matter further.

The fruits of these researchers were eye-opening.

Our bodies are the remedy and the disease in cases of stress, especially chronic stress.

The “fight or flight” mood activated by our brains are crucial to our survivor, yet, when our body fails to release it, it turns against us.

“Fight or Flight” mood is intended towards external threats but is never meant to become a way of living.

Both our nervous system and immune system are impacted during this mood.

Our immunity is designed to prepare our body against external threats, and so does our nervous system.

When our nervous system releases cortisol, it suppresses other body functions, including the digestive, reproductive and most importantly immune system.

Although it might be essential to our body’s adaptation, yet, cortisol represents a significant threat to our health.

When stress persists, our bodies fail to release the “fight or flight mood” to get back to a normal state.

Consequently, cortisol builds up in our blood and hijacks our body in many ways.

Increased level of cortisol can lead to weight gain, chronic headaches, anxiety, digestive problems, recurrent colds, heart disease, as well as concentration and insomnia.

Because cortisol inhibits the functionality of our digestive system during stress, it could cause stomach ulcers.

Cortisol also weakens our immunity by decreasing the number of white blood cells.

A weakened immune system can lead to many immune system diseases, including Inflammatory bowel disease, Arthritis, Fibromyalgia, and Psoriasis.

On the other hand, the release of adrenaline in reaction to stress releases fatty acids which could lead to increased cholesterol level.

This increased cholesterol level could lead to high blood pressure and blood clots formation, which in turn could lead to strokes.

Too much stress can also put you in risk of type 2 diabetes.

Yet, the most dangerous impact of stress is in getting used to it, not realizing how much it is jeopardizing your health and killing you slowly.

Symptoms of Stress

Many signs of stress could pass unnoticed because it is similar to other symptoms.

However, some popular symptoms are:

1- Feeling Unhappy or distressed

2- Worrying too much

3- Suppressed anger that you are not aware of its reason

4- General Fatigue

5- Eating too much or too little

6- Thinking constantly of the worst-case scenarios

7- Being impatient most of the time

8- Overthinking

9- Looking for distractions all the time, whether it is by keeping yourself busy, or through consuming addictive material

10- Feeling demotivated most of the time

11- Teeth Grinding, especially while sleeping

As for the unpopular signs

1- Muscle tension, especially at your neck and in between your shoulders

2- Frequent infections

3- Constipation

4- Acne

5- Heart palpitations

But What Causes Stress?


Many reasons cause stress, yet, it differs from one person to the other.

However, since we are partners in the same humane journey, we share many of these reasons:

1- Facing fearful situations

Fear can come in different shapes and colors.

We fear death, heights, loss, uncertainties, confrontations, judgments, physical pain, loneliness, rejection, as well as many other things.

Yet, fear is one thing and living with a persisting fear is entirely something else.

Constantly facing what we fear is enough to stress you out for the rest of our lives.

As we are not designed to live in a constant state of fear.

2- Our views of the world

Perception is projection! And What you see is what you get.

Our perception and beliefs about the world play a significant role in the quality of our life.

If our glasses are black, then the world does have a lot that stresses us out.

However, if you change the way we look at things, the things we look at change!

3- New situations

Changing jobs, moving to a new place, starting or ending a relationship can all be stressful.

4- Getting out of our comfort zone

Challenging ourselves outside of our norms can be very stressful, yet it is a prerequisite of life.

Growth is on the other hand of our comfort zones.

5- Financial Insecurity

Not having enough money to cover you up and not knowing how you will manage can eat you alive.

6- Being stuck in an unpleasant situation

Whether it is as simple as a college, you don’t like or as big as living in settlements, being out of your basic norm is no doubt stressful.

7- Peer pressure

If nothing is on the list but peer pressure, it would be enough to do the job.

Our life nowadays is governed to a great extent by societal norms in which peer pressure plays a significant role.

Whether it is choosing our careers, partners, schools, or country to live in, peer pressure decides for us.

We are all stuck at one or more of these situations, yet, challenges are mandatory to our growth.

It is how we react to these challenges that makes all the difference.

Yes, we are living in the most stressful of eras, still, how much it gets to us remains our choice.

A Final Word

Our bodies are a magnificent and very smart creation that is sophisticatedly integrated.

Our physical well-being goes hand in hand with our psychological well-being.

Emotional stress impacts our immunity system heavily, and hence causes its degradation.

That is why it is not random that we feel sick after a very stressful period because our immunity decreases.

Neuroimmunology is the field that helps us understand how our nervous system and immune system are intertwined.

So, next time you don’t feel well after a tiring debate, you can easily solve the mystery

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