The Evolutionary Mismatch Basis of Emotional Disorders

Have you ever wondered why so many of us suffer from mental disorders? According to the Anxiety and Depression Association of America, anxiety disorders are the most common in the U.S. affecting 40 million adults aged 18 and older. The numbers for depression are also alarming with approximately 3.3 million Americans adults suffering from the disorder. Currently, depression is the leading cause of disability for those between the ages of 15 to 44.3 years in the U.S. For a more complete list of anxiety and depression facts, read here... 


Society, Evolution, and Mental Disorders

When we consider mental disorders such as anxiety and depression, we think of these disorders as something that occurs in the individual. If the individual is having a problem, the cause and the solution should also lie within the individual; however, evolutionary researchers are suggesting that modern society is paying a significant role in the development of mental disorders.

From an evolutionary point of view, illnesses such as ADHD, Autism, and Alzheimer's should not be anywhere near as common as they are. However, it may be that the environment we live in is not compatible with the environment we evolved in. Consider the stress-diathesis model of mental illness, this model postulates that a predisposition to an illness can exist, but it will not manifest if the individual lives in a healthy environment. If the individual is exposed to stressful circumstances, the illness is much more likely to develop.

Today, we know there are many detrimental effects of chronic stress on our mental, emotional, and physical health. We can also see how the evolution of modern society is causing heightened levels of stress in the population. It is the mismatch between the evolution of society and the physiology of our brains and nervous system that is hypothesized to play a role in the development of such high levels of mental disorders such as depression and anxiety.


Chronic stress, evolution, and mental illness

We've all heard of the fight or flight response, the way in which our body responds when we perceive ourselves to be in danger. The sympathetic nervous system becomes activated, setting off a  range of physiological changes such as the rapid release of catecholamines from the adrenal glands that prepare the body for quick, life-saving action Our heart and respiration rate increases, our eyes dilate, and the body is ready to fight or run. This state demands a substantial amount of energy that in its original intention is worth the expenditure as it gives us the best chance to save our own life.

Evolution has designed us in such a way that the sympathetic nervous system becomes activated whenever we perceive danger whether we want it to or not. The system is quick and extremely effective if we encounter a bear in the woods or a hostile man in a dark alley somewhere. Unfortunately, in modern society, our heightened response to stress can become chronically activated. Running late for meetings, worrying about worst-case scenarios such as losing our house, our jobs, or an important relationship, all activate a similar sort of survival fear. The body is not meant to deal with survival stress in an ongoing way. It is, for this reason, it seems the nature of society is causing a situation that we have not evolved to deal with.  For further reading on the evolutionary mismatch of mental illness read here ...

The stress response evolved in conditions where the fight or flight response is followed by rest and recovery. Under these conditions, the system serves us well, however, the physiological changes that occur when our fight or flight response is activated can cause significant damage when it becomes chronic.


The connection to today's diseases

The chronic stress we see today is associated with physical ailments such as autoimmune diseases, allergies, and a variety of other conditions caused by inflammation. We know after decades of research that the impact of chronic psychological stress on the body is substantially and is detrimental to our mental and emotional health.


What we can do

I would argue that today, one of the most important things we can do for ourselves is to learn how to listen to our body. Next, we need to be willing to make the changes necessary to keep us healthy — not just physically, but also mentally and emotionally healthy. Reducing activities in our schedules that are not necessary and saying no to what is not truly important to us is one fundamental way to free up some of our limited time and energy. This may involve living a simpler, less expensive life and practicing "essentialism" in determining where we put out time and resources.

In addition to implementing lifestyle changes that protect us from cluttering our schedules and exposing ourselves to situations that can cause chronic stress, below are a few tips to help relieve and reduce stress.

  • reduce exposure to the news
  • implement a regular exercise routine
  • learn and practice mindfulness
  • find a therapist who practices cognitive behavior therapy (CBT) to help you learn effective coping skills as well as to identify and reconstruct negative thought patterns


Take a preventative approach

Awareness of the causes and effects of chronic stress can motivate us to take preventative measures to reduce stress and increase wellbeing. If we implement lifestyle changes we can avoid the need for and use of medications such as antidepressants and their side effects. Techniques such as those listed above are helpful in relieving the body and mind of chronic stress.

Dr. Redman is a Clinical Psychologist practicing in Sarasota Florida. If you would like to learn more you can visit his website here.

Anxiety Current Issues Stress Work-life balance
Understanding symptom overlap between anxiety and ADHD

Anxiety and ADHD are separate conditions but for a lot of people, they occur together. It is important to understand sym...

By Psychology Everywhere Staff
February 06, 2020
What does adult ADHD look like?

Are you struggling with ADHD symptoms? About one-third of children diagnosed with ADHD continue to experience symptoms i...

By Psychology Everywhere Staff
January 29, 2020