Evolutionary Context of Threats

Over the last 200,000 years, our brains have seen minimal evolution in terms of survival adaptation. However, the nature of threats we face has changed drastically. For instance, let’s contrast the primary causes of death during the hunter-gatherer era (300,000–10,000 years ago) with those in our modern, post-industrial society (1971-Present).

With advancements in technology and medicine, natural causes of death have decreased, leading to increased life expectancy. Factors such as infant mortality, infectious diseases, and injuries have also diminished due to improved healthcare. Conversely, the rise in non-communicable diseases has been alarming.

Numerous studies have shown that our bodies still react as if we were hunter-gatherers, unaware of the modern context that surrounds us. Dr. Hansen (2023) emphasizes that significant species-wide changes take millennia. Thus, our contemporary lifestyle has evolved too rapidly for our brains to adapt effectively.

Our current mindset is predominantly focused on avoiding physical threats, securing basic needs, and fostering community—an echo of the hunter-gatherer mentality.

Delving into Brain Functionality

The amygdala, situated in the temporal lobe, serves as our primary threat detector and emotional processing center. Sensory receptors relay information to the amygdala, allowing it to assess external stimuli and formulate appropriate responses. For example, if a prehistoric human encountered a charging tiger, the amygdala would trigger an alarm response, releasing stress hormones and prompting immediate escape.

The insula plays a critical role in processing the emotional and physical responses to such stimuli. It monitors heart rate, breathing, and other bodily signals to shape our feelings about experiences. When faced with a threat, like a tiger, the body reacts with intense fear.

This data is stored in the amygdala, hippocampus, and insula, so that future encounters with similar stimuli provoke caution and fear, enhancing survival chances.

A Hunter-Gatherer in a Modern World

Today's individuals are far less exposed to life-threatening dangers than their hunter-gatherer ancestors. Despite this, our brains continue to perceive threats in mundane situations—like public speaking or social interactions—which don’t jeopardize our survival. The ingrained fear response can lead to increased heart rates and heightened cortisol levels, triggering anxiety.

Anxiety is often characterized as anticipatory stress (Dr. Hansen, 2023). It stems not from actual threats, but from the perception of potential dangers. Dr. Hansen also points out that a survival-oriented mindset can predispose individuals to see danger everywhere and continually prepare for calamity.

Depression, too, is a common affliction, with over 280 million people affected globally (Dr. Hansen, 2023). Sustained stress over time is a significant trigger for depression, which may have evolved as a defense mechanism against infections.

The modern brain still reacts to perceived threats as if in the wild, leading to prolonged stress responses that can spiral into depression.

Understanding Non-Communicable Diseases

Non-communicable diseases (NCDs) are now leading causes of death, often linked to lifestyle choices like poor diet, lack of exercise, and high stress. Unlike hunter-gatherers who thrived on natural diets and active lifestyles, modern individuals often lead sedentary lives filled with processed foods and social isolation.

This historical context suggests that our mental well-being is closely tied to physical activity, nutritional choices, relationships, and having a sense of purpose.

What Can We Do About It?

Above the Iceberg

1. Exercise regularly
2. Nurture existing relationships or forge new ones
3. Make conscious dietary choices
4. Engage in fulfilling projects
5. Offer kindness to others unexpectedly

Below the Iceberg

While our bodies are wired to experience negative emotions, they are equally responsive to the benefits of movement, relationships, and healthy living. Overcoming personal challenges can help rewire our brains to view stressors as less daunting.

A simple interaction with someone you admire can shift your perspective, reinforcing the reality that many fears are exaggerated.

It's essential to remember that experiencing anxiety or stress doesn't indicate a flaw; rather, it reflects our brain's evolutionary imperative to survive. By accepting these feelings as natural responses, we can start to embrace our humanity and trust that improvement is possible.

The darkness will eventually fade, though it may not feel that way at the moment (Anders Hansen, 2023).

As a non-expert, I share these insights in hopes they resonate with you. My findings are primarily sourced from Dr. Hansen's book, The Happiness Cure. I recommend it for anyone seeking deeper understanding.

Stay tuned for more insights on leading a healthier and happier life through my newsletter, where you'll find suggestions for TED Talks and books focused on psychology and personal growth.

Take care, and see you soon!

References

Dr. Anders Hansen (2023) "The Happiness Cure: why you're not built for constant happiness and how to find a way through."

Kaplan, H., Hill, K., Lancaster, J., & Hurtado, A. M. (2000). "A theory of human life history evolution: Diet, intelligence, and longevity." Evolutionary Anthropology: Issues, News, and Reviews, 9(4), 156–185.

"Global Health Estimates: Leading causes of death." World Health Organization (WHO), 2021.

LeDoux, J. E. (1996). "The Emotional Brain: The Mysterious Underpinnings of Emotional Life." Simon & Schuster

Phelps, E. A., & LeDoux, J. E. (2005). "Contributions of the Amygdala to Emotion Processing: From Animal Models to Human Behavior." Neuron, 48(2), 175–187.

LeDoux, J. E. (2000). "Emotion Circuits in the Brain." Annual Review of Neuroscience, 23(1), 155–184.

Maren, S., & Quirk, G. J. (2004). "Neuronal signalling of fear memory." Nature Reviews Neuroscience, 5(11), 844–852.

Exploring the workings of the brain with Dr. Andrew Huberman, who discusses neuroscience and its implications for personal development.

This video delves into the nervous system's functioning and its adaptability to change, providing insights into managing stress and anxiety.