Letter 7: The Neurons that Fire Together Wire Together

“Between stimulus and response there is a space. In that space is our power to choose our response. In our response lies our growth and freedom.”

—Viktor Frankl

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Dear Future Human,

In previous letters, I have done my best to prepare you for the complex web of threads that I am planning to share with you, with the hope that I will be able to weave them into a coherent tapestry. As I write this, I can’t help but laugh to myself, appreciating how lofty this intention is—to integrate the threads of evolutionary biology, neuroscience, psychology, sociology, anthropology, philosophy, religion and spirituality—all the dynamic forces of Nature that shape our current human predicament into a single holistic picture. I admit, I am hardly an expert in most of these fields. Still, after years of study and their application in my clinical work, with significant reliance on my intuition, I’ve come to understand many of them—some more deeply than others. In the process I have learned how together they shape our thoughts, feelings and behaviors.

In this letter, I will explore the role that neurobiology plays in shaping our automatic thinking, how it limits our perception, influences many of our decisions, and keeps us stuck in old patterns of thought and reactivity. This exploration is not meant as a technical or authoritative explanation; but rather to give you only the key ideas and perspectives that hopefully will help illuminate the broader points I wish to make.

Recent breakthroughs in neuroscience have been the catalyst for helping me see more clearly why we need to intentionally evolve our perceptual capacities by widening our lens of perception through rewiring our brain. Although still in its infancy, the knowledge we have gained so far offers a promising path toward the intentional rewiring of our brain.

The primary questions we must examine are why we are not actively responding to the threats that are clearly coming our way.¹ Why are we not mobilizing to protect ourselves?

The answer lies in how the human brain has evolved to perceive danger and why that wiring no longer serves the world we live in.

The biggest issue is at the center of the emotional brain, the amygdala. This ancient part evolved to detect immediate visible dangers and trigger quick instinctive responses.² It is not equipped to deal with complex, abstract or distant dangers. As a result, long-term or abstract dangers, like climate change, economic or social collapse, often fail to activate any sense of urgency and the need for action.³

Compounding this issue is the fact that the brain is wired to conserve energy. In order to be efficient and minimize the use of valuable resources, it establishes shortcuts—habits, assumptions and automatic responses.⁴ These adaptations, once useful for our survival in simpler environments, narrow our perceptual awareness in today’s complex world. Consequently, they limit our ability to perceive, feel or fully comprehend the broader consequences of our actions.⁵

Our disconnection from the natural, interdependent world further exacerbates this pattern. When we act as if we are separate, we fail to see that the human condition is governed by the same natural laws as other organisms. If we did, we would spend less time blaming and more time trying to understand each other. We would inquire into our destructive behaviors with the same curiosity we bring to the natural ecosystem.

The fact is that our brain itself is a kind of ecosystem. From the moment we are born, the brain begins to build neural networks. The various brain regions communicate through electrical and chemical signals that are determined and shaped by our experiences. These neural connections form the very foundation of our perception, thoughts, behaviors, and beliefs. In the neuroscience field this is known as “what fires together, wires together,” which explains this process: when neurons are consistently activated at the same time, their connection grows stronger.⁶

In infants, this process unfolds very quickly. A newborn has over 100 billion neurons, but they are not connected yet. When human infants are born, their brains are unfinished, waiting for wiring instructions from their environment. It’s through everyday experiences—being cuddled, fed, talked to, or just crawling—that these connections start to form. In the first few years of life, the brain can create up to a million new connections every second. This remarkable system evolved to help young children rapidly learn language, interpret their world, and develop social and emotional skills.⁷

However, in order to conserve energy and resources, it doesn’t keep all connections. At around age two, connections that are seldom used begin to be eliminated. This “use it or lose it” strategy not only conserves energy but also optimizes the brain for the specific environment in which a child is raised.⁸

Simultaneously, a myelination process is underway. This process coats the neural pathways with a fatty substance called myelin, which makes the most frequently used circuits faster and more efficient.⁹ By the time a child starts kindergarten, approximately 90% of this foundational brain structure has already been laid down.¹⁰

This early brain architecture is what later drives much of our automatic, unconscious thinking. As Daniel Kahneman described, most of our thinking runs on fast, automatic processes—System 1—built early and strengthened through repetition. That explains why neuroscientists estimate that up to 95% of adult thinking happens unconsciously.¹¹ Slower and deliberate thinking—what Kahneman called System 2—is possible, but it requires effort to interrupt this very fast system.¹² In future letters, I will explore how this interruption becomes possible.

One of my favorite ways to illustrate how repeated practice turns a new skill into something automatic is by examining the act of learning to drive. Reflect on how mindlessly you sometimes drive a car (so much so that often you find yourself pulling up to your home without remembering the drive from work).

I remember learning to drive. At first, I needed to exert intense focus—on pedals, mirrors, road lines, speed, and signals—all at once. Over time and through repetition, these separate tasks became unified, mostly automatic activity.¹³ Eventually I was able to drive while sipping coffee, chatting with a friend, or ruminating over an unpleasant interaction in the grocery store.

This same process that shapes our skills also shapes our emotional and relational patterns. Warm, responsive caregiving generally provides the child with a more secure attachment development and healthier emotional regulation.¹⁴ Stressful or neglectful environments can lead to overactive stress systems, like a hypersensitive amygdala (the brain’s alarm system). These early experiences influence how adults experience fear, trust, intimacy and connection.¹⁵

I invite you to pause for a moment and let this in: many of your automatic thoughts, feelings, and behaviors were embedded in early childhood—when you were most vulnerable, emotionally and cognitively undeveloped, and entirely dependent on the adults around you. These early experiences became the lens through which you now perceive threat or safety, rejection or acceptance.

Think about the implications for your everyday life, and for your relationship with others. Much of how you feel, think and behave as an adult is still guided by the perception of your younger self who needed to feel belonging and safety. This explains why so many people fear rejection, why feelings of helplessness can arise so quickly and why people seek direction and reassurance outside themselves. Together, these early patterns give each of us a unique psychological, perceptual, and cognitive lens through which we see and move through the world.

But the good news is, thanks to neuroplasticity, healing and growth remain possible throughout life. In every moment, neurons are firing, forming new connections, and adapting in response to engagement with our environments and people around us. With awareness, intention and sustained practice, even deeply ingrained patterns can rewire. We are not fixed in time. We are continually learning, unlearning, and reshaping ourselves in response to the world around us. Each new choice, each moment of awareness, creates an opportunity to rewire our minds and reclaim our potential.¹⁶

The question before us—do we choose to continue operating from outdated neural circuitries—patterns created in childhood and reinforced into adulthood—or do we choose to consciously and intentionally rewire ourselves to meet the world as it is now?

I don’t know. In case we didn’t…

In following letters, I will explore what it would take to shift our perspective.

Hopeful,

Ronit

1. United Nations Sustainable Development Group, 2024 SDG Report: Global Progress Alarmingly Insufficient, June 2024.

2. Daniel Goleman, Explanation of “Amygdala Hijacks”, Emotional Intelligence Clips, December 2020.

3. Ailsa Chang and Daniel Gilbert, Why Climate Change Threats Don’t Trigger an Immediate Response From Human Brains, NPR, December 2019.

4. Nikhil Swaminathan, Why Does the Brain Need So Much Power?, Scientific American, April 2008.

5. Kinnu, How do Mental Shortcuts Influence our Decision-Making?, Kinnuverse, June 2025.

6. Michael Netzley, What Fires Together, Wires Together, Medium, November 2022.

7. Center on the Developing Child at Harvard University, Brain Architecture, retrieved May 2025.

8. Elisabeth Evans, Denali Schmidt, and Alexandra Urban, Synaptic Pruning, Brown University, December 2014.

9. NeuroLaunch Editorial Team, Myelination in the Human Brain: From Development to Adulthood, NeuroLaunch, September 2024.

10. Bipartisan Policy Center, The Science of Early Childhood Development, retrieved May 2025.

11. David Eagleman, Powers of the Subconscious, Closer to Truth, retrieved May 2025.

12. Joshua Loo, System 1 and System 2 Thinking, The Decision Lab, January 2026.

13. Rhitu Chatterjee, Again! Again! Here’s Why Toddlers Love to Do Things on Repeat, NPR, January 2024.

14. Jack P. Shonkoff, Brain Builders: Why Healthy Development in Children is So Important, First Five Years Fund, February 2020.

15. Greer Kirshenbaum, The Power of Being Connected to Your Baby, Psychology Today, October 2024.

16. Andrew Huberman, What is Neuroplasticity?, The Science and Cocktails Foundation, April 2023.

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