Introduction

As I scrolled through LinkedIn last week, I saw a post describing what I thought everyone knew was wrong. An education influencer confidently explained how teachers should target students' "emotional brain" before engaging their "rational brain," claiming this was the key to making lessons memorable. The post described the „rational brain” as purely logical, separated from emotions with the ability to override the other “brains” through willpower.

This popular idea stems from the "triune brain" theory, proposed by neuroscientist Paul MacLean in the 1960s. The theory suggests we have three distinct brains: a primitive "reptilian" brain controlling basic functions, a mammalian "emotional" brain managing feelings, and a "rational" brain handling complex thinking. While this model may seem intuitive and has influenced fields from education to management, modern neuroscience tells a different story. Far from having three separate brains, we possess one remarkably integrated organ that defies such simple categorisation.

The Myth of Three Brains

The notion that we have three distinct brains - primitive, emotional, and rational - falls apart when we look at how our brain actually operates. Modern brain imaging shows that even simple tasks engage multiple regions simultaneously. When you feel fear, for instance, there's no isolated "emotional brain" lighting up. Instead, your entire brain participates in a complex dance of neural activity.

Lisa Feldman Barrett explains in "7½ Lessons" that our brain evolved not by adding new parts on top of old ones, like geological layers, but through a process of continuous modification and integration. The regions MacLean labeled as "primitive" are actually quite sophisticated and work in concert with newer neural networks. Even the brain stem, often dismissed as purely primitive, participates in complex emotional and cognitive processes.

Consider memory formation, which the triune brain model would attribute to different "brains" depending on whether the memory is emotional or factual. In reality, creating and retrieving memories involves widespread neural networks working together seamlessly. Your brain processes emotions and rational thoughts not as separate functions, but as integrated experiences shaped by your past experiences and current needs.

This misunderstanding isn't just an academic concern - it impacts how we approach everything from education to mental health. When we understand that we have one intricately connected brain rather than three competing ones, we can develop more effective strategies for learning, emotional regulation, and decision-making.

The way our brain actually works is far more fascinating than the oversimplified three-brain model. Imagine your brain as a sophisticated prediction machine rather than a layered hierarchy. As Barrett explains, your brain's primary job is to keep your body running efficiently by constantly predicting what's coming next and what resources you'll need.

Some research, documented in works like Antonio Damasio's "Descartes' Error" and Michael Gazzaniga's "The Consciousness Instinct," shows that our brain operates through vast networks of interconnected neurons that work in parallel. Rather than having separate centres for emotion and reason, these networks collaborate to create our experiences, decisions, and behaviours.

Consider what happens when you're teaching a class or giving a presentation. Your brain isn't switching between emotional and rational modes – it's simultaneously managing multiple processes. It's predicting your students' reactions, adjusting your energy levels, monitoring the room's social dynamics, and organising your thoughts about the subject matter. All these processes involve distributed networks throughout your brain working in harmony.

Joseph LeDoux's research, detailed in "The Deep History of Ourselves," further dismantles the triune brain myth by showing how evolutionarily "ancient" brain regions participate in complex cognitive functions. Even the amygdala, often simplistically labeled as the "fear centre," plays sophisticated roles in attention, memory, and decision-making.

What makes this single-brain model so powerful is its efficiency. Rather than wasting energy managing conflicts between different "brains," your neural networks work together, sharing information and resources to help you navigate your world effectively. Understanding this integration helps explain why emotions are essential for rational decisions, and why trying to separate logic from feeling is both impossible and counterproductive.

Practical Implications

Understanding our brain as one integrated system rather than three competing parts has profound implications for how we approach everyday situations. Here are a few practical examples.

First, consider those moments when you're trying to "control your emotions." The three-brain model might suggest suppressing your "emotional brain" to let your "rational brain" take over. But this approach often backfires because it's based on a false premise. Instead, research shows that acknowledging and working with your emotions leads to better outcomes. When you feel stressed before a presentation, for instance, the solution isn't to "overcome" your emotions but to understand that your brain is preparing your body for an important task.

This insight also transforms how we approach learning and personal development. Rather than trying to engage either "rational" or "emotional" learning, effective learning strategies engage multiple aspects of experience simultaneously. This explains why methods combining physical movement, emotional engagement, and intellectual challenge often prove most effective – they work with your brain's integrated nature rather than against it.

• Rather than just memorising historical dates, students can create and perform short skits about historical events. This combines physical movement (acting), emotional engagement (character interpretation), and intellectual understanding (historical analysis).
• When learning vocabulary, students can play games where they physically act out words or concepts while incorporating them into stories. For instance, learning prepositions by creating and acting out a story about a day in the park, using body movements to demonstrate "over," "under," "through," etc.

In parenting and relationships, moving beyond the three-brain model helps us understand that phrases like "you're being too emotional" or "think rationally" are fundamentally flawed. Our decisions and reactions always involve both emotional and cognitive processes working together. Instead of trying to separate them, we can focus on understanding our reactions as whole-brain responses to our environment and experiences.

Even stress management takes on a new dimension when we understand our brain's integrated nature. Instead of seeing stress as an emotional hijacking that needs to be controlled by our rational mind, we can recognise it as our brain's way of mobilising resources to meet challenges. This perspective leads to more effective coping strategies that work with our brain's natural processes rather than fighting against them.

The key takeaway?
When we stop trying to partition our brain into competing regions and instead work with its integrated nature, we can develop more effective strategies for learning, relating, and thriving in our daily lives.

Conclusion

Our long-held belief in a three-part brain, while appealingly simple, doesn't match the remarkable reality of our neural architecture. Understanding that we have one beautifully integrated brain rather than three competing ones isn't just a matter of scientific accuracy – it transforms how we approach learning, emotional regulation, and decision-making in our daily lives.

This shift in perspective invites us to stop trying to silence our emotions in favour of reason, or to blame our "primitive brain" for our reactions. Instead, we can work with our brain's integrated nature, developing learning and coping strategies that engage our whole neural system. When we embrace this unified view, we open ourselves to more effective and natural ways of learning, growing, and navigating life's challenges.

The next time someone suggests appealing to the "emotional brain" or controlling the "primitive brain," remember: we don't have three brains in conflict – we have one remarkable organ working in harmony to help us thrive. Let's learn to work with it, not against it.