The Triune Brain in Marketing: a Beautiful Theory that Fell Apart

The triune brain theory. You may have heard about this one. Perhaps you covered the topic in your LinkedIn post. Quite possibly, you based your marketing endeavors on this idea, having read its key components in a treatise, approved by the scientific community.

Science, however, doesn’t have a tendency to stall: people evolving as a species, and, while at it, they embrace the inherent complexity of the world. As we pry further into the mysteries of the world, we realize that simplistic explanations are no longer satisfying, so we are moving on, putting forward new suggestions, conducting further research, refining the revelations of the past. In this article, we will tell why the Truine Brain Theory lost its validity, what techniques could replace the outdated approach, and what else would ensure your success.

Familliar but Wrong

The triune brain theory, proposed by a prominent neuroscientist Paul MacLean, who made significant contributions in physiology, psychiatry, and brain research, implies that the human brain evolved through three distinct stages, each corresponding to a different part of the brain. According to the good doctor’s findings,

The human forebrain evolved to its great size while retaining features of three basic formations that reflect an ancestral relationship to reptiles, early mammals, and recent mammals. The three neural assemblies… are radically different in structure and chemistry, and in an evolutionary sense, countless generations apart.

In short, a human being should thank this ancestors for the behavioral patterns they have today: reptiles and lizards reportedly bestowed on us their instinctual behaviors involved in aggression and dominance; early mammals were responsible for the motivation and emotion involved in feeding, reproductive and parental behaviors, and recent mammals awarded us with the ability for language, perception, and planning.

MacLean covertly suggested that these three brain regions were developing separately and functioned somewhat independently, which is probably the main flaw of the entire concept. But not the only one.

Busting the Triune Brain Myth

MacLean’s modern counterparts, American researchers Patrick R. Steffen, Dawson Hedges, and Rebekka Matheson formulated the three key problems connected with the triune brain theory. You can familiarize yourself with the full article on PubMed Central, it’s a fascinating read, if a little too complex for a person without any scientific background, but we will happily sum it up for you.

Patrick R. Steffen, Dawson Hedges, and Rebekka Matheson (source: fhssfaculty.byu.edu)

First of all, the authors of the article claim that the brain did not evolve in successive stages as MacLean hypothesized. Instead, all vertebrates, regardless of their species and class, share neural regions, but differ in its proportion and extent. Essentially, the human brain was not superimposed on a reptile or an early mammal brain; it simply comprises proportionally different analogous structures.

Second, these brain structures cannot function independently or in isolation from one another. When an emotional response is triggered in one area of the brain, it inevitably causes activity and interaction in multiple other regions. This interconnectedness means that no single part of the brain works alone — emotions, thoughts, memories, and social processes are all deeply linked and influence each other continuously.

Third, modern neuroscience research reveals the inaccuracy of the theory while exploring the influence of stress and change of environment. The authors provide an illustrative example in the field of fear research: human brain has no circuit that lies dormant until it is suddenly triggered. On the contrary, the brain is always active, even if you’re chilling in a hammock somewhere in Sanremo or not focused on a task.

As a result of advances in neuroscience and a deeper understanding of brain function, the triune brain theory is now widely regarded as untenable, and, therefore cannot be endorsed by the medical and scientific community due to its oversimplifications and inaccuracies. Instead, experts emphasize more complex and integrated models that better reflect how the brain truly operates.

Replaced by the Adaptive Brain

With the triune brain repudiated, what other notion can we rely on? Don’t fret, these same authors provide an apt description that better fits the situation and can be dovetailed with the general evolutionary theory: the adaptive brain. This model aligns with broader evolutionary theory and highlights the brain’s remarkable plasticity — its ability to change and reorganize itself over time. It also stresses the deep interdependence among different brain regions, showing how they work together rather than in isolation. Importantly, the adaptive brain framework recognizes the brain’s capacity to anticipate future needs and prepare adaptive responses in advance, allowing individuals to better navigate complex and changing environments.

Based on the previous conclusion that brain network always maintain activity at some level, we can conclude that the brain is continuously gauging both external and internal environments, using erstwhile experiences. Referring to the available data, our brain determines the best course of action and adjusts to the unexpected and uncertain changes. It means, essentially, that the responses our brain provides may be either strategic or tactical. Strategic responses are broad patterns, our emotional responses or sense of social connection; they can either encourage or discourage certain behaviors. For example, imagine a frustrated potential customer bumping into your ad. In this emotional state — rather negative — they’re more likely to view the ad with suspicion or annoyance, rather than curiosity. Their mood might make them overlook the offer’s value or read it as manipulative, even if it’s relevant and well-designed. If they also feel isolated or unsupported — for instance, seeing no reviews or social proof — they're even more likely to reject the message defensively, rather than engaging with it.

Tactical responses are the rapid specific actions we take in the moment to react effectively in challenging situations — like freezing, running away, or confronting a threat. In your case, when you see your campaign showing readouts you don’t really wish to see, you make a tactical decision based on your previous experience and outcomes: you either let it flow the way it is; shut it down completely, or watch further to unravel the conundrum of the readouts.

Changing the Marketing Approach

Many outdated marketing techniques refer to the triune brain theory: they try to invoke the reptilian brain or trigger fear responses to influence consumers. Sounds a little too far-fetched to be true? Recall all the time-limits you imposed on your own campaigns. While a working strategy making a user act quickly, it won’t perform with the same outstanding results if other components are overlooked. A human brain should not be underestimated and oversimplified: once the complexity of human decision-making is neglected, you are to reap a harvest of your actions.

The adaptive brain model, as we have mentioned above, dwells on a more nuanced approach to behavioral patterns. Here are the studies you can refer to while building a new campaign.

• Emotions and logic are inseparable. In the 2013 study The Cognitive-Emotional Brain: From Interactions to Integration, Luiz Pessoa explains that emotional and cognitive processes constantly interact to shape decisions.

• Context and learning are crucial. In 2017, Lisa Feldman Barrett released a book called How Emotions Are Made: The Secret Life of the Brain, where she clarified how our brains integrate past experiences to adjust responses. This seemingly useless conclusion leads to one simple thought: consumer behavior is highly context-dependent.

• Attention is flexible. Jonathan Smallwood and Jonathan W. Schooler studied the process of mind wandering, empirically proving that attention is dynamic and switches from a current task to unrelated thoughts and feelings. In terms of affiliate marketing, it corroborates the theory that marketing specialists cannot employ one single tactic to always grab attention, as user attention constantly shifts depending on context, emotions, and environment.

Together, these insights suggest marketers should move beyond simplistic appeals to primal instincts and instead focus on integrated, context-sensitive strategies that consider the full complexity of consumer cognition and emotion.

Wrapping Up

The once-popular Triune Brain Theory fell apart as it oversimplified the working process of the most complex organ in our entire body. Modern neuroscience reveals that brain functions like emotion, cognition, and social connection are deeply interconnected and adapt flexibly to context. For marketers, this means moving beyond outdated models that target isolated “brain parts” and instead embracing a more integrated understanding of consumer behavior. By leveraging this modern, science-based approach, marketers can better connect with consumers in meaningful and effective ways.