Primul episod al podcastului Mind Architect este despre creier și despre arhitectura acestuia. Ascultându-l, o să afli de ce acest model de reprezentare a creierului ne ajută să înțelegem de ce facem lucrurile pe care le facem, așa cum le facem. Bonus, vei primi și câteva sfaturi practice despre cum să folosești informația de la Paul în viața de zi cu zi.

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How we work with three brains

The metaphor of the three brains appeared when American physician and neuroscientist Paul D. MacLean came up with the concept of Triune Brain in the 60s, and brought it in the spotlight in his 90s book The Triune Brain in Evolution.

Still covered in many textbooks and course lectures in biological psychology, his theory states that we have threecortical structures that belong to very different evolutionary eras. This model was associated with Freud’s tripartiteview of the mind, with its conflicting superego, ego and id. The theory’s conceptual beauty and intuitive appeal lent it enormous staying power.

Let’s dive deeper into these three components:

Reptilian brain (old brain / lizard brain)

This is the oldest cortical structure: it appeared in fish nearly 500 million years ago, continued to develop in amphibians, and reached its most advanced stage in reptiles roughly 250 million years ago.
Its main role is to control the body’s vital functions: heart rate, breathing, body temperature, balance, etc., basically to keep us alive and
It routes the information up and down in our organism: takes it from the other structures and forwards it to the body as commands, and also receives sensory information from the body (via the spine) and sends it to more advanced structures for more in-depth
It’s something reptiles, mammals and us — humans —

Limbic brain (paleomammalian brain)

This structure is roughly 150 million years old, so a bit younger than the latter.
Among its core functions are memory formation, stress response, and plays a key role in a large variety of emotions like fear, anxiety, anger etc., and also allows us to develop attachment bonds with each other.
It impacts the way we interact with other creatures, as it biologically enables us to create connections, something we also see in mammals.
Only mammals and humans share this structure.

As an example, when reptiles give birth, they sometimes abandon their eggs and do not care for their children (or even worse, they might even see them as dinner). In contrast, one of the strongest and most studied attachment relationships formed in mammals is the mother-infant bond.

Neocortex (neomammalian brain)

The most recent step in the evolution of the brain, being about 150–200.000 years old
Found uniquely in higher mammals — especially
Provides us with our superior functions, such as speaking, abstract thinking, planning, perception and the ability to inhibit our emotional impulses.

As an example, when a superior/parent annoys us, the neocortex is responsible for our ability to withhold our feelings, because we manage to consider the consequences of our actions. What creates the instant impulse to speak our mind is a mix between the reptilian and limbic system.

Challenges

Throughout the years, due to more advanced technology, subsequent research revealed that MacLean’s basic premise has several nuances. Therefore, his theory that these almost independent brain systems were added by accretion over the course of evolution was mainly mistaken. Instead, these structures have adjusted in inconsistent ways in different descendants. There are non-mammal species that do have a limbic system, but it is very underdeveloped, just as there are non-human mammals that have a neocortex, even some prefrontal cortex.

Understanding common behavior

Interacting with pets

Buying/adopting a new companion might have a significant impact on us, regardless of our stage in life. However, there is a great difference to be considered between common domestic animals and reptiles.

If we consider dogs, for example, they build a strong relationship with the owners, they love their humans and cravetheir attention. All of them suffer up to a certain degree and experience stress related to being separated from their owner, who is a unique person from whom it seeks comfort, security and reassurance.

On the other hand, a turtle, for instance, is a low-commitment pet. Unlike mammals, these species have retained their primitive characteristics, so most of their life is about basic necessities. Therefore, we might take their cold-hearted attitude very personal, feeling disappointed or even helpless in creating a bond with them.

As mentioned above, the explanation for these differences is that in reptiles the brain structure, i.e. the limbic system, that can enable them to share these feelings with humans, or any other creature, is underdeveloped. It’s not something they don’t want to do, it’s simply something they can’t do, due to a biological flaw.

Facing threats

When we experience fear, our body can react in very unexpected ways: crossing paths with a snake can make us instantly jump or run, moments before we manage to process what we have seen. What triggers this is a mixbetween our two primitive structures, i.e. reptile and limbic, that have learned over the past hundreds of million of years to act and save our lives. In this particular case, the snake is something we are programmed to fear, as of many other things that have killed our ancestors. Basically, some lines of code were written, that have become a genetic inheritance for a large part of us.

False alarms

On the same note, we often read or hear a message saying the popular phrase ‘we need to talk’ and start assumingthe worst, or interpret a message like ‘when are you getting home’ as controlling or even possessive. When we go through several negative emotional experiences, our limbic system, that has a memory of its own, makes this association between the visual stimulus of the message it receives with its aftermath, and it does it unconsciously. Therefore, when encountering similar signals, it manages to divert our attention, make us feel angry and slow down our perception at the flick of a switch, even though our neocortex would have a clear interpretation of that specific scenario.

Our brain can’t tell the difference between life-and-death situations (e.g. meeting a venomous snake), and a much less dangerous one (e.g. a changed deadline). There are several studies that compare MRI scans monitoring which areas in our brain are activated when we experience unpleasant events like: a minor downfall, receiving the wrong order, etc., and when we are facing dangerous threats. If we don’t take into consideration the intensity of our emotions, these results are similar. This finding can be a double-edged sword: it’s good for survival because we have this powerful firewall that never wears out, but could be awful for collaboration and coexistence, as we may make each other feel threatened unintentionally.

Useful tips & tricks

Just because we can’t change the way we were biologically built and evolved, it doesn’t mean that we can’t make use of several life hacks to improve the way we communicate.

Firstly, it’s advisable to plan any important or difficult conversation beforehand, whether that is with our partner, boss or colleague, teacher or parent, etc., for a moment when our neocortex is strong enough to keep up, and we don’t run out of mental energy. During the day our mind gets tired just as much as our body, so the evolved structure in our brain may be too weakened to withstand for long in the evenings. We are always ready to jump when we see a snake in the forest, but we are not always ready to solve equations, or have the required patience in an argument.

Secondly, if we get to that critical point when our pulse increases, we are breathing harder, those are strong indicators that the part of us that knows survival has started to take control. In that moment, stepping back and taking a break is essential.

We need to calm down and start moving towards emotional balance, and only afterwards we can resume those activities that require higher brain functions.

What to keep in mind

In spite of the recent findings, Paul MacLean’s theory can be interpreted as a beautiful metaphor that explains the way our mind works.

On that account, it’s essential to become aware that we basically have three voices in our head: one that knows how to communicate with words — the neocortex, and the other two that know how to communicate with moods and sensations — the limbic and reptilian structures. While the neocortex seeks our well-being, the limbic and reptilian systems seek to prevent our distress, which is an important difference.