Have you ever wonder why you get so easily triggered, defensive, or anxious over everyday stressors?
Blame it on the “lizard brain.”
As the oldest structural part of our evolutionary history, the reptilian brain (or R-complex) is hardwired for one primary job: keeping you alive.
But when this ancient survival mechanism takes over in modern life, it can trigger unhelpful fears, rigid routines, and impulse reactions.
Let’s dive into how the reptilian brain operates, the behavioral traits it creates in humans, and how you can tame your primitive instincts using conscious awareness.
(Disclaimer: This article is for informational purposes only. It is not meant to treat or diagnose anyone.)
Are There Reptilian Brain Behaviors in Humans? This article discusses the R-Complex and how humans exhibit this behavior.
We have a body, but where is the user manual?
I started my personal growth journey in 1997, and the first area I studied was psychology and the mind.
I noticed how easily I was triggered (an unconscious emotional reaction) as a child and young adult, before the term ‘triggered’ was even used, and I believe what gets triggered in us is the R-complex part of the brain.
Advertisers and other media outlets know this, so most media is fear-based because it gets people’s attention.
What is the Reptilian Or Lizard Brain?
The “reptilian” or “lizard” brain is part of the Triune Brain model proposed by American neuroscientist Paul MacLean in the 1960s.
In MacLean’s triune brain model, the basal ganglia are considered the reptilian, or primal, brain.
This structure controls our innate, automatic self-preserving behavior patterns, ensuring our survival and that of our species.
Three primary brain structures developed sequentially, from oldest to newest, as shown below.
- The basal ganglia are found at the center of the human brain =The R-Complex.
- The limbic system of the brain (which consists of various component structures, such as the amygdala and hippocampus)
- The neocortex (which is implicated in conscious thought, language, and reasoning).
MacLean, within the Triune brain model, suggested that the basal ganglia and several nearby structures at the base of the forebrain are responsible for species-typical behaviors, including aggression, dominance, territoriality, and ritual displays.
The Reptilian Brain consists of the upper part of the spinal cord, the basal ganglia, the diencephalon, and the midbrain regions—all of which sit atop the spinal column like a knob in the middle of our heads.
This part of the brain fundamentally influences our behavior and controls bodily functions essential for sustaining life, such as breathing and body temperature.
The Reptilian Brain, or R-complex, is also where repeating patterns such as:
- rituals
- automatic responses without conscious thought
- predictability
- fear of losing a job, spouse, home,
- fear of dying,
- lack of money & resources,
- and the unknown are all anxiety and trauma responses.
I’ve always admired people willing to take a leap of faith and go for it, like quitting their job and moving to another country.
Once people fear not surviving, the cerebrum fear center takes over, and we are at the mercy of its reactions to perceived threats. The news media targets this part by telling us about the latest tragedies or economic woes. (1)
The key functions of the reptilian brain in humans
The brain structures once referred to as the reptilian brain do serve important functions:
- The brainstem and basal ganglia, which were previously associated with the reptilian brain, help control vital functions such as heart rate, blood pressure, breathing, and body temperature.
- The basal ganglia play a crucial role in voluntary movement control, motor learning, and coordination.
- These structures are involved in the development and execution of habitual behaviors.
- Contrary to the outdated triune brain model, these “ancient” brain structures contribute to emotional experiences and regulation, working in conjunction with other brain regions.
- The basal ganglia are involved in aspects of decision-making and even higher-order cognitive functions like self-control.
- While not exclusively responsible for “primitive” behaviors, these brain regions do contribute to innate self-preserving behaviors and responses to potential threats.
- The basal ganglia are part of the brain’s reward system, influencing motivation and reinforcement learning.
These functions are not isolated to the reptilian brain but are integrated with other brain regions in complex neural networks.
Modern neuroscience emphasizes the interconnected and cooperative nature of different brain structures, rather than viewing them as separate evolutionary layers. (2)
Why We Have A Lizard Brain: We must first look to our evolutionary past
I. Evolutionary Roots: Reptile Behavior in Humans
To understand the R-complex part of the brain in humans, we must first look to our evolutionary past. Humans share a common ancestry with reptiles, and certain behaviors have persisted across millions of years.
The survival instincts of our reptile forebears, such as fight-or-flight brain responses, territoriality, and social hierarchies, are deeply embedded in our genetic code.
II. Unveiling the Reptilian Brain in Humans
- Anatomy and Function: The reptile part of the brain comprises the stem and the cerebellum, governing fundamental functions like breathing, heart rate, and balance. It is the oldest part of the brain, responsible for basic survival instincts and involuntary responses.
- Fight or Flight: One of the most well-known aspects of the reptilian brain is its role in the fight-or-flight response. When faced with danger, triggers cascade physiological reactions designed to enhance our chances of survival.
- Territorial Instincts: The reptilian mind also influences our territorial instincts, contributing to the formation of personal boundaries and the defense of resources. This behavior can be observed in various aspects of human life, from individual spaces to geopolitical conflicts.
III. Human Reptile Brain in Modern Society
- Decision-Making and Risk Aversion: Despite the evolution of more advanced structures, the reptilian brain plays a significant role in decision-making. Humans often exhibit risk aversion, a trait inherited from our reptile ancestors who needed to carefully assess threats in their environment.
- Social Hierarchies: The reptilian brain establishes social hierarchies, a phenomenon seen in various human interactions. Individuals in the workplace and in social circles may display dominant or submissive behaviors influenced by these ancient instincts.
IV. Overcoming the Limitations of the Lizard Brain
- Emotional Regulation: Understanding the influence of the reptile-like part of the brain allows us to work towards emotional regulation. Techniques such as mindfulness and cognitive-behavioral therapy can help manage instinctual reactions to stressors.
- Evolutionary Advancements: While the reptilian brain provides a foundation for survival, the evolution of the human mind has introduced more complex cognitive functions. Developing higher-order thinking and emotional intelligence can help override primitive responses in modern situations.
Systems Controlled & Influenced By The Reptilian Brain
- Education System
- Government
- Military
- Judicial
- Religion
- Business
When the Reptilian brain controls someone, their behavior can affect other people’s brain responses.
We can be calm, relaxed, and collected for one minute. Still, if someone displays serpentine brain behaviors in our presence, it can affect our behavior unless we remain conscious.
The desire to control, whether in relationships, circumstances, or life, is a primary trait of the Reptilian Brain in action. We often call people displaying this behavior control freaks, and freak-like is what they appear to be.
Reptilian Brain Behavior Traits
Below are typical reptilian brain behaviors.
- Territoriality
- A hierarchical structure of power
- Control
- Ownership
- Wars
- Jealousy
- Anger
- Fear
- Hostility
- Worry
- Stuck or frozen with fear
- Addictions
- Anxiety
- Aggressiveness
- Conflict
- Extreme behavior
- Competitiveness
- Cold-blooded
- Dog-eat-dog beliefs, might is right, and survival of the fittest.
- OCD, hoarding, looting,
- Superstitions
- Deception
- Fight, flee, or freeze – (fight or flight response)
- Obesity from fear of lack of food – (food scarcity)
- Daily rituals, ceremonial re-enactments.
- Hunger
- Sex
- Habits/Automatic Routines
The R Complex can overpower the ability to have calm and rational thoughts.
These traits all stem from a belief of insufficient or a ‘lack of’ mentality. It’s all about survival.
Emotional responses are based on the fear of not surviving, so marketers and news outlets always use fear to get you to watch or buy the product.
Power, status, reputation, and sense of self. It doesn’t like change or new viewpoints.
That is why enacting any real difference in politics seems nearly impossible. It fears change, and any real policy change can be an absolute nightmare to enact.
With new views in science, politics, religion, education, and medicine, the reptilian brain sees this as a threat and will always defend itself. Consciousness always wins in the long run, but not without taking out a few casualties.
It doesn’t know the difference between real and imagined, and its thoughts about events are just as accurate as those of the “real thing.” Anxiety is a state caused by the R Complex brain that should cause us to feel anxious even when nothing is happening.
There is a gnawing away in the belly that something bad will happen, and it doesn’t like surprises either.
What Part Does The Amygdala Play In The Limbic System?
The amygdala is your brain’s alarm system. Its job isn’t to think—it’s to decide, fast, whether something is a threat, an opportunity, or emotionally important.
The Amygdala is one of two almond-like groups of cores found deep in the brain and in the middle of the mind’s transient flaps.
It’s used for essential jobs like handling memory, basic leadership, and emotional reactions such as fear, anxiety, and anger.
The Amygdala is a significant aspect of the limbic system. (3)
Here’s the simplest way to think about it:
Imagine the limbic system is the emotional operating system of your brain. The amygdala is the smoke detector.
- See a snake? The amygdala fires before you consciously process it.
- Hear someone insult you? Amygdala flags it as emotionally significant.
- Experience something amazing or terrifying? The amygdala tells your brain, “Remember this.”
This is why it matters:
If your amygdala is running the show, you’re reacting instead of responding. Fear, anger, anxiety—they’re all amplified because the alarm is driving your decisions.
The prefrontal cortex (the rational part of your brain) is the CEO. The amygdala is the security guard. A good security guard warns the CEO. A bad one pulls the fire alarm every five minutes.
High performers don’t eliminate the amygdala—they train themselves to pause long enough for the CEO to make the decision.
The amygdala’s role in the limbic system is to rapidly detect emotional significance—especially threats—trigger survival responses, and strengthen emotional memories. It’s essential for keeping you alive, but if it’s overactive, it can keep you from making your best decisions.
The Function of the Reptilian Brain is to Serve You
The primary function of the R Complex brain is survival and the ability to keep us alive. Without this body program, we wouldn’t last very long here on earth, so there is no sense in beating it.
The problem arises when you stay stuck in survival mode as a way of being. You become locked in the R-complex and will perceive reality as a fight for survival.
This part of the brain could be seen as primitive, which isn’t helpful in our modern world.
Everything suddenly seems like a threat to your survival. We become reactive, suspicious, paranoid, and delusional.
Use your conscious awareness to live your life and keep your survival brain a secondary backup, but not a primary leader, except only when entering new or unfamiliar situations.
The Survival part of your brain is your friend. However, it is continuously triggered by exposure to negative media, people, and situations.
This is why periodically getting out into nature and away from stress is the key to maintaining your emotional health.
The R-complex brain is programmed to reject the unfamiliar and trap us in our comfort zones – where less energy is spent and less risky action is taken, which made perfect sense back when we were running from hungry saber-toothed tigers.
But today, in an age where constant personal growth, self-experimentation, and new ways of thinking are critical to our success and happiness? Not so much.
Consciousness is one way to be free from the effects of the reptilian brain
Which means knowing the difference between real and imagined. Imagination is a beautiful tool, but it can also create “doomsday” scenarios in our minds.
Remain conscious of your thoughts, and when you get unsettling feelings in your body, focus on what ideas you have been having. Redirect them to beliefs that make you feel good and empower you.
The R-complex continuously responds to thoughts as if they are happening in ‘real-life.’
Eckhart Tolle has many great tips and advice for dealing with repetitious thinking and being present with yourself. The first way to overcome the Reptilian Brain is to become aware of when it has overtaken you.
An unhealthy lifestyle like eating junk foods and getting inadequate rest will cause the reptilian brain to go into overdrive.
Many people have adopted this ‘hustle’ mentality, which means working 80 hours or more a week, which leads to burnout and adrenal exhaustion.
We need to get back to basics. Work, rest, take a hot bath or shower, play, take your vitamins, help others, get a massage, return to your spirituality, and take care of your responsibilities. Life is a journey, so have fun.
Why Am I Telling You This?
When you see these characteristics in yourself or others, don’t be judgmental; instead, recognize them for what they are — part of the human body and experience of being human.
Before discovering the Lizard Brain, I knew something was off about these traits when I saw them displayed.
Now that we are all aware of the R Complex, let’s bring conscious awareness back into the picture to reduce or eliminate the destructive nature of the ‘fear-based’ creations.
Part of the changes we all will experience when the “shift” occurs is that the R-complex will cease to control and influence us.
It will feel as if a significant burden has been lifted from our shoulders. Author David Icke described an excellent example of reptilian behavior in people.
He says people dominated by the reptilian brain want to know the football game’s score before it even starts because they can’t handle the discomfort of the uncertainty of the outcome.
The lizard brain hates surprises and needs to know; it requires certainty of what will happen next.
The best antidote for reptilian behavior is emotional control. When emotions get out of whack, the R-complex will soon command the body, and then all hell breaks loose.
The world does not need this, and she needs her people to get some emotional control.
If you want an easy way to calm the reptilian brain, try meditation, eating healthy, whole foods, avoiding processed foods, and avoiding stimulants.
The Sympathetic nervous system/ego controls the R-complex and triggers our fight-or-flight response system. I believe this is the key to overcoming the adverse effects of the Reptilian Brain.
Breathing exercises, physical exercise, and a good night’s sleep can help keep your nervous system healthy.
Overcoming Lizard Thinking And Reacting For Personal Growth
Your mind doesn’t rise to your goals. It falls to your conditioning.
Most people think they’ll make better decisions when life gets easier. That’s backwards. You’ll make better decisions when you’ve trained yourself to think better under pressure.
Your lower instincts want immediate relief:
- Scroll instead of reflect.
- React instead of respond.
- Quit instead of persist.
- Chase comfort instead of growth.
Your higher mind plays a different game. It asks, “What’s the best decision, not the easiest one?”
That’s a skill. And like any skill, it gets stronger through repetition.
Think of your mind like a muscle. Every time you pause before reacting, you’re getting stronger. Every time you keep a promise to yourself, you’re building trust. Every time you choose discipline over impulse, you’re rewiring your default behavior.
This is where practices like meditation, journaling, prayer, and quiet reflection become powerful. They’re not just “feel-good” habits—they’re reps. They train your ability to notice your thoughts without letting them control you.
The person who masters their emotions doesn’t have fewer emotions. They simply stop letting every feeling dictate every decision.
Here’s the irony: the more control you gain over your mind, the more freedom you experience.
Because freedom isn’t doing whatever you feel like doing. That’s impulse.
Freedom is having the ability to choose what matters most—even when your emotions are pulling you somewhere else.
The goal isn’t to silence your instincts. They’re there to protect you. The goal is to make sure they’re taking advice from your highest values instead of making every decision on their own.
That’s when you stop living on autopilot.
That’s when you start leading your life instead of simply reacting to it.
Daily Practices to Tame Your Inner Lizard
Your brain doesn’t care about your goals. It cares about keeping you alive.
That’s why, when things get hard, your first instinct is usually to avoid, escape, or react. The problem is, the habits that helped humans survive thousands of years ago often hold you back today.
The solution isn’t to fight your instincts. It’s to train them.
Here are six daily practices that help you stop living on autopilot and start living with intention.
Pause Before Reacting
Most bad decisions happen because they happen too fast.
Someone criticizes you? You snap back. A problem shows up? You panic. Things don’t go your way? You quit.
Instead, build the habit of pausing.
A few deep breaths or even five seconds of silence is often enough to let your rational mind catch up with your emotional one. That pause is where better decisions are made.
Observe Your Emotions Without Becoming Them
Just because you feel something doesn’t mean you have to become it.
Feeling angry doesn’t make you an angry person. Feeling afraid doesn’t mean you’re in danger.
Your emotions are signals—not commands.
Learn to say, “I’m noticing anxiety,” instead of, “I am anxious.” That small shift creates distance between you and your emotions, giving you the freedom to choose your response.
Practice Compassion
Fear makes people defensive. Compassion makes them strong.
When you stop assuming everyone is against you, you stop wasting energy protecting yourself from battles that don’t exist.
Practice extending grace—to yourself when you make mistakes and to others when they fall short. Compassion doesn’t make you weak. It keeps your emotions from controlling your actions.
Limit Fear-Inducing Media
Your brain wasn’t designed to process a constant stream of outrage, conflict, and bad news.
If the first thing you consume every morning is fear, don’t be surprised when fear shapes your day.
Protect your attention like it’s your most valuable asset—because it is.
Choose information that helps you grow instead of content that keeps you emotionally hooked.
Connect With Nature
Nature has a way of reminding you that not everything is urgent.
A walk outside, sunlight on your face, fresh air, or sitting quietly beneath a tree can interrupt the cycle of constant stimulation.
When you slow down, your nervous system follows.
Sometimes the fastest way to calm your mind is to step away from the noise.
Prioritize Sleep and Exercise
You can’t expect to make great decisions with an exhausted brain.
Poor sleep makes you more reactive. A sedentary lifestyle drains your energy and resilience.
Exercise teaches your body to handle stress. Sleep allows your brain to recover, regulate emotions, and prepare for another day.
Think of them as non-negotiables—not because they’re trendy, but because they’re the foundation of clear thinking and emotional control.
The Bottom Line
You don’t overcome your “inner lizard” with one big breakthrough.
You do it through small, consistent choices repeated every day.
Every pause before reacting, every act of compassion, every walk outside, every workout, and every good night’s sleep is another vote for the person you’re becoming.
Because transformation isn’t about changing who you are overnight.
It’s about teaching your instincts to serve your purpose instead of your fear.
Conclusion
The goal isn’t to eliminate your survival instincts—they’re essential. The goal is to recognize when they’re no longer serving you and consciously choose wisdom over impulse, love over fear, and growth over comfort.
Personal and spiritual development isn’t about becoming someone else; it’s about becoming less controlled by automatic reactions and more guided by intentional awareness.
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