Beyond the “Lizard Brain”: A New Perspective on Fear and Healing

We often hear about the “lizard brain” in psychology and personal development circles, that primitive part of our brain responsible for fight-or-flight responses. But this popular metaphor misses something crucial: the deeply human, historically informed nature of fear, especially for those whose ancestors have experienced generational trauma.

Navigating being a Black woman in North America is more complicated than labeling my experience as lizard brain.

While psychologists and personal development leaders commonly refer to the amygdala as our “lizard brain,” Tara Brach reminds us in her book Radical Acceptance that the complex interaction between cognition, memory, and affect creates the emotion of fear uniquely in mammals. This almond-shaped organ isn’t just primitive wiring—it’s sophisticated survival equipment embedded in our DNA, shaped by our collective histories.

In wellness workshops, I’ve repeatedly heard speakers discuss neurological fears tied to prehistoric dangers, running from sabertooth tigers being the classic example. But for many of us, especially those from historically marginalized communities, fear isn’t a distant evolutionary memory. It’s visceral, real, and recent.

For Black Americans like myself, that fear comes from surviving the Middle Passage, enslavement and its rape culture, Jim Crow segregation, and the continued reminders of vulnerability through figures like Leonard Deadwyler, Ron Settles, James Byrd, Tamir Rice, Eric Garner, Philando Castille, Breonna Taylor, Sandra Bland, and George Floyd. Unfortunately, the list continues to grow. Sometimes, danger isn’t an abstract concept, but it feels like it’s waiting around the corner.

When fellow changemakers, healers, and coaches casually dismiss these legitimate responses as “lizard brain” reactions, they inadvertently strip away historical context and deny the very real human experiences that shape our nervous systems. This framing lacks both compassion and cultural competence.

The Truth About the Amygdala: More Than Just Fear

To label the amygdala as the brain’s fear button or “reptilian core” is not just overly simplistic, it’s scientifically outdated.

The amygdala is indeed central to processing fear and triggering fight-or-flight responses. But recent neuroscience shows it plays many other roles, especially those tied to being emotionally and socially human. It’s not just about fear of tigers or trauma—it’s also involved in how we build trust, interpret facial expressions, remember emotional experiences, and navigate uncertainty.

Here are some key functions of the amygdala that reshape the “lizard brain” story:

• Social Awareness: The amygdala helps us recognize emotion in others’ faces, making it essential for empathy and belonging. Šimić et al., 2021

• Emotional Memory: It strengthens our memory of emotional events, helping us learn from past danger and joy. LeDoux, 2003

• Reward and Pleasure: It activates not only during fear, but also when we experience love, reward, or connection. Mirolli et al., 2010

• Risk Assessment: It’s part of the brain’s system for evaluating whether a situation is safe, risky, or ambiguous. LeDoux, 2012

• Chronic Stress and Anxiety: The amygdala also plays a role in sustained anxiety, which is especially relevant for people living under systemic threat. Davis et al., 2010

In short, the amygdala is not reptilian—it’s relational, emotional, adaptive, and human.

This organ doesn’t just react—it learns. It encodes patterns based on our lived experience, including those shaped by racism, generational trauma, and systemic threat. And importantly, it can change.

The Science of Healing: Insights from Epigenetics

Fortunately, emerging science offers transformative hope. Through epigenetics, the study of changes in gene expression rather than the genetic code itself, we’re discovering that we aren’t permanently bound by our histories or trauma responses.

This science isn’t just theoretical, it’s been observed in real-world history. During the final year of World War II, Nazi forces imposed a brutal blockade on the Netherlands in what became known as the Dutch Hunger Winter. Thousands died from starvation, and millions more endured extreme famine. In the years that followed, researchers discovered that the children—and even grandchildren, of survivors had significantly higher rates of chronic health issues such as diabetes, hypertension, and even schizophrenia. These findings suggest that the trauma of famine wasn’t just remembered psychologically, it left a biological imprint, passed through generations.

Neuroscientist Dr. Bianca Jones Marlin’s groundbreaking research illuminates the transgenerational impact of trauma. Her studies demonstrate that trauma can leave epigenetic markers on DNA that are then passed down to subsequent generations. Using rodent models, Dr. Marlin’s lab has shown that when parent mice are exposed to specific stressors, their offspring exhibit heightened sensitivity to related stimuli, despite never having encountered these stressors themselves. This suggests that our ancestors’ experiences can prepare us for similar environmental challenges through biological adaptations.

But here’s the crucial finding: these epigenetic markers are not permanent.

Dr. Marlin’s work reveals a powerful truth: gene expression can change when the environmental conditions that activate these markers are removed, or when positive interventions are introduced. In other words, healing is possible, and the epigenetic “switches” tied to trauma can be turned off. This finding underscores the potential for growth and resilience at an individual and collective level.

Rewiring for Growth

It’s not all bad news.

The implications of this research are profound. Through deliberate actions, whether mindfulness practices, therapy, or community initiatives, we can not only heal ourselves but also mitigate the transmission of trauma to future generations. The process involves creating environments that foster safety, connection, and understanding, allowing the body and mind to shift away from survival-based patterns into ones rooted in growth and possibility.

Research consistently shows that specific epigenetic modifications occur in brain cells as cognitive skills, such as learning and memory, develop. Repeated activation of brain circuits dedicated to learning and memory through environmental interaction can create lasting change. In essence, we can form new habits that train our brains and gene expression, allowing us to reshape our automatic responses.

This science of neurogenetics and epigenetics offers a profound message: transformation is possible. However, this healing journey must be approached with cultural humility and historical awareness.

Toward Healing with Context and Compassion

True healing begins at the individual level, extends to families, and ultimately transforms communities. By recognizing the unique nature of each person’s fear responses—not as primitive reptilian reactions but as sophisticated, historically informed adaptations—we create space for authentic growth and collective healing.

The path forward isn’t about suppressing our so-called “lizard brains.” It’s about honoring our complete human experience, acknowledging historical context, and embracing the remarkable plasticity that allows us to write new chapters in our personal and collective stories.

Dr. Marlin’s research confirms what many healers have intuited: we can change not just our own lives but potentially the biological legacy we pass on to future generations.