Pick up a stone from any beach and turn it in your hand. Notice its shape, its smoothness, the way light catches the striations of mineral deposits laid down perhaps millions of years ago. This stone remembers what shaped it—the volcanic heat that transformed its original composition, the glacial movements that carried it across continents, the endless rhythm of water that smoothed its rough edges over millennia. The stone cannot forget these forces. They are not memories to be recalled or dismissed; they are the stone itself, written into its very structure.

We are not so different.

The research on adverse childhood experiences has made this undeniable—indeed, it stands among the most consistent findings in medical and psychological research. In the original ACE study, researchers found that childhood adversity creates biological and psychological vulnerabilities that persist across the entire lifespan, dramatically increasing the risk of addiction, mental illness, chronic disease, and early death. The relationship follows what researchers call a “dose-response” pattern: the more adverse experiences in childhood, the higher the risk of problems later. One adverse childhood experience doubled the risk of alcoholism. Two quadrupled it. Four or more meant a person was seven times more likely to struggle with alcoholism and ten times more likely to inject drugs.

In Canada, 62% of people report at least one adverse childhood experience. Twenty-six percent experienced physical abuse. Twenty-two percent witnessed intimate partner violence. Four or more ACEs creates two to three times the risk of chronic disease.

Developmental resonance extends beyond individual family experience. Trauma resonates across generations through families, communities, and cultures. In Canada, this is inseparable from the legacies of colonization, residential schools, the Sixties Scoop, and ongoing systemic harms. Indigenous peoples carry specific burdens that non-Indigenous practitioners must acknowledge and understand. Over 150,000 children attended residential schools between 1831 and 1996. Over 4,000 confirmed deaths, with thousands more undocumented. Residential school survivors show three times higher PTSD rates. Indigenous youth suicide is five to eleven times higher than non-Indigenous youth.

Healing is not only individual—it is collective and cultural.

Developmental Stages and Vulnerabilities

The resonance layer also includes specific developmental stages, each with its own potential vulnerabilities:

  • Existence and Belonging (second trimester to three months): The infant learns whether their presence is welcomed, whether arriving feels safe, whether their existence is validated. Disruption creates profound uncertainty about the right to exist at all.
  • Need Fulfillment (one to eighteen months): The infant learns whether reaching brings response, whether needs are acknowledged, whether vulnerability is safe. Disruption creates the sense that needs are futile or burdensome.
  • Autonomy (eight months to two and a half years): The child explores independence while maintaining connection. Disruption creates either clinging dependency or counterdependent isolation.
  • Will and Power (two to four years): The child learns whether saying “no” is respected, whether they can have power while maintaining connection, whether agency means losing love.

These windows of vulnerability, rather than deterministic stages that lock people into fixed outcomes, are periods during which the nervous system is particularly plastic, particularly shaped by the environment it encounters. The patterns established during these windows persist—not as destinies, but as dispositions. Like the stone shaped by ancient forces but still responsive to today’s waves, we carry our developmental history while remaining capable of change.

Response: The Body’s Survival Wisdom

When threat exceeds capacity to cope, the nervous system doesn’t wait for conscious deliberation. It acts. Milliseconds before we can think about what to do, the body has already begun to respond. These are ancient survival mechanisms, refined across millions of years of evolution, designed to keep us alive when something goes wrong.

The most familiar responses are flight and fight. When threat is detected and action seems possible, the sympathetic nervous system activates. Heart rate increases. Breathing quickens. Blood flows to large muscle groups. The body prepares to run or to attack—whichever seems more likely to ensure survival.

But flight and fight require resources that aren’t always available. What happens when the threat is inescapable? When you can’t run and you can’t win a fight? This is where freeze enters. The nervous system shuts down: metabolic processes slow, pain perception changes, consciousness narrows or dissociates. You’re still alive but barely here. In nature, animals freeze when caught by predators, playing dead in hopes the predator will lose interest. In humans, freeze activates when threats are truly inescapable—the infant who cannot flee the neglectful caregiver, the child who cannot fight the overwhelming parent, the person trapped in a situation with no apparent exit.

There’s also the orient response—a state of perpetual scanning, constant readiness, hypervigilance. The nervous system is mobilized but not yet committed to fight or flight. It’s waiting, watching, trying to detect which direction the threat will come from. For some people, this becomes the dominant mode: never settled, never at rest, always anticipating the next danger.

These responses are the exquisite adaptations of a body that has learned to protect itself. The difficulty arises when the response locks in place, when it persists long after the original threat has passed, when it becomes the default mode of engaging with a world that may no longer pose the same dangers.

The Statistics of Trauma

In Canada, 64% of people have been exposed to at least one traumatic event. Eight percent report moderate to severe PTSD symptoms. Thirteen percent of young adults report PTSD symptoms. The numbers are higher among those with multiple trauma exposures: 26% of people with five or more exposures have PTSD, compared to 7% of those with only one.

These statistics represent millions of nervous systems organized around survival responses that were once necessary but now create suffering. The challenge is helping the body learn that the conditions have changed.

Continue to Adaptation and Addiction to learn what happens when acute responses become chronic patterns—and why there is hope for change.