The wound is not always where we think it is.
When we think of trauma, we often imagine painful memories, intense emotions, or difficult events from the past. For a long time, psychology focused almost exclusively on this narrative dimension: what happened, how it was experienced, and how it is remembered.
Research in recent decades has begun to reveal something deeper. Trauma functions as a biological state, in addition to being a memory. And when that state persists for months or years, it ceases to be a temporary reaction and becomes a reorganization of the entire organism.
The wound is also what the body had to remain after the event ended. The nervous system registers survival conditions. When survival becomes the norm, every biological system adapts at that cost. Even the smallest structures in our cells. Even the mitochondria.
Mitochondria do much more than produce energy
For years, mitochondria were taught as simply the powerhouses of the cell. The picture was straightforward: mitochondria produce ATP, the molecule that provides energy for the organism to function. That view is now remarkably incomplete.
Mitochondria are involved in regulating inflammation, immunity, metabolism, stress response, programmed cell death, neuronal plasticity, and communication between biological systems. They function as extremely sophisticated sensors of the internal environment.
They constantly listen to what's happening in the body. They listen to hormones. They listen to neurotransmitters. They listen to inflammatory signals. They listen to physiological states. And they adapt their functioning to what the body deems necessary to survive. That's why mitochondria occupy a privileged position to register the cumulative impact of chronic stress and trauma.
The body learns survival states
When a threat appears, the nervous system activates a cascade of responses designed to protect life. Adrenaline and cortisol levels rise. Breathing patterns change. Blood flow is altered. Energy is redistributed. Digestion slows. Vigilance increases. The entire organism reorganizes itself around one fundamental priority: survival.
This mechanism is remarkably effective when the threat is temporary. The problem arises when the danger disappears and the body continues to function as if it were still present. Then the survival state becomes a biological identity.
Neuroscientist Bruce McEwen (1998) described this phenomenon using the concept of allostatic load. Every adaptation has a cost. And when the body keeps systems designed to function for only hours activated for years, the biological price begins to accumulate.
How chronic stress reaches the mitochondria
The brain stores trauma as memory and also transmits it as a state. Every day. Every hour. Every minute. Through the autonomic nervous system. Through hormones like cortisol. Through neurotransmitters. Through inflammatory signals.
Cells constantly receive these messages, and mitochondria must respond to them. If the brain interprets the world as dangerous, cells must sustain a different energy demand. More vigilance. More mobilization. More repair. More resources dedicated to survival.
Over time, this demand profoundly alters mitochondrial function. Psychobiologist Martin Picard (2018), from Columbia University, along with McEwen, developed the concept of mitochondrial allostatic load: the idea that chronic psychological stress translates into measurable structural and functional changes within the mitochondria. This is not because the mitochondria store traumatic memories, but because they adapt their structure and behavior to the repeated demands of the internal environment.
When the form changes, the function changes.
One of the most fascinating discoveries in modern cell biology is that mitochondria are not rigid structures. They constantly change shape. They fuse. They divide. They reorganize. They modify their internal architecture according to the metabolic needs of the cell.
Within each mitochondrion lies a complex network of folds, the mitochondrial cristae. These folds organize the processes that convert oxygen and nutrients into usable energy. They function as fundamental structures for energy efficiency, playing a role far greater than that of a mere anatomical detail.
Research from the laboratory of Martin Picard, trained by Douglas Wallace at the Center for Mitochondrial Medicine at the University of Pennsylvania, has shown that prolonged stress can disrupt the organization of these structures. When the internal architecture loses efficiency, the cell needs more resources to produce the same amount of energy. The organism works harder to obtain less.
When trauma returns in the form of fatigue
Many people expect trauma to resurface as memories. Sometimes it returns as exhaustion. As brain fog. As a persistent feeling of tiredness. As difficulty recovering from what were once normal efforts. As restless awakenings. As a hard-to-explain feeling of having aged too quickly.
Emerging research on psychobiology and metabolism suggests that some of these experiences may be related to physiological adaptations accumulated over years of chronic activation. The event may have ended, but the adaptation may still be at work. The nervous system may still be sending threat signals. And the mitochondria may still be organizing their functions around those signals.
Inflammation, energy, and perception
The relationship between trauma and mitochondria affects physical energy and perception. Inflammation alters brain function, modifies neurotransmitters, affects mood, influences motivation, reduces cognitive flexibility, and increases sensitivity to stress.
Psychiatrist Charles Raison has shown how inflammatory processes can contribute to depressive symptoms, persistent fatigue, and cognitive difficulties. The subjective experience of the world is also affected by these biological adaptations. An exhausted person thinks differently, perceives differently, interprets differently, and feels differently.
Adaptation, not cellular memory
It's important to avoid oversimplification. Current scientific evidence does not support the idea that mitochondria store traumatic memories. Trauma is stored in them as a hidden archive only in metaphorical language, not in actual biology.
What happens is more complex. The repetition of physiological states generates physiological adaptations. The repetition of signals generates biological reorganization. The repetition of demands modifies entire systems. This is adaptation. And an adaptation sustained over years can end up appearing permanent.
Biology can also be reorganized
The same plasticity that allowed the body to adapt to stress is what allows it to recover. Mitochondria are extraordinarily dynamic. They respond to changes in the internal environment. They respond to sleep. To physical exercise. To emotional regulation. To stress reduction. To the quality of relationships. To physiological safety.
When the nervous system gradually stops sending constant threat signals, cells begin to receive different messages. And biology can reorganize itself around new conditions. Recovery includes remembering what happened and also providing the body with enough repeated experiences of safety so that it stops investing all its resources in survival.
The true scar of trauma
Perhaps one of the most important ideas that emerges from this new understanding is this: trauma is defined by what happened and also by the adaptations that the organism had to develop to move forward.
The true scar sometimes resides in the physiological state that has become normal, rather than in the memory. In the weariness that seems like part of one's personality. In the hypervigilance that appears to be prudence. In the tension that seems like identity.
Understanding this transforms our perspective on healing. The work shifts from focusing solely on changing thoughts or reinterpreting the past to restoring capacity. The capacity to rest. The capacity to recover. The capacity to feel safe. The capacity to live without every cell in the body constantly preparing for a threat that has already ended.
True recovery comes when the body stops organizing itself around survival and gradually returns to organizing itself around life.
Sources and references
McEwen, BS (1998). Protective and damaging effects of stress mediators. New England Journal of Medicine, 338(3), 171-179. Neuroscientist, researcher of the physiology of stress.
Picard, M. (2018). Mitochondrial psychobiology: Foundations and applications. Current Opinion in Behavioral Sciences, 28, 142-151. Psychobiologist, Professor of Behavioral Medicine in Psychiatry and Neurology, Columbia University.
Picard, M. & McEwen, B.S. (2018). Psychological stress and mitochondria: A systematic review. Psychosomatic Medicine, 80(2), 141-153.
Porges, SW (2011). The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-Regulation. WW Norton. Neuroscientist.
Raison, C.L. & Miller, A.H. (2017). Pathogen-host defense in the evolution of depression: Insights into the concept of psychiatric disorders. JAMA Psychiatry. Psychiatrist, researcher of the connection between inflammation and depression.
Van der Kolk, B. (2014). The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma. Viking. Psychiatrist, trauma researcher.
Wallace, DC (2013). A mitochondrial bioenergetic etiology of disease. Journal of Clinical Investigation, 123(4), 1405-1412. Geneticist, a leading expert in mitochondrial biology.