Why trauma changes how our memory engages with our conscious experience | Scientific American
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New Issue: Orbital Catastrophe Ahead? Read Now<br>August 22, 2026<br>5 min read<br>Add Us On GoogleAdd SciAm<br>Why trauma changes how our memory engages with our conscious experience
Trauma can distort how memories are stored and retrieved in the brain
By Michele Patterson Ford & The Conversation US
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When survivors of trauma recount their experiences, they are often questioned because of how they relay their stories. They may have problems remembering what happened, or their memories may be jumbled or even contradictory. People hearing those stories—attorneys, reporters, healthcare workers or friends—may expect a clearer, linear narrative.<br>Those unaffected by trauma may also be surprised to hear how the person acted in the moment. It’s easy to assume that someone experiencing a traumatic event would have a “fight or flight” response, instinctively fighting off a perpetrator or fleeing the scene—but that might not be the case.<br>Understanding the science of how trauma affects memory and behavior reveals why these responses can actually be expected and are not contradictory.<br>On supporting science journalism<br>If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.<br>In both my academic and clinical work as a psychologist, I have witnessed the impact trauma has on people’s memories and behaviors, especially when an event in their present life triggers something from their past.<br>Research shows that taking a trauma-informed approach, which prioritizes understanding and curiosity about someone’s experience as opposed to judgment or critical evaluation, increases empathy for survivors’ thoughts, feelings and behaviors.<br>How trauma affects the brain<br>According to the World Health Organization, approximately 70 percent of people worldwide report experiencing a traumatic event in their lifetime. The majority of these people do not develop PTSD, a clinical diagnosis of symptoms, such as having nightmares and flashbacks about the event, avoiding places that are reminders of it, and increased arousal that can make concentration and sleep difficult. Many survivors don’t meet criteria for PTSD but struggle with feeling distressed, depressed or anxious.<br>In traumatic situations, people often respond in unexpected ways, and they may second-guess themselves. This may happen particularly when someone experiences a repeated trauma, which is more likely than not due to how many people experience traumatic events.<br>Trauma also distorts how memories are stored and retrieved.<br>Research indicates that people experience traumatic memories differently than memories of other significant events, such as sad or positive experiences. Two of the main brain structures scientists believe are involved in storing traumatic memories are the hippocampus—responsible for memory storage—and the amygdala, which is responsible for processing emotions.<br>During trauma, the amygdala becomes highly active, processing emotions such as fear, and the hippocampus becomes overwhelmed by stress, leading to problems with memory storage.<br>Traumatic memories do not follow a neat, linear story. Instead, people may experience the memory as disconnected fragments of sensations, emotions, smells or images. Such memories cause the body to reexperience the past threat as if it is happening in the moment. This may cause a person to feel like running away or fighting back—flight or fight. Or they may freeze.<br>In other words, people don’t have the distant perspective they often feel with other memories from the past. Rather, they may feel they are reliving the original experience.<br>Misinterpreting victims’ behaviors<br>With this understanding, consider someone who experiences a trauma at the hands of a professional during an appointment. They may appear outwardly calm while it happens and then leave the session as they typically would—checking out, providing payment and possibly even scheduling the next appointment. While their response to act normally may seem odd, such behavior makes sense for someone trying to escape a threat.<br>Fight, flight or freeze responses have become widely known in popular culture. In a freeze response, a person’s mind goes blank and they may be unable to speak, leading to a “deer in the headlights” behavior.<br>On the other hand, a person may act paradoxically—perhaps by going on about their day as if nothing happened. They may not report the event or may question whether the incident even occurred. This represents another survival response—the lesser-known fawn response. This way of handling stress occurs when someone acts calm, appeases the threatening person and retreats to...