Zoe is one of many survivors who only remember an experience of sexual assault years after it happened, in what might be referred to as delayed recall (the term “repressed memories” is controversial among psychologists). It’s a form of dissociative amnesia, a disorder in which a patient doesn’t actively remember something traumatic that happened to them, usually because they detached mentally during the event as a coping mechanism. “Extreme, violent trauma, particularly repeated trauma, can produce markedly altered states of consciousness,” says Richard J. Loewenstein, MD, medical director of The Trauma Disorders Program at Sheppard Pratt Health System. “These include fight and flight, but also a ‘freeze’ state. People shut down, space out, their heart rate drops”—kind of like when a small animal plays dead around a large predator.
Because this state is similar to a dissociative state, things that happen when the brain is in it may not be readily accessible once the person returns to normal, says Dr. Loewenstein. (Research shows that if you get people drunk in a lab setting and teach them something, for example, they may not remember it when they’re sober. But when they’re drunk again, they do remember.) “This, along with other factors, may help explain lack of conscious recall of traumatic experiences.”
In Zoe’s case, her fear of the police officer, coupled with his direct questions about her attacker, may have put her brain back into the freeze state—and helped her remember her assault. Memory experts emphasize that these traumatic memories aren’t technically lost—they just haven’t been retrieved in a while. “Our brains encode and store things that have significance to us,” says Jim Hopper, PhD, a teaching associate in psychology at Harvard Medical School and an expert in recovered memories from trauma. “If we’re in a traumatized state, that amplifies the effect: Certain pieces get strongly encoded and strongly stored. But how well things get stored is entirely different from whether or not they get retrieved.” This is why Zoe remembers nothing else that happened on the day of her attack, but her memory of the attack itself is vivid; she just hadn’t accessed it until her police interrogation.