Sep 28, 2018 04:21 PM
https://blogs.scientificamerican.com/obs...t-victims/
EXCERPT: . . . I’m an expert on psychological trauma, including sexual assault and traumatic memories. I’ve spent more than 25 years studying this. I’ve trained military and civilian police officers, prosecutors and other professionals, including commanders at Fort Leavenworth and the Pentagon. I teach this to psychiatrists in training at Harvard Medical School.
As an expert witness, I review videos and transcripts of investigative interviews. It’s like using a microscope to examine how people recall—and don’t recall—parts of their assault experiences. I’ve seen poorly trained police officers not only fail to collect vital details, but actually worsen memory gaps and create inconsistences. Ignorance of how memory works is a major reason why sexual assault is the easiest violent crime to get away with, across our country and around the world.
[...]
Researchers divide memory processing into three stages: encoding, storage, and retrieval.
Encoding refers to the temporary registration of sensations and thoughts into short-term memory, a kind of “buffer” or RAM that can hold information up to 30 seconds. For any event we experience, including this one, we're not taking in every detail. From moment to moment, what our brain encodes is a function of what we're paying attention to, and what has emotional significance to us. [...] In contrast, what we're not paying attention to, or has little or no significance [...] are encoded poorly or not at all.
Critically, whether it’s an IED attack or a sexual assault, just because we—or an investigator, or even the survivor herself looking back later—believe some aspect of an event would or should be a central detail, that does not mean it was a central detail for the survivor’s brain at the time. Many who have been sexually assaulted don’t remember whether certain things were done to their body because, at that point, they were focused on the perpetrator’s cold eyes, or traffic sounds on the street below. That tells us nothing about the reliability of the details they do recall, and nothing about their credibility.
Storage is the next stage. [...] From the outset, storage of central details is stronger than storage of peripheral ones. Those peripheral details fade quickly, and if not remembered and re-encoded, are mostly gone within a day. We all know this: What we pay attention to and has significance to us is what we’re more likely to remember over time.
[...] Here’s another factor that affects storage strength: Whether a detail’s emotional significance to us is negative or positive. Evolution has selected brains that are biased to encode the negative more strongly, to enable survival in a world with predators and other grave dangers. [...] Most important of all, when it comes to what will remain stored in our brains, is this: How emotionally activated, stressed, or terrified we were during the experience. Decades of research have shown that stress and trauma increase the differential storage of central over peripheral details.
[...] Which brings me, finally, to memory retrieval. I only have time to say a few important things.
Yes, memories generally fade. That’s partly because what starts out as a relatively detailed memory becomes more abstract over time. We remember the gist of what happened and a few of the most central details. When we remember or tell the story, our brain is literally piecing it together on the fly. That’s another reason why, as memory researchers love to say, memory is not like a videotape. Sometimes we get confused. Sometimes other people, or even movies we watch, supply inaccurate details that are inadvertently re-encoded into the overall memory and its abstract story.
But memories of highly stressful and traumatic experiences, at least their most central details, don’t tend to fade over time. And while people may have the superficial abstract stories they tell themselves and others about their worst traumas, that’s not because the worst details have been lost. It’s often because they don’t want to remember them, and don’t (yet) feel safe to remember them.
[...] for many victims of sexual assault [...] They have bland abstract descriptions they tell themselves and others, for example, their husband early in the marriage, before they feel safe enough to share the painful details, and that sharing some of those is necessary for other reasons. They might not have retrieved the horrific central details for months or years. But that doesn’t mean those vivid sensory details and wrenching emotions aren’t still there, never going away, ready to be retrieved under the right (or wrong) circumstances.
Yes, peripheral and less central details can get distorted more easily than many people realize. But decades of research have shown that the most central details are not easy to distort, which typically requires repeated leading questions from people in authority or a very strong internal motivation for doing so. But without compelling evidence of such influences, there is no scientific or rational basis for assuming that such distortions have occurred, especially for those most central and horrible details the person has been both tormented by and trying to avoid, sometimes successfully and sometimes not, for years or even decades....
MORE: https://blogs.scientificamerican.com/obs...t-victims/
EXCERPT: . . . I’m an expert on psychological trauma, including sexual assault and traumatic memories. I’ve spent more than 25 years studying this. I’ve trained military and civilian police officers, prosecutors and other professionals, including commanders at Fort Leavenworth and the Pentagon. I teach this to psychiatrists in training at Harvard Medical School.
As an expert witness, I review videos and transcripts of investigative interviews. It’s like using a microscope to examine how people recall—and don’t recall—parts of their assault experiences. I’ve seen poorly trained police officers not only fail to collect vital details, but actually worsen memory gaps and create inconsistences. Ignorance of how memory works is a major reason why sexual assault is the easiest violent crime to get away with, across our country and around the world.
[...]
Researchers divide memory processing into three stages: encoding, storage, and retrieval.
Encoding refers to the temporary registration of sensations and thoughts into short-term memory, a kind of “buffer” or RAM that can hold information up to 30 seconds. For any event we experience, including this one, we're not taking in every detail. From moment to moment, what our brain encodes is a function of what we're paying attention to, and what has emotional significance to us. [...] In contrast, what we're not paying attention to, or has little or no significance [...] are encoded poorly or not at all.
Critically, whether it’s an IED attack or a sexual assault, just because we—or an investigator, or even the survivor herself looking back later—believe some aspect of an event would or should be a central detail, that does not mean it was a central detail for the survivor’s brain at the time. Many who have been sexually assaulted don’t remember whether certain things were done to their body because, at that point, they were focused on the perpetrator’s cold eyes, or traffic sounds on the street below. That tells us nothing about the reliability of the details they do recall, and nothing about their credibility.
Storage is the next stage. [...] From the outset, storage of central details is stronger than storage of peripheral ones. Those peripheral details fade quickly, and if not remembered and re-encoded, are mostly gone within a day. We all know this: What we pay attention to and has significance to us is what we’re more likely to remember over time.
[...] Here’s another factor that affects storage strength: Whether a detail’s emotional significance to us is negative or positive. Evolution has selected brains that are biased to encode the negative more strongly, to enable survival in a world with predators and other grave dangers. [...] Most important of all, when it comes to what will remain stored in our brains, is this: How emotionally activated, stressed, or terrified we were during the experience. Decades of research have shown that stress and trauma increase the differential storage of central over peripheral details.
[...] Which brings me, finally, to memory retrieval. I only have time to say a few important things.
Yes, memories generally fade. That’s partly because what starts out as a relatively detailed memory becomes more abstract over time. We remember the gist of what happened and a few of the most central details. When we remember or tell the story, our brain is literally piecing it together on the fly. That’s another reason why, as memory researchers love to say, memory is not like a videotape. Sometimes we get confused. Sometimes other people, or even movies we watch, supply inaccurate details that are inadvertently re-encoded into the overall memory and its abstract story.
But memories of highly stressful and traumatic experiences, at least their most central details, don’t tend to fade over time. And while people may have the superficial abstract stories they tell themselves and others about their worst traumas, that’s not because the worst details have been lost. It’s often because they don’t want to remember them, and don’t (yet) feel safe to remember them.
[...] for many victims of sexual assault [...] They have bland abstract descriptions they tell themselves and others, for example, their husband early in the marriage, before they feel safe enough to share the painful details, and that sharing some of those is necessary for other reasons. They might not have retrieved the horrific central details for months or years. But that doesn’t mean those vivid sensory details and wrenching emotions aren’t still there, never going away, ready to be retrieved under the right (or wrong) circumstances.
Yes, peripheral and less central details can get distorted more easily than many people realize. But decades of research have shown that the most central details are not easy to distort, which typically requires repeated leading questions from people in authority or a very strong internal motivation for doing so. But without compelling evidence of such influences, there is no scientific or rational basis for assuming that such distortions have occurred, especially for those most central and horrible details the person has been both tormented by and trying to avoid, sometimes successfully and sometimes not, for years or even decades....
MORE: https://blogs.scientificamerican.com/obs...t-victims/