If adults claim to have suddenly remembered painful events from their childhood, are those memories likely true? This question is the basis of the “wars of memory” that have been upsetting psychology for decades. And the validity of buried trauma becomes a point of contention in court cases, as well as in television and film stories.
Warnings about the reliability of a forgotten traumatic event to be remembered later – formally known as delayed memory – have been endorsed by leading mental health organizations such as the American Psychiatric Association (APA). The skepticism is based on a series of research showing that memory is unreliable and that simple manipulations in the laboratory can lead people to believe that they have had an experience that never happened. Some prominent cases of restored memory of child abuse have been found to be false and provoked by overzealous therapists.
However, psychotherapists who specialize in treating adult survivors of childhood trauma argue that laboratory experiments do not rule out the fact that some delayed memories that adults remember are factual. Trauma therapists claim that abuse experienced early on can overwhelm the central nervous system and cause children to cleave painful memories from consciousness. They claim that this psychological defense mechanism – known as dissociative amnesia – occurs routinely in the patients they encounter.
Tension between the two positions has often been portrayed as a debate between hard-core scientists on the false memory side and therapists in clinical practice in the lagged memory camp. Research clinicians have been publishing peer-reviewed studies on dissociative amnesia in leading journals for decades. A study published in February in the American Journal of Psychiatry, The APA’s flagship highlights the considerable scientific evidence supporting the trauma therapists’ arguments.
The new paper uses magnetic resonance imaging (MRI) to examine amnesia, as well as various other dissociative experiences that are said to often occur after severe child abuse, such as: B. Feelings of unreality and depersonalization. In an editorial published in the same issue of the journal, Vinod Menon, professor of psychiatry and behavioral science at Stanford University School of Medicine, praised the researchers for “[uncovering] One possible mechanism of brain circulation underlying individual differences in dissociative symptoms in adults with early trauma and PTSD [post-traumatic stress disorder]. ”
Milissa Kaufman is lead author of the new MRI study and director of the dissociative disorder and trauma research program at McLean Hospital, a teaching hospital at Harvard Medical School. She notes that, as with previous MRI studies of trauma survivors, this shows that there is a neurological basis for dissociative symptoms such as amnesia. “We believe these brain studies can help reduce the stigma associated with our work,” says Kaufman. “Like many therapists treating adult survivors of severe child abuse, I have seen some patients regain memories of abuse.”
Dissociative amnesia has been in every edition of the Diagnostic and Statistical Manual of Mental Disorders ((DSM) – the diagnostic bible of psychiatry. The disease was supported not only by psychiatric case studies, but also by dozens of studies involving victims of child abuse, natural disasters, torture, rape, kidnapping, war violence, and other trauma.
For example, psychiatrist James Chu, then director of the trauma and dissociative disorder program at McLean Hospital, published a study two decades ago of dozens of women who were hospitalized and had experienced child abuse. A majority of women reported having previously had partial or total amnesia of these events, which they would normally not remember during a therapy session but at home alone or with family or friends. In many cases, Chu wrote, these women have “found strong confirmation of their restored memories.”
False memory advocates have warned that investigators’ use of guiding questions could provoke an untrue memory. As psychiatrist Michael I. Goode wrote about Chu’s study in a letter to the editor: “Participants were asked if there was any period of time when they did not remember it [traumatic] Experience happened. “With this question alone, the timeliness of the traumatic experience was naturally confirmed by the investigators.”
MRI studies over the past two decades have shown that PTSD patients with dissociative amnesia have decreased activity in the amygdala – a region of the brain that controls the processing of emotions – and increased activity in the prefrontal cortex that controls the planning, the Focus and other executive functions controls competencies. In contrast, PTSD patients who do not report loss of their trauma memories show increased activity in the amygdala and decreased activity in the prefrontal cortex.
“The reason for these differences in neural circuitry is that PTSD patients with dissociative symptoms such as amnesia and depersonalization – a group that comprises between 15 and 30 percent of all PTSD patients – switch off emotionally in response to trauma,” says Ruth Lanius, a professor of psychiatry and director of the PTSD research unit at the University of Western Ontario, who has conducted several of these MRI studies. Children could try to break away from abuse to avoid excruciating emotional pain that could cause them to forget an experience for years to come, she claims. “Dissociation involves psychological escape when physical escape is not possible,” adds Lanius.
False memory researchers remain skeptical of brain imaging studies. Henry Otgaar, Professor of Forensic Psychology at the University of Maastricht in the Netherlands, who has co-authored more than 100 scientific publications on false memory research and often acts as an expert witness for defendants in cases of abuse, claims that intact autobiographical memories are seldom – if ever – suppressed. “These brain studies only provide biological evidence for that Expectations of patients who report memory loss due to dissociation, ”he says. “There are many alternative explanations for these correlations – for example, retrograde amnesia, where forgetting is due to a brain injury.”
To strengthen their arguments, Kaufman and her McLean colleagues used artificial intelligence to model the connections between different brain networks that could explain dissociative symptoms. They fed the computerized MRI data of 65 women with a history of child abuse who had been diagnosed with PTSD and their findings using a commonly used inventory of dissociative symptoms. “The computer did the rest,” says Kaufman.
Their main finding is that severe dissociative symptoms likely affect the connections between two specific brain networks that are active at the same time: the so-called standard mode network – which kicks in when the mind is at rest and is remembering the past and imagining the future – and the frontoparietal control network – which is involved in problem solving.
The McLean study is not the first attempt to apply machine learning to dissociative symptoms. In one in the September 2019 issue of British Journal of Psychiatry, The researchers showed how MRI scans of the brain structures of 75 women – 32 with dissociative identity disorder for whom dissociative amnesia is a key symptom, and 43 matched controls – can distinguish between people with and without the disorder nearly 75 percent of the time.
Kaufman says additional research needs to be done before clinicians can begin using brain connectivity as a diagnostic tool to assess the severity of dissociative symptoms in their patients. “This study is just a first step towards precision medicine in our field,” she says.
Richard Friedman, professor of clinical psychiatry at Weill Cornell Medical College, believes the McLean researchers’ goal is commendable. He notes, however, that the road ahead remains challenging and warns that the history of psychology is filled with “objective assessments” for a particular diagnosis or state of mind that never lived up to its hype. Friedman cites the case of polygraph tests, which have many false positives and false negatives.
While a brain-based test that could diagnose dissociative symptoms isn’t likely anytime soon, research into neurobiological explanations shows that the controversy over forgetting and remembering traumatic memories is far from resolved.