How the neurobiology of trauma affects rape accusations

When Jackie, the woman at the center of a recent Rolling Stone article about sexual assault at the University of Virginia, gave conflicting details about her alleged gang-rape by seven fraternity brothers, news outlets were quick to suggest that she may not have been telling the truth.

But psychologists say inconsistencies in survivors’ accounts of violent trauma are common. Recent neurobiology research suggests that when a person is experiencing a traumatic event, “fight or flight” hormones and neurotransmitters flood the body, affecting the way the brain encodes memories — so much so that they tend to be disjointed and out of chronological order.

Researchers say the traumatized brain can go into survival mode, capturing vivid sensory details of a life-threatening event — what a weapon looked like in a shooting, for example, or how a room smelled — while completely skipping over or scrambling details such as time or location.

Rebecca Campbell, a psychology professor at Michigan State University whose research focuses on sexual assault and violence against women, compares the experience of the brain recording its memory of an assault to taking lecture notes on tiny Post-its rather than on a full sheet of paper.

“All those Post-it notes get scattered all over the world’s messiest desk,” she said. “The telling is going to be fragmented. It’s going to be disorganized, because that’s the way the memory is laid down in the brain. It’s an imperfect capture.”

The brain can retain memories in this faulty way during any type of traumatic event, whether it’s a soldier in combat, a police officer in a shooting or a driver in a car accident, Campbell said. And if the person develops post-traumatic stress disorder as a result of the trauma, his or her memory of the incident is likely to be even more affected. 

Campbell travels the country training law enforcement officers, prosecutors, the military, college campus staff and advocates for sexual assault survivors about this research on memory and trauma. Her goal is to raise awareness among those who respond to reports of sexual assault that survivors' memories may be jumbled and that inconsistent details may not necessarily indicate a false accusation.

That, in turn, may increase the rate at which reported rapes are prosecuted. According to the National Alliance to End Sexual Violence, only 5 to 20 percent of rapes are reported to authorities, and only 0.4 to 5.4 percent of them are prosecuted.

The research done by Campbell and others throws the controversy over the Rolling Stone report into a new light. The Washington Post interviewed Jackie and several of her friends, and reported that details in her account changed over time. Rolling Stone initially blamed Jackie for the inconsistencies but then took responsibility for failing to contact the accused. That sparked a firestorm of criticism over whether the public would become more reluctant to believe similar accounts by sexual assault survivors. 

“After this I can't imagine a survivor being willing to come forward about their assault at all,” Dana Bolger, co-founder of the anti-sexual assault student activist group Know Your IX, said in an email. “And as a result of Rolling Stone's mistakes, the American public will spend more time picking apart Jackie's story than demanding change from the system that failed her and so many others."

David Lisak, a clinical psychologist who studies the causes and consequences of sexual assault among men and women, finds another lesson in the controversy over Jackie’s story: It is a mistake to assume that any inconsistency in a report of trauma is a sign of a false report.

It is completely normal, he said, for hormones and neurotransmitters released during a traumatic event to muddle a person’s memories.

“You could almost say it is routine for somebody who has had this kind of traumatic experience to not remember particular things, to remember different things at different times, and also to get certain things wrong,” he said. “That stems directly from how the brain is affected by those intensely terrifying experiences.”

While the public may focus on high-profile reports of false allegations, such as the woman who accused Duke lacrosse players of gang rape in 2006, those cases are rare. Lisak co-authored a 2010 study analyzing 136 cases of sexual assault (PDF) that took place at a northeastern university over 10 years. When he defined "false" in a consistent way (meaning there was enough evidence to prove an assault didn't occur, or the victim later admitted he or she had made it up), Lisak found that "false" allegations occurred in only 5.9 percent of the reported cases.

In looking at past studies of false reports, which used different definitions, Lisak used the consistent standards to determine that, on average, there were false accusations in only 2 to 10 percent of the incidents reviewed (PDF).

Lisak, Campbell and others, including Sen. Claire McCaskill, D-Mo., who is looking into legislation to address sexual assault on college campuses, say there are techniques that law enforcement officials can use to compensate for the way the traumatized brain records violent events. For example, investigators can allow victims to share recollections of what happened without asking for them in chronological order.

"What you want to stay away from at all possible is, 'Tell me what happened and start from the beginning,'" Lisak said. "That’s a question that is essentially expecting that this person has a normally functioning hippocampus [a portion of the brain dealing with memory] and recalls what happened in that sort of normal way, when it is quite possible that they don’t."