The Science of Memory



A darkly lit photo of a police/law enforcement evidence room shows an evidence board with pinned photos, sticky notes, and more. A laptop and task lamp, both off, sit atop a desk below the bulletin board. Also on top of the desk are various files, papers, and a large binder. The photo accompanies a blog post about the science of memory, its relationship to personality, and the reliability of memory recall (both in the workplace and in criminal investigations using eyewitness testimony).

Personality can affect our memory, which is not as reliable as we’d like to believe.

Recently on The Science of Personality, cohosts Ryne Sherman, PhD, and Blake Loepp spoke with Ryan Rush, PhD, a consultant on the corporate solutions team at Hogan Assessments, about the science of memory.

A former professor of psychology, Ryan has conducted research on the social nature of memory, including false memories and the effect of emotion on memory.

“We cherish our memories. They make us who we are. It’s often hard for us to accept that they’re not always accurate,” Ryan said.

Keep reading to learn more about memory and personality, memory recall, and eyewitness memory.

Memory and Personality

Specific personality characteristics are likely to influence how we perceive the world. In turn, this influences what information we notice and how we encode that information in our memories. When we recall a memory, personality can also affect how we perceive the information.

Ryan used the Hogan Personality Inventory’s Adjustment scale as an example. This scale measures the degree to which a person appears calm and self-accepting or self-critical and tense. Someone with a high Adjustment score might tend to ignore critical feedback but remember positive feedback. In such situations, they might hear all the feedback but encode only the more positive feedback into memory. Another possibility is that they hear and encode all the feedback but shape it more positively during recall.

Conversely, someone with a low Adjustment score might hear moderately critical feedback as highly critical in the moment. Upon recall, they might focus on the critical feedback but ignore the more positive feedback.

Personality also can affect how likely someone is to claim to have a good memory. Most people who would say, “I have a good memory,” probably don’t have extraordinary memory abilities. What they probably do have is confidence in their ability to recall information. Having good capabilities in short-term retention is likely part of their identity, the narrative they have created about themselves.

Memory Recall: The Social Contagion of Memory

The social contagion of memory is the idea that memory can act like a virus. “The details that we share with one person can infect another person’s memory or contaminate it with incorrect details,” Ryan explained. Errors can be transferred into someone else’s memory. “Additionally, we sometimes get correct information from others,” he added. Both errors and accuracy can be transmitted across people’s memories.

An experiment of Ryan’s involved details in photos of everyday scenes, such as a kitchen or an office. The photos contained both stereotypical and unusual items for each setting, such as a lamp and a spatula together in a living room. Two people viewed the photos separately, had a conversation about what they recalled, and then recalled the photos again individually.

“We found that if you start out with a more accurate memory before you collaborate with someone, you are likely to spread that accurate information to your partner,” Ryan said. “If you start out as less accurate, you are likely to spread some incorrect details to your partner.”

This goes beyond merely regressing to the mean. It suggests that when you’re recalling details of a meeting or studying for an exam, you can improve your memory by recalling correct details with others. If false memories can contaminate good memories, accurate memories can also contaminate inaccurate ones.

“Be careful who you recall with,” Ryan quipped.

Memory Recall: Eyewitness Identification

The social contagion of memory has significant application in eyewitness accounts of crimes. Two witnesses who see the same crime might discuss their memories of details, and these memories can contaminate each other. Suppose Witness A saw a suspect wearing a blue baseball cap. If Witness B does not initially remember any headgear but also recalls a blue cap after talking with Witness A, is that detail an error?

Eyewitness identification in real life isn’t how it’s depicted on screen. One thing that television dramas get wrong is that lineups aren’t usually conducted live behind two-way glass. They are typically photographs on paper or a screen.

Another dramatization is the pace at which witness interviews take place. Instead of solving crimes within 24 hours, investigators might question a witness days or weeks after the event. The longer the interval between the crime and the lineup, the less detailed a witness’s memory is likely to be. The memory may even become less accurate, especially if it has met inaccurate information in the meantime.

How do we make a judgment about somebody else’s recollection? “Without corroborative evidence, it is basically impossible,” Ryan said.

Wrongful Convictions

Wrongful convictions happen for many different reasons, but eyewitness misidentification is the leading cause. The Innocence Project states that 69% of DNA exonerations involve a mistaken eyewitness. Many different variables influence eyewitness memory, including stress and exposure duration (how long the witness saw the suspect). Variables of this type, called estimator variables, are outside of anyone’s control.

In researching eyewitness memory, psychologists use two types of lineups: target present and target absent. A target-present lineup has a picture of the perpetrator in it. A target-absent lineup has a picture of an innocent suspect who resembles the perpetrator.

When memory conditions are worse, witnesses are worse at identifying perpetrators in a target-present lineup. However, they remain the same at identifying the innocent suspect. While they’re less likely to identify a guilty person, fortunately they aren’t more likely to provide false identification.

Identifications of an innocent suspect do increase when system variables are poor. System variables include lineup composition, police procedures, and administrator knowledge of the suspect. Whether consciously or not, a lineup administrator who asks, “Would you like to look at this photo again?” while using certain nonverbal signals might contaminate the eyewitness’s memory. In real investigations, of course, all lineups have a genuine suspect and are conducted with unbiased administrators.

Reducing the Risk of Inaccurate Memories

“Memory is not perfect by any means,” said Ryan, “but if we can identify the best practices when it comes to those police procedures or how to conduct those lineups, we can minimize the risk as much as possible.”

Implementing an intentional process to minimize memory errors is beneficial in the workplace too. If all three people in a meeting remember the outcome differently, the inaccuracy could cause serious organizational repercussions. Taking thorough notes or using recordings by agreement can help provide the corroborative evidence for what was decided and why.

Ryan said that memory research is important, especially when someone’s memory is evidence in a trial. “Witnesses don’t always get it wrong, but when that is the only piece of evidence, you have to be careful,” he said.

Listen to this conversation in full on episode 84 of The Science of Personality. Never miss an episode by following us anywhere you get podcasts. Cheers, everybody!

Reference

  1. How Eyewitness Misidentification Can Send Innocent People to Prison. (2020, April 15). Innocence Project. https://innocenceproject.org/news/how-eyewitness-misidentification-can-send-innocent-people-to-prison/