Currently on display in the Tufts Art Gallery is an exhibit called "A Tapestry of Memories: The Art of Dinh Q. Lê." Lê, who was born in Vietnam, wove together strips cut from iconic photos and stills from Hollywood representations of the Vietnam War and visual representations of American pop culture to explore how his memory of the war was as much constructed by recreated narratives and his post-war experiences as it was by his actual time living through it.
The psychology department is taking a more scientific approach to the same theme. Recent research by the department explores the construction of memory from the standpoint of cognitive research. Assistant Professor Ayanna Thomas of the cognitive aging and memory lab recently published a study finding a strong link between repeated testing of the human memory and its propensity to recall false information as the truth.
Thomas's research focuses on the construction of memory, as well as the link between people's confidence in their memories and whether or not such recollections are actually true. She explained that this study was designed to explore the concept of false memory, which posits that the human mind often recalls specific events or impressions that a person did not actually experience as real memory.
"We're not going through our lives remembering exactly what has happened," she said. "Memory is reconstructed in nature."
Thomas and her team wanted to see how people's susceptibility to distorted memories was affected by repeated testing, which is viewed by psychologists as a way to help people remember things in the long term. "There [are] robust phenomena that show that when an individual receives a lot of information, they retain it better in the long term after repeated testing."
Before the experiment, Thomas hoped to find a way to guard against the formation of distorted memories. "[We thought that] we might be able to reduce people's susceptibility to memory distortion by giving them a test before they received false information," she said.
Subjects in the test viewed an episode of the popular television show "24" and were tested on the episode immediately after it ended. The subjects were then read a narrative about the television show that included false information about aspects of the episode that had been on the test. Next, subjects re-took the same test.
When Thomas compared subjects' results on this test with those of subjects who had not taken the first test, she found a surprising result.
"Subjects who took two tests were even more susceptible to false memory than those who took the standard misinformation test," Thomas said. "Instead of the initial test benefiting their memory, it impaired people's ability to remember the actual details of the event."
Thomas and her associate researchers were initially puzzled by the result, as they thought retrieval through testing would enhance memory.
Thomas has since developed the idea that the test held between the viewing of the show and the misinformed narrative actually served to focus subjects' attention on the misinformation, making them more likely to remember it.
"They seem to be basing their memories on the information that is most accessible to them," Thomas said. "Information in the narrative is highly accessible, because it was recently presented, and the subjects seem to be reacting to information in the narrative that was tested in the first test."
When subjects were warned about the possibility of misinformation, however, they were more likely to score well on the second test.
Thomas also found that subjects' bias toward the information in the narrative, drawn from its accessibility, led participants to be overconfident about the objective truth of what were, in reality, false memories.
Still, the researchers did find that subjects who took two tests and heard a factually accurate narrative reconstruction of the show scored better than those who only took one test and heard a factually accurate narrative. "The benefit of repeated testing does exist," she said, "but you have to compensate for reliance on accessibility."
In terms of broader applications of the research, Thomas maintains that patterns in memory distortion and individuals' confidence in their memories have significant applications to the legal system. "We're talking about how people can react to events that they've witnessed," she said.
She added that witnesses to high profile crimes often hear incorrect information reported by the news about the very crime they witnessed and can incorporate these false reports in their memories. "We can reduce an accessibility bias by warning subjects," she said. "If you tell people how their memory can be manipulated, that should help them if they are young, healthy individuals."
Thomas explained that humans are frequently being asked to recount previous events and learned information, but constantly experience new things. "Students in classes, witnesses to crimes … there is a strange conflict between what is required of us and what we can actually do," she said.
Thomas is currently working to further explore the phenomenon of confidence and how testing on a piece of information causes people to attend to that information when it is repeated to them. The broad takeaway from her research, however, is already apparent.
"It is so easy to distort memory," Thomas said.
