Last July, in "Remembering Something That Never Happened," I reported on some basic brain research that helps us understand how new, seemingly accurate—but completely false—memories can form in the brain. Now a new piece of research reported in this week's Proceedings of the National Academy of Sciences adds to our understanding of that complex and deceptive phenomenon.
Lawrence Patihis and colleagues at the University of California, Irvine, report that even people with extraordinary memories are vulnerable to memory distortions. The research team compared susceptibility to false memories among 38 people with typical memories and 20 people identified as uniquely gifted in their ability to accurately remember even trivial details from their distant past. Called Highly Superior Autobiographical Memory (HSAM), this ability, previous research shows, enables certain people to remember details of events from every day of their life since mid-childhood, including the day of the week any date fell on.
The researchers used a number of established techniques for measuring memory distortion. They found that
• HSAM participants and controls were both susceptible to false recognition of nonpresented words in a wordlist.
• HSAM participants were equally as likely as controls to mistakenly report that they had seen nonexistent footage of a plane crash.
• HSAM participants showed higher overall false memory compared with that of controls for details in a photographic slideshow.
Patihis says he got the idea for the study when he watched a 60 Minutes report on HSAM in December, 2010. He wondered immediately if people who possessed such extraordinary memory would be vulnerable to memory distortion like all the rest of us. "The message that memory could be almost perfect worried me, and I wondered if eventually that would trickle down into areas like clinical psychology and the legal system," says Patihis.
The study's findings refute the idea of perfect memory in anyone. "It is important to note that HSAM individuals do truly have exceptional memory, and our study does not contradict this. It is only when we introduce misleading information do they show similar levels of distortion to ordinary memory people, [at least] some of the time," Patihis adds.
Patihis thinks that susceptibility to memory distortions is a fundamental part of having a human brain. "But it is not just this study that makes me think like that. On other measures such as personality and intelligence, we have found that vulnerability to memory distortions is present in those … of all personalities and intellects," he says. Patihis suggests that his best practical advice is to assume that everyone is susceptible to memory distortions from time to time—a principle that is critical in the practice of psychology, in law enforcement, and in the justice system, where memory evidence can tear families apart or lead to prison sentences.
"What I love about the study is how it communicates something that memory distortion researchers have suspected for some time, in a vivid way--that perhaps no one is immune to memory distortion." Patihis says. "In the past I have worried that the general public has heard that [for example] 25 percent of participants in a study developed false memories, and then thought, 'It might happen to them, but it won't happen to me.' This study will probably make some nonexperts realize, finally, that if even memory prodigies are also susceptible, then they probably are, too.
"This is this teachable moment that is almost as important as the scientific merit of the study. The study could help in educating people, including professionals who deal with memory evidence (such as clinical psychologists and legal professionals) about false memories because it is relatively easy to understand, interesting, and a vivid demonstration."
For More Information
Lawrence Patihis et al. False memories in highly superior autobiographical memory individuals. PNAS Online Early Edition, November 18, 2013.
Lawrence Patihis is an NSF Graduate Fellow in Social and Behavioral Sciences at the University of California, Irvine.