Can You Tell a False Memory From a True One?

New Scientist
Stories from New Scientist.
Sept. 8 2013 9:30 AM

I Could Have Sworn …

An interview with false-memory expert Elizabeth Loftus.

(Continued from Page 1)

AG: What is the current focus of your research?
EL: In 2003 I was sued after I published an exposé of a woman's case that hinged on "repressed" memories, even though I had not named her. Once that was over, I started to focus on the repercussions of the types of false memories we all have. Once they take hold, do they have consequences down the road? One way to look at that was to plant a false memory that might change your behavior—for example, that you got sick eating a particular food.

AG: How do you plant these memories?
EL: We use a "false feedback" technique. We gather a whole bunch of data from you, about your personality, thoughts about different foods, all kinds of things. Later, we hand you this computerized profile, which reveals certain things that probably happened when you were a child. In the middle of the list is, say, that you got sick eating strawberry ice cream. We give you false feedback about your data, and then encourage you to elaborate and imagine.

Later we ascertain whether you have a belief that it happened to you. Then we offer you a choice from all these different foods. In that example we found that participants didn't want strawberry ice cream as much.

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Later studies have shown that if you plant a false memory about a certain food, when you offer people that food, they don't eat as much of it.

AG: This works with alcohol too?
EL: Yes. We did a similar kind of false-feedback study with vodka. If we make people believe that before the age of 16 they got sick drinking vodka, they don't want to drink as much vodka.

AG: Could false memories be used for therapeutic purposes—like reducing alcohol consumption?
EL: Absolutely, yes. I've had people say to me, do you think you could cure all kinds of problems with the false-memory technique? I hope other people will give it a try.

AG: Isn't the deliberate planting of false memories entering into ethically dubious territory?
EL: Therapists probably can't ethically do it, and they may have anti-deception provisions in their standards of conduct. But bad governments, bad people, they don't have requirements of conduct. When we recently published a study about planting false memories among U.S. soldiers, I was worried we were putting out a recipe for how you can do horrible things to somebody and then wipe their memory away.

AG: How did you conduct this study of U.S. soldiers?
EL: A psychiatrist named Charles Morgan has been studying soldiers going through survival school, where they learn what it would be like if they were ever captured as prisoners of war. I had a chance to work with him, and we introduced misinformation to see if we could get these trained soldiers to misidentify their interrogator. Even with a traumatic event, highly trained soldiers can be misled too.

AG: Is there any way to distinguish a false memory from a real one?
EL: Without independent corroboration, little can be done to tell a false memory from a true one.

AG: Could brain imaging one day be used to do this?
EL: I collaborated on a brain imaging study in 2010, and the overwhelming conclusion we reached is that the neural patterns were very similar for true and false memories. We are a long way away from being able to look at somebody's brain activity and reliably classify an authentic memory versus one that arose through some other process.

AG: Do you think it's important for people to realize how malleable their memory is?
EL: My work has made me tolerant of memory mistakes by family and friends. You don't have to call them lies. I think we could be generous and say maybe this is a false memory.

This article originally appeared in New Scientist.

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