Tuesday, 8 June 2010

The fallibility and malleability of memory

Arts & Letters Daily points to William Saletan's worrying piece on the work of Elizabeth Loftus. She began as the researcher pointing out the fallibility and malleability of memory, showing how eyewitness accounts were unreliable and how therapists could implant false memories of childhood abuse. But she's moved on a bit from there, now suggesting memory therapy as a way of planting false memories of childhood aversions to fatty foods as a useful way of achieving a healthy diet.

When Loftus saw the results, an idea came to her. What if you could produce similar aversions to fattening foods? Could false memories help people eat a healthier diet? She tried the experiment again, first with potato chips, then with chocolate chip cookies and strawberry ice cream. The potato-chip version failed, apparently because potato chips were too familiar as a tasty snack. But the ice-cream version worked. More than 40 percent of subjects were persuaded that they had gotten sick eating strawberry ice cream, and these subjects were significantly more likely to say they would avoid it.

In February 2005, Loftus and her coauthors published the egg study, concluding that "humans can be trained to avoid food." Four months later, they published the ice-cream study under the title, "False Beliefs About Fattening Foods Can Have Healthy Consequences." The diet-improvement rationale, originally an afterthought, was now central. The bottom line, they wrote, was that "we can, through suggestion, manipulate nutritional selection and possibly even improve health."

In the food experiments, all the threads of Loftus' career came together. Instead oftraining a rat, she was training people. Instead of using a reward, she was using the techniques she had learned from the recovered-memory therapists. And instead of planting bad memories, she was planting healthy ones. She was a real-life memory doctor.

But she, too, was responding to behavioral reinforcement. The fattening-food experiment was the most widely celebrated study she had ever done. It made headlines all over the world and earned her a place on the New York Times Magazine's list of the year's most innovative ideas. She was being rewarded for doing something socially useful. She reveled in the attention and acclaim. She quoted her press clippings in speeches.

In reality, the work she had done on memories of sexual abuse was more important. But that work had hurt and angered people. It had brought condemnation and contempt on her. In diet therapy, she found no such punishment. Again, she was meeting people who desperately needed her. But this time, they were fighting obesity, not deluded daughters. "I wish I could be of more immediate help to these people, but I'm forced to tell them that the line of research is at its very earliest stages," she wrote in 2007. "Still, it is refreshing to be working on a topic that could indeed be of genuine help to people and one that is not as anger inspiring and dangerous as the topic of sex abuse."

All those years, Loftus had been vilified for attacking therapy. Now she was inventing a therapy of her own. But hers was different. It was good for people, and she could make it better. She began to think of ways to magnify its power: ratcheting up the false feedback, perhaps, or showing photos or videos of people being sickened by the designated foods. Soon she was convincing students that they had loved asparagus as children. "Healthier Eating Could Be Just a False Memory Away," said the published journal article.

Loftus talked about the food experiments the same way she had talked about EPS. The concept, she explained, was to "tap into people's imagination and mental thoughts to influence their food choices." But two crucial elements had changed. First, she was now trying to influence behavior through memory, not just through imagination. In EPS, memory modification had been a kind of collateral damage. In the food experiments, memory modification was the whole idea.


But would freedom of choice survive therapeutic deception? Would it survive social pressure to fix unhealthy memories and habits? Loftus and her colleagues were already presenting memory therapy as an alternative to coercion. In their article on fattening food, they warned that unless behavioral scientists stemmed the obesity crisis, laws might be imposed to induce healthier eating, just as "seatbelt laws were imposed upon us when people were not using them on their own." In their article on alcohol, they offered memory doctoring as an alternative to electric shock and other "invasive" aversion therapies.
So, the next nudge then. Public service announcements that don't browbeat us about behaviours but rather try to plant false memories of childhood experiences. Remember eating asparagus with your grandma and how happy that made you when you were five? How you helped her to pick the asparagus? Weren't you happy then? And don't you remember how your father beat your mother that time he drank too much? Weren't you sad seeing that? Doesn't asparagus make you feel warm and good all over while alcohol makes you feel a little sick?

Go read the whole Saletan piece, which has excellent discussion of Chinese mass propaganda trying to implant false memories of the Tiananmen Square protesters having attacked PRA soldiers first. Didn't you remember that Greedo shot first too?


  1. I'd heard about the work on recovered memories and eyewitness testimonies, but had always assumed they were mostly cases of confused memories and substitutions rather than out and out inventions. Not that this makes them any less false or suspect for use as courtroom testimony. It is spooky to think that we can be so easily misled and influenced. Having said that, if somebody presented me with photographic "evidence" of, for example, Obama shaking Ahmadinejad's hand, without knowledge to the contrary I would assume that the meeting took place rather than it being a doctored photo. I'd like to think, however, that I wouldn't claim to remember seeing it happen. Of course if I was told one of the photos was a fake I would possibly suspect that one given the animosity between the two.

    And I applaud Han for taking out Greedo, the little slimeball couldn't be trusted anyway, he was gonna sell them out to the Empire. Long live the original cut. :)

  2. No no, Han just convinced Greedo that he had disliked organized crime as a child. Then they enjoyed some Emperor's Choice Low-Salt Ketchup.

  3. Everyday you find out how right Thomas Szasz was