Mar 26, 2021

False Memories Can Be Planted and Then Reversed, Researchers Find

German study points to possible techniques for recognizing and correcting erroneous recollections

The new study confirms previous research on the malleability of memory. Some earlier findings suggest true memories tend to be stronger than false ones.
The new study confirms previous research on the malleability of memory. Some earlier findings suggest true memories tend to be stronger than false ones.

Brianna Abbott
March 22, 2021

Researchers in Germany and the U.K. said they were able to plant false memories and then help study volunteers root them out, work that suggests potential remedies to ease the problem of erroneous recollections.

The scientists used interviews to convince some study subjects they had undergone childhood events that didn’t happen to them, such as getting lost or being in a car accident, according to a report published Monday in the scientific journal Proceedings of the National Academy of Sciences.

Then the researchers said they used other interview techniques that prompted the volunteers to reassess the memories and help realize they might be false or misremembered.

The work confirms previous research on the malleability of memories while pointing to potential techniques for recognizing and rooting them out.

“What we can show in principle is that it’s possible to empower people to really identify what might be a false memory,” said Aileen Oeberst, the study’s lead author who now heads the Department of Media Psychology at the University of Hagen in Germany.

Scientists have long studied the fallibility of human memory. The findings confirm previous research, psychologists and cognitive scientists said, though they cautioned about its real-world potential since the study was conducted among a relatively small number of subjects in a lab over a few weeks, and its findings might be hard to apply to an individual person.

Some research suggests that true memories tend to be stronger for people than false ones, Nancy Dennis, a memory researcher and an associate professor of psychology at Pennsylvania State University. Yet people can also have vivid false memories or weaker true memories, making them difficult to tease apart on an individual basis.

“The hard part is when you want to take someone on that witness stand or therapists’ office and want to figure out if that particular memory is true or false,” said Dr. Dennis, who wasn’t involved in the study.

False-memory research has been controversial. Cognitive scientists and psychologists often disagree on how easy it is to develop false memories and how often that occurs. It has also been controversial partly because police investigations and court proceedings rely on the quality of memories.

Some psychologists express concerns that people can be cajoled into confessing crimes they didn’t commit or into making incorrect accusations. Meantime, others say the bigger problem is that defendants often point to false memory research to discredit testimony from real victims or eyewitnesses and get allegations dismissed.

In the new study, researchers sought to prove what they said was a relatively unexplored area of research: how to undo false memories.

The study involved 52 people, averaging 22 years of age, at the Johannes Gutenberg University of Mainz, Germany, who were told they were enrolling in research on childhood memories, as well as their parents. Researchers asked both the subjects and their parents not to talk with each other about the study.

The study had two parts. In the first part, the researchers sought to plant false memories in the subjects. First, researchers sent a questionnaire to the parents of volunteers, asking them whether their child had undergone negative experiences like getting stung by a wasp or running away from home.

The investigators also asked the parents to suggest two events that definitely didn’t happen but could have taken place, as research suggests that false memories are more likely to be picked up if they are plausible to that person.

Interviewers spoke with study subjects over the course of three interviews to plant false memories. The interviewers didn’t know whether or not a recollection was real, and they weren’t aware they were being used to plant false memories.

In their conversations, the interviewers told the subjects that their parents had provided details about events in their childhoods. Then the interviewers introduced four “memories” that the interviewers said the parents had told them about—two real and two fabricated.

The interviewers pushed the participants to recall the events to varying degrees. For one true and one false event, the interviewers only lightly suggested that the event occurred over the course of three interviews. For the other two incidents, the interviewers pushed the subjects to recall the events and encouraged the subjects to think about the incidents between interviews.

Volunteers faced both more aggressive and less aggressive interview styles. At the end of the three interviews, volunteers said that they had some level of memory about the fake events 27% of the time after the interviewers mildly suggested an event. When interviewers were more aggressive, participants subscribed to the made-up events 56% of the time, the study said.

Volunteers described full or robust memories for 20% of the minimally suggested events and just under 45% of those aggressively suggested. Some people still outright rejected the fake events or said they had no memory of them.

In the second part of the study, researchers tried to see whether they could reverse the false memories over two additional interviews.

First, one interviewer told the volunteers that memories might not be based on their own experiences but rather on sources such as family stories or photographs, and they asked for the origin of each recollection. Then during a second session, a new interviewer said that repeatedly being asked to remember events could lead to the creation of false memories and asked the volunteers to think back and reflect on whether that applied to any of the incidents.

After those interviews, fewer study subjects subscribed to the fake memories, though a few people still described the false memories in detail, the study found.

Overall, volunteers had more confidence in their true memories and described them in fuller detail than the memories that were false, the study found. And while belief in the fake incidents decreased after the final two interviews, faith in the real memories remained relatively intact.

Write to Brianna Abbott at

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