Social pressure can implant false memories

Study reveals a unique pattern of brain activity when false memories are formed – one that hints at a surprising connection between our social selves and memory.

People sitting in cafe 311 (photo credit: Courtesy)
People sitting in cafe 311
(photo credit: Courtesy)
Many believe that if they remember something, it actually happened.
Yet a growing number of researchers are not so sure, and believe that people can by themselves, or under the influence of others, actually falsify memories. New research at the Weizmann Institute of Science in Rehovot shows that a bit of social pressure may be all that is needed. The study, which appeared recently in Science, reveals a unique pattern of brain activity when false memories are formed – one that hints at a surprising connection between our social selves and memory.
The experiment, conducted by Prof. Yadin Dudai and research student Micah Edelson of the institute’s neurobiology department with Prof. Raymond Dolan and Dr. Tali Sharot of University College London, was performed in four stages. In the first, volunteers watched a documentary film in small groups. Three days later, they returned to the lab separately to take a memory test, answering questions about the film and how confident they were in their answers. They were later invited back to the lab to retake the test while being scanned in a functional MRI (fMRI) that revealed their brain activity. This time, the subjects were also given a “lifeline”: the supposed answers of the others in their film viewing group (along with social-media-style photos).
Planted among these were false answers to questions the volunteers had previously answered correctly and confidently. The participants conformed to the group on these “planted” responses, giving incorrect answers nearly 70 percent of the time. But were they simply conforming to perceived social demands or had their memory of the film actually undergone a change? To find out, the researchers invited the subjects back to the lab to take the memory test once again, telling them that the answers they had previously been fed were not those of their fellow film watchers, but were random computer generations.
Some of the responses reverted back to the original, correct ones, but close to half remained erroneous, implying that the subjects were relying on false memories implanted in the earlier session.
An analysis of the fMRI data showed differences in brain activity between the persistent false memories and the temporary errors of social compliance. The most outstanding feature of the false memories was a strong co-activation and connectivity between two brain areas called the hippocampus and the amygdala. The hippocampus is known to play a role in the formation of long-term memory, while the amygdala, sometimes known as the emotion center of the brain, plays a role in social interaction. The scientists think the amygdala may act as a gateway connecting the social and memory processing parts of our brain; its “stamp” may be needed for some types of memories, giving them approval to be uploaded to the memory banks. Thus social reinforcement could act on the amygdala to persuade our brains to replace a strong true memory with a false one.
People suffering from the lung disease emphysema have frequent shortness of breath and feel as if they are drowning every day. In this condition, the tissues necessary to support the physical shape and function of the lungs are destroyed.
This type of chronic obstructive pulmonary disease is usually the result of smoking or long-term exposure to air pollution, and results in much suffering and death.
Usually, medications and rehabilitation techniques were used to try to relieve symptoms. Then, doctors tried surgery to remove damaged parts of the lungs to reduce the volume, but it helped only minimally. Now Sheba Medical Center at Tel Hashomer has treated four emphysema patients with help from Boston pulmonologist Dr. Edwardo Ingenito, using a non-surgical technique that seems promising.
Dr. Tiberiu Shulimzon of the pulmonology department tried biological glue to eliminate damaged tissue and fuse the rest. Working with Dr. Yael Raphaeli, he conducted preliminary studies and then developed the technique. The material and the technique are now approved for clinical use in Europe and Israel. But emphysema remains a very difficult condition, thus healthy people had best prevent it by not smoking and by protecting themselves from pollution.
Every year, as many as 6,000 Israelis need to have their thyroid glands removed due to a tumor or hyperactive functioning. In conventional surgery, a cut six to eight centimeters long is made in the neck, leaving a long and ugly scar.
Patients are hospitalized, require treatment for pain and face the risk of infection. Now patients have a choice of a new technique at Carmel Medical Center in Haifa. Called MIVT, the technique allows them to have the operation, rest a few hours and then go home.
Prof. Eitan Shiloni, director of the surgery B department, makes a small incision only about a centimeter long at the base of the neck. Using a miniature advanced video camera, he sees the suspected tissues on a screen and cuts them out using keyhole surgery, closing the blood vessels with lasers. Shiloni says patients do not need powerful drugs to treat pain, and due to the small cut, no scars are left. Shiloni invited Prof. Piero Miccoli, a senior surgeon from the University of Pisa in Italy, to demonstrate the technique before senior surgeons from Carmel and other local hospitals. Miccoli, considered one of the world’s leading neck surgeons, impressed the Israelis with his technique.
“I hope that using the new technique, we will ease the suffering of patients and make it possible for them to return to their daily routines almost without pain,” said Shiloni, who had ordered special equipment for Carmel to perform it.