Jessica Payne had seen and read much about false memories. In particular, she had read about witnesses to violent crimes who misidentified the perpetrators. But as a graduate student of neuroscience at the University of Arizona, she was shocked to discover that there was almost no research on the effect of stress in creating such memories. Payne decided to study the phenomenon herself, and her research strongly suggests that stress can alter memories by messing with the way they are consolidated.

To conduct the study, Payne began with a standard stress experiment: She told 40 people to deliver a speech in front of what they thought was a panel of judges behind a one-way mirror. She gave them 10 minutes to prepare the speech and then, just before they were about to speak, she took away their notes. Next, the stressed-out subjects listened to a list of words and were later asked to recognize them. Payne then compared their answers with those collected from 40 unstressed people.

The stressed group was more likely to falsely remember lists
of related words. For instance,
if the list included words like candy, sour, sugar, and chocolate, stressed people were more likely to “remember” that words like sweet were also on the list.

“These results really speak to the issue of eyewitness testimony,” Payne says. “Witnessing a crime is so stressful, it may be very difficult for a witness to pick out the right person from a lineup.”