The study included 23 young adults with no history of mental impairment. Participants were shown 24 sets of 12 slides. Each set of slides portrayed different geometric shapes, which varied in number, size, position, shape and color.
After studying each group of slides, the participants were shown an additional five slides and asked if they had seen any of the shapes on these additional slides in the original set.
For example, participants were shown a set of 12 slides each showing yellow triangles. Each slide showed one, two or three large or small triangles; multiple triangles were arranged either vertically or horizontally. In this case, the lure slide part of the five additional test slides showed two small yellow triangles lined up horizontally below a large yellow triangle. But while it looked similar to slides in the original group, it wasn't part of the initial set.
Participants accurately identified the images they had seen in the original set 80 percent of the time. They also correctly identified the images that obviously weren't part of the original set of shapes more than 98 percent of the time. But they incorrectly said they had seen the lure images 60 percent of the time.
"False memories can be created using visual stimuli with minimal language input," Beversdorf said. "The question now is whether this can be done entirely without the use of semantics."
Beversdorf plans to apply these findings and this research model to future studies on autistic people.
In previous work, Beversdorf found that some people with autism spectrum disorder (ASD) performed better on a "false-memory" test than did normal control subjects. People with ASD have an impaired ability to use context, and, in a prior study, that inability improved the ASD subjects' ability to discriminate between words that had and had not been on a word list.