Once You Start Trusting a Source, Beware the Trust Trap
Posted Oct 05 2009 10:02pm
If you follow a news commentator closely, reading everything he or she writes in whatever venue it appears, you may unknowingly be in a trust trap. Studies have shown that once we invest trust in a particular source of knowledge, we’re less likely to scrutinize information from that source in the future.
Now a new study in the journal Applied Psychological Science has taken this investigation a step further, showing that the trust trap can also result in the creation of false memories — and not only in the short term.
Researchers crafted an experimental design in which they exposed two groups of participants to a series of images followed by narration about the images. The first group (refered to as the “treat-trick” group) received mostly accurate narration about the images. The comparison group received mostly misinformation. Both groups then completed tests of recall to determine how much accurate versus inaccurate information they remembered.
One month later, the participants were brought back to undergo the same experiment, except this time the treat-trick group was given misinformation during the narration (ie. the “trick”), as was the comparison group. Both groups again completed tests of recall.
Here’s what happened: In the first session, the treat-trick group had a significantly higher rate of true memory versus the comparison group (which we’d expect since only the comparison group was given misinformation during this session) — at a rate of about 82% for the treat-trick group and 57% for the comparison group.
But in the second session, in which both groups were given misinformation one month later, the treat-trick group had significantly lower true memory recall than the comparison group: 47% versus 58%. The graph below shows overall results for both sessions of the study.
The most likely reason for this effect is that the treat-trick group fell into a trust trap. Because information provided by the narrative source in the first session was accurate (and test scores were high as a result), participants believed the source to be credible and trustworthy. The comparison group, on the other hand, had no reason to invest trust in the original source and exhibited recall at roughly the same level for both sessions.
What’s most interesting is the timeframe of this effect. Researchers conducted the sessions a month apart, allowing ample time for a trust effect to wear off. But it didn’t.
The real-world implications of this research are important. Eyewitness testimony can be changed when a witness listens to an information source they’ve previously trusted as credible (either media, interrogators, or other people), and this study suggests that the window of opportunity for this effect is large. Any follow-up information received by an eyewitness from any number of sources can significantly alter his or her memory.
Yet another example of how malleable our memories truly are, and the risks we run of putting so much faith in something so changeable.
Zhu, B., Chen, C., F. Loftus, E., Lin, C., & Dong, Q. (2009). Treat and trick: A new way to increase false memory Applied Cognitive Psychology DOI: 10.1002/acp.1637