Foreign Language Reduces False Memories by Increasing Memory Monitoring

People have false memories that distort their recollection of past events. Language is an important source of such memories, from providing false inferences to outright misinformation. Here we investigate the impact of using a native or foreign language on bilinguals' susceptibility to false memories. Although language has been argued to impact false memories in multiple ways, our study was inspired by recent work in the decision-making literature, which leads to the novel hypothesis that foreign language encourages people to engage in careful memory monitoring that could reduce false memories. This hypothesis contrasts with a processing load account, which predicts that a foreign language would increase false memories because it is naturally more difficult to process information in a foreign language. We tested these hypotheses using two false memory tasks. Using the DRM task, Experiment 1 found that individuals were more accurate in identifying false memories when using their foreign language compared with their native tongue, consistent with the memory monitoring hypothesis. Using the misinformation task, Experiment 2 found that processing misleading information in one's foreign language eliminated false memories, again supporting the hypothesis that a foreign language increases the use of memory monitoring. These findings support a monitoring hypothesis that has been overlooked in prior studies on bilingualism and false memory, with implications for billions of people who regularly use a foreign language.