False recalls, but not false recognitions, at the DRM paradigm are increased in subjects reporting insomnia symptoms: An online study.

BACKGROUND: In insomnia, poor sleep is accompanied by several cognitive impairments affecting prefrontal functioning that could affect source-monitoring processes and contribute to false memories production. By using a modified version of the Deese-Roediger-McDermott paradigm (DRM), we previously found that individuals suffering from insomnia produced more false memories than good sleepers adopting a free-recall task, especially for sleep-related stimuli. However, whether poor sleep affects false memory production in a task-dependent manner (i.e., free recall or recognition) remains unclear. METHODS: Through an online research method, we adopted the classical DRM paradigm to investigate the production of false recalls and false recognitions in 32 subjects referring insomnia symptoms (IN group) and 37 good sleepers (GS group), addressing also executive functioning and source monitoring ability in both groups. RESULTS: Compared to the GS group, the IN group produced more false memories (p = .002) and intrusions (p = .004) at the free recall task and showed a lower working memory index (p = .008). No between-groups differences emerged at the recognition task. Correlational analysis revealed significant associations between DRM performance, executive functioning and source monitoring (SM) variables. Moreover, false recalls were predicted by being in the presence of insomnia symptoms (p = .012) and intrusions by the number of correct responses to the Stroop task (p = .051) and SM task (p = .015), as well as by the presence of insomnia symptoms (p = .003). CONCLUSIONS: Our data show that the presence of insomnia symptoms can influence false memories production. Furthermore, the evidence that free recall is more affected than recognition suggests that poor sleep mainly affects performance at more cognitively demanding tasks. Finally, correlational and regression analyses support the hypothesis of a link between false memories production and both the presence of insomnia symptoms and executive functioning impairments.