False memories formation is increased in individuals with insomnia.

Previous studies suggest that sleep can influence false memories formation. Specifically, acute sleep loss has been shown to promote false memories production by impairing memory retrieval at subsequent testing. Surprisingly, the relationship between sleep and false memories has only been investigated in healthy subjects but not in individuals with insomnia, whose sleep is objectively impaired compared to healthy subjects. Indeed, this population shows several cognitive impairments involving prefrontal functioning that could affect source monitoring processes and contribute to false memories generation. Moreover, it has been previously reported that subjects with insomnia differentially process sleep-related versus neutral stimuli. Therefore, the aim of the present study was to compare false memories production between individuals with insomnia symptoms and good sleepers, and to evaluate the possible influence of stimulus category (neutral versus sleep-related) in the two groups. The results show that false memories are globally increased in participants reporting insomnia symptoms compared to good sleepers. A reduction in source monitoring ability was also observed in the former group, suggesting that an impairment of this executive function could be especially involved in false memories formation. Moreover, our data seem to confirm that false memories production in individuals with insomnia symptoms appears significantly modulated by stimulus category.