No abstract

A lucid dream is a dream in which one is conscious of dreaming and can possibly control the dream or passively observe its unfolding. Frequencies of lucid dreaming (LD), dream with awareness, and dream with actual control were previously investigated in a French student population. As a student population usually differs on oneiric and sleep characteristics (such as sleep quality) from the general population, more investigations were needed. Additionally, it is yet unresolved if LD is related to one's overall sleep quality. This study aims at describing and comparing dream experience frequencies (dream, lucid dreams, awareness, and control) and sleep quality assessed with the Pittsburgh Sleep Quality Index (PSQI) among students (n = 274) and in a general population sample (n = 681). It also aims at evaluating if dream experience frequencies can predict sleep quality across these two samples. Predictive models of PSQI score controlling for age and gender were not significant in the student group while they were all marginally predictive for the general population. However, none of these models showed that the frequency of dream experiences could actually help predict the quality of sleep as the significance of the model was carried over only by the gender variable. These results are discussed in line with previous studies on LD frequencies. Several methodological adjustments for future study are proposed.

Lucid dreaming (LD) is a state of consciousness in which the dreamer is aware that he or she is dreaming and can possibly control the content of his or her dream. To investigate the LD prevalence among different samples, researchers have used different types of methodologies. With regard to retrospective self-report questionnaire, two ways of proceeding seem to emerge. In one case, a definition of LD is given to participants (“During LD, one is–while dreaming–aware of the fact that one is dreaming. It is possible to deliberately wake up, to control the dream action, or to observe passively the course of the dream with this awareness”), while in the other instances, participants are presented separate questions targeting specific LD indicators (dream awareness and dream control). In the present study, we measured LD frequency in a sample of French student in order to investigate for possible disparities in LD frequency depending on the type of questionnaire as outlined above. Moreover, we also study links between the prevalence of LD as assessed, respectively, by each questionnaire with various factors such as Vividness of Mental Imagery and Parasomnia. Results revealed no significant difference between LD frequencies across questionnaires. For the questionnaire with definition (DefQuest), 81.05% of participants reported experience of LD once or more. Concerning the questionnaire based on LD indicators (AwarContQuest), 73.38% of participants reported having experienced LD once or more. However, with regard to the correlations analysis, links between LD prevalence and factors such as Vividness of Mental Imagery and Parasomnia, varied across questionnaires. This result is an argument suggesting that researchers should be careful when investigating links between LD and other factors. The type of methodology may influence findings on LD research. Further studies are needed to investigate on the methodology effect in LD research namely on the respective weight of awareness and control.

This study evaluated the effect of sleep in mediating episodic memory performances in a recognition task of visually associated and related elements. It also considered links between memory performances, dreams mentation, and emotional salience of items. Two groups of participants were studied; in the wake group, they stayed awake on a normal day, and in the sleep group, they slept at home according to their usual sleep schedule and context. Compared with the wake group, participants in the sleep group performed better in the delayed associative and relational tests. Negative and positive emotional images were better recognized by the participants than neutral ones with no group specificity. Examination of dream reports suggested that reporting a dream related to the present study was associated with an increase in recognition performances. Overall, our research demonstrated how new associative and relational links can be consolidated in memory following a full night’s sleep.

A challenge for cognitive research is the better understanding of how motor activity influences and is influenced by other cognitive domains. We developed a preliminary study to investigate whether tracking motor functioning in virtual reality provides useful insight on cognitive functioning. We chose the flankers task as an assessment measure and built a VR environment into which seven participants completed more than 1250 trials. In addition to classical results of the flankers task showing that incongruent stimuli induce slower responses than others., we also identified how individuals are able to correct their initially incorrect motor response. This indicator may shed new light into the functioning of cognitive control in the future. We discuss the potential offered by virtual reality technology for cognitive assessment through embodied considerations of cognition.