Dream Emotions Research Articles

A novel method for objectively classifying sequential emotion within dreams: a proof-of-concept pilot study.

Traditionally, emotions in dreams have been assessed using subjective ratings by human raters (e.g., external raters or dreamers themselves). These methods have extensive support and utility in dream science, yet they have certain innate limitations due to the subjective nature of the rating methodologies. Attempting to circumvent several of these limitations, we aimed to develop a novel method for objectively classifying and quantifying sequential (word-for-word) emotion within a dream report. We investigated whether sentiment analysis, a branch of natural language processing, could be used to generate continuous positive and negative valence ratings across a dream. In this pilot, proof-of-concept study, we used 14 dream reports collected upon awakening following overnight polysomnography. We also collected pre- and post-sleep affective data and personality metrics. Our objectives included demonstrating that (1) valence ratings derived from sentiment analysis (Valence Aware Dictionary for sEntiment Reasoning [VADER]) could be used to visualize (plot) positive and negative emotion fluctuations within a dream, (2) how the visual properties of emotion fluctuations within a dream (peaks and troughs, area under the curve) can be used to generate novel "emotion indicators" as proxies for emotion regulation throughout a dream, and (3) these emotion indicators correlate with sleep, affective, and personality variables known to be associated with dreaming and emotion regulation. We describe 6 novel, objective dream emotion indicators: Total number of Peaks, total number of Troughs, Positive, Negative, and Overall Emotion Intensity (composites from an "area under the curve" method using the trapezoid rule applied to the peaks and troughs), and the Emotion Gradient (a polynomial trendline fitted to the emotion fluctuations in the dream chart). The latter signifies the overall direction of sequential emotion changes within a dream. Results also showed that ⅚ emotion indicators correlated significantly with at least one existing sleep, affective, or personality variable known to be associated with dreaming and emotion regulation. We propose that the novel emotion indicators potentially serve as proxies for emotion regulation processes unfolding within a dream. These preliminary findings provide a methodological foundation for future studies to test and refine the method in larger and more diverse samples.

Dream habits in a large cohort of preteens and their relation to sleep and nocturnal awakenings.

The present study examined dream habits, and their relation to sleep patterns, in 1151 preteens (597 boys; 554 girls; 11.31 ± 0.62 years old). Dream questionnaires assessed the frequency of dream recall, nightmare, and lucid dream, as well as the intensity of emotions experienced in dreams. Sleep variables included sleep duration and efficiency, but also different measurements of nocturnal awakenings. Among the preteens, 49.21% of them reported that they recalled dreams several times a week or almost every morning over the past few months. In addition, 52.00% of the preteens reported that they experienced nightmares, and 45.48% lucid dreams, less than once a month or never over the past few months. No gender differences were observed in dream variables. Nocturnal awakenings were linked to all dream variables, while sleep duration and sleep efficiency were related to nightmare frequency and emotions in dreams. Importantly, sleep duration and sleep efficiency were not associated with dream recall nor lucid dream frequency, with Bayesian analyses supporting the null hypothesis. These findings offer a comprehensive understanding of preteens' dreams and their connection to key sleep aspects.

Dreaming in Bipolar Disorders - Feasibility of the Central Image Method: A Prospective Controlled Trial.

Emotions play an important role in the emergence, formation, and experience of dreams. The Central Image (CI) in a dream refers to the dream's dominant or underlying emotion, and it is the best-remembered part of a dream. Bipolar disorders are characterized by strong emotions, particularly during manic and depressive episodes. In these patients, dreams and CIs may serve as a helpful diagnostic and therapeutic tool. This study aims to evaluate the feasibility of the CI Method and to check for differences concerning dreams and CI emotions between healthy controls and patients with bipolar disorder. Over a period of 3 weeks, 61 participants were asked to maintain a daily record of all dreams remembered. Dream reports were rated using the Central Image Method (CIM) by two independent, blinded raters. We assessed for interrater agreement on the CIM and for within and between group differences related to negative and positive CI emotions. Mean agreement rates (weighted Cohen's kappa) for the CI emotion ratings could be classified as very good: For primary CI emotion ratings, the mean weighted Cohen's kappa was 0.99 (± 0.02), and for secondary CI emotions, it was 0.90 (± 0.17). Regarding the CI intensities, the mean agreement rate (Spearman's correlation) was also strong. Evaluation of differences within the groups showed that there were more negative CI emotions than positive CI emotions in healthy controls and currently depressive patients; however, in the latter, the difference was statistically not significant. Analyses of differences between groups indicated that patients who were currently depressed recorded more negative CI emotions in dreams than those who were euthymic or healthy controls. The findings support the feasibility of the CIM. Our results might indicate different emotion regulation and defense mechanisms across bipolar disorder states, as reflected by the occurrence of negative and positive CI emotions.

Are dream emotions fitting?

ABSTRACT When we dream, we feel emotions in response to objects and events that exist only in the dream. One key question is whether these emotions can be said to be “essentially unfitting”, that is, always inappropriate to the evoking scenario. However, how we evaluate dream emotions for fittingness may depend on the model of dreams we adopt: the imagination or the hallucination model. If fittingness requires a match between emotion and evaluative properties of objects or events, it is prima facie plausible that dream emotions could fail to fit under the imagination model because it is unfitting to have an emotion toward an object we do not believe to be real. Under the hallucination model, dream emotions could be unfitting because their objects do not exist but we believe them to be real. More nuance, however, is required. By comparing dream emotions with the emotions we experience while imagining, engaging with fiction, and hallucinating, we conclude that although there are compelling arguments in support of the claim that dream emotions are essentially unfitting, these arguments are not entirely convincing, and it is more plausible that particular dream emotions can be assessed for fittingness under either model of dreaming.

Dreamtelling: The value of dreaming and sharing dreams in relations: Part I: From collective preoccupations to shared dreaming

This article looks at the group approach to shared dreams following previous publications, including Dreams In Group Psychotherapy: Theory and Technique (Neri et al. 2002) and further papers1, and a natural extension to a 2022 publication (Friedman, 2022). One innovative perspective is the notion that it is often a ‘collective preoccupation’ which starts a group’s shared elaboration process (dreaming), which to begin with is transmitted through interpersonal and transpersonal communication to a delegated dreamer. Another new perspective is to view dreaming (mental digestion) as the main process of a revised four step ‘dream cycle’. The dream cycle goes from collective preoccupation, through personal dreaming, then through an inner narrative, followed by a potentially shared relational elaboration. This helps to understand that ‘dreamtelling’ is only the fourth step in the shared process of mental ‘digestion’ of peoples’ excessive threats/excitements. In Part I I describe the central approach to a shared dream in group analysis as ‘personal responses first’, meaning the predilection of a free-floating discussion of a dream, involving the whole group’s conscious and unconscious mirroring and resonance, while postponing traditional interpretation. Dreams should be understood as both the result and the motor of group processes. Through the joint elaboration of collective preoccupations, dreams that are shared can contribute to the reciprocal healing of relation disorders and dysfunctional relational patterns. I will describe the four-step ‘dream cycle’, which changes the location of mental digestion. By putting transpersonal and interpersonal communication into action, the individual’s and the group’s mind develops (Köhncke and Mies, (2012)). In the final phase, preoccupying situations and conflictual emotions in dreams are elaborated by free discussion, ‘personal responses first’ which is ‘open communication’ in relational configurations in the ‘society of individuals’ (Elias,1939). This process, which I call ‘dreamtelling’, describes discourse (Schlapobersky, 1993) with potential partners who will ‘(re)dream the dream’, and offer further digestion of the collective preoccupation. A series of clinical vignettes discuss notions such as ‘the location of elaboration’ moves in the relations, e.g. ‘dreaming for others’ and ‘delegation’ as well as the notion of an ‘inner group’ and the unconscious communication between dreamers and listeners. In Part II, I provide deeper exploration of a clinical example in group-analytic group therapy, describing group work with a dream. The uniqueness of the group-analytic approach to the dream’s contents and its communicative aspect will be stressed. Requests for containment preoccupy relations and participants and should be differentiated during the discourse of ‘dreamtelling’.

Nocturnal exposure to a preferred ambient scent does not affect dream emotionality or post-sleep core affect valence in young adults

Emotions experienced within sleep mentation (dreaming) affect mental functioning in waking life. There have been attempts at enhancing dream emotions using olfactory stimulation. Odors readily acquire affective value, but to profoundly influence emotional processing, they should bear personal significance for the perceiver rather than be generally pleasant. The main objective of the present sleep laboratory study was to examine whether prolonged nocturnal exposure to self-selected, preferred ambient room odor while asleep influences emotional aspects of sleep mentation and valence of post-sleep core affect. We asked twenty healthy participants (12 males, mean age 25 ± 4 years) to pick a commercially available scented room diffuser cartridge that most readily evoked positively valenced mental associations. In weekly intervals, the participants attended three sessions. After the adaptation visit, they were administered the odor exposure and odorless control condition in a balanced order. Participants were awakened five minutes into the first rapid eye movement (REM) stage that took place after 2:30 a.m. and, if they had been dreaming, they were asked to rate their mental sleep experience for pleasantness, emotional charge, and magnitude of positive and negative emotions and also to evaluate their post-sleep core affect valence. With rs < 0.20, no practically or statistically significant differences existed between exposure and control in any outcome measures. We conclude that in young, healthy participants, the practical value of olfactory stimulation with self-selected preferred scents for enhancement of dream emotions and post-sleep core affect valence is very limited.

Associations Between Both Adaptive and Maladaptive Personality Constructs and Emotional Load and Content of Adult Dreams

Background: It seems that personality and dreams are relatively stable interwoven constructs that show many shared characteristics across cultures. The present study aimed to predict the emotional load and content of dreams using both original constructs and two extracted spectrum factors of adaptive and maladaptive personalities. Methods: The cross-sectional study data was collected from 704 Iranian adults using the brief version of the Personality Inventory for DSM-5, the brief version of the Big Five Inventory, Schredl’s Dream Emotions Manual, and the Content Analysis of Dreams Manual. Pearson correlations, hierarchical regressions, exploratory factor analysis, and analysis of variance were used to analyse the data. Results: Factor analysis revealed two factors for the adaptive and maladaptive spectrums of personality. Adaptive and maladaptive constructs of personality are almost equally related to both the negative and positive loads of dreams, while the negative load of dreams is more strongly predicted by the maladaptive spectrum factor ( R2: 13% vs. 7%, ∆ R2: 8% vs. 2%). Negative load is characterized by low agreeableness and high negative affectivity, while positive load is characterized by high agreeableness and low detachment. Compared to most negative dream content such as distress, dreamers with happy content reported higher adaptive traits and lower maladaptive traits. Conclusions: The emotional load and content of dreams are significantly related to both specific constructs and spectrum factors of adaptive and maladaptive personalities. Psychologists can refer to personality profiles when analysing the emotional load and content of dreams of adults.

Relationship between trait anxiety and emotions in dreams, evaluated in older adults.

Relationship between trait anxiety and emotions in dreams, evaluated in older adults.

Alexithymia and aspects of dreaming: Differential associations of alexithymia facets with dream variables.

Research on aspects of dreaming associated with alexithymia has yielded mixed results. The present study recruited a young adult online sample of 577 participants who completed validated indices of alexithymia, emotion suppression, negative moods, and eight aspects of dreaming, with a focus on evaluating a counterintuitive previous finding that alexithymia and two of its core facets were associated with greater self-reported typical emotional intensity of dreams. Total alexithymia and facet scores showed differential relationships to aspects of dreaming including dream recall frequency, emotionality, meaningfulness, nightmare frequency, nightmare distress, usefulness of dreams in problem-solving and creativity, and learning about oneself through dreams. Planned hierarchical regression controlling for demographics, alcohol use, and dream recall frequency indicated that the difficulties identifying feelings (DIF) facet of alexithymia was a significant positive predictor of dream emotionality, whereas the externally oriented thinking (EOT) facet was a significant negative predictor. Stress, but not emotion suppression, mediated the positive relationship between DIF and dream emotionality. The likely role of dream emotionality in higher ratings of nightmare distress, dream meaningfulness, and learning about oneself through dreams among those with higher DIF scores is noted, along with other findings and the strengths and limitations of the study.

Subjectively intense odor does not affect dream emotions during rapid eye movement sleep

Dreams experienced during rapid eye movement (REM) sleep have emotional features. Intervention methods for dream affectivity have recently garnered interest; we previously demonstrated that negative dreams were induced during REM sleep by exposure to favorable or familiar odors. However, the underlying mechanisms behind this phenomenon remain unclear. Thus, to address this gap, we investigated whether more intense odors could induce negative dreams, as odors tend to be perceived as more intense when they are preferred or familiar. Contrary to our hypothesis, the results of our study indicated that subjective intense odors did not induce negative dreams. We initially anticipated stronger odors to have a greater impact on dream emotionality, as they stimulate the brain more intensely. Notably, during arousal, weak odors tended to evoke a more potent olfactory response, while strong odors tended to produce a weaker response. To investigate whether this difference influenced the effects on dreams, we compared the respiratory activities of the strongly and weakly perceived odor groups; however, no significant differences were observed. Our findings suggest that subjectively perceived strong odors are unlikely to affect dream emotionality and may be processed differently than favorable or familiar odors.

The dynamics of emotional behaviors in rapid eye movement sleep.

Dream's emotions could exert a major role in desensitizing negative emotions. Studying emotional dynamics (how emotions fluctuate across time) during rapid eye movement (REM) sleep could provide some insight into this function. However, studies so far have been limited to dream reports. To bypass this limit, REM sleep behavior disorder (RBD), in which participants enact their dreams, enables direct access to overt emotional dream behaviors (such as facial expressions and speeches). In total, 17 participants with RBD, and 39.7 h of REM sleep video were analyzed. The frequency of emotional behaviors did not differ between REM sleep episodes of early and late night. Within individual REM sleep episodes, emotional behaviors exhibited a biphasic temporal course, including an increased frequency for the first 10 min, followed by a progressive decrease. The negative emotional behaviors occurred earlier (mean time: 11.3 ± 10 min) than positive (14.4 ± 10.7 min) and neutral behaviors (16.4 ± 11.8 min). Emotional behaviors of opposing (negative and positive) valences were observed in 31% (N = 14) of episodes containing at least one emotional behavior, and were separated by a median time of 4.2 [1.1-10.9] min. The biphasic temporal course of behaviors in REM sleep could include the generation reactivation of emotional content during the ascending phase, followed by processing and extinction during the descending phase. The earlier occurrence time of negative emotional behavior suggests that negative emotions may need to be processed first. The rapid succession of emotions of opposite valence could prevent prolonged periods of negative emotions and eventually nightmares.

Nightmare distress is related to traumatic childhood experiences, critical life events and emotional appraisal of a dream rather than to its content.

Nightmares are a substantial burden for sleep quality. Previous studies have shown that traumatic experiences can increase the probability of nightmares, and also waking-life distress can enhance this effect. There is evidence that the intensity of negative dream emotions is more responsible for rating a dream as a nightmare than threatening dream contents. However, there is still a lack of research concerning effects on nightmare distress. We hypothesise that traumatic childhood experiences (such as emotional abuse, obtained by the Childhood Trauma Questionnaire), critical life events (obtained by the Social Readjustment Rating Scale) and threatening dream contents are associated with nightmare distress. A sample of N= 103 participants kept a dream diary over 28 consecutive days. About 60% of the sample were frequent nightmare dreamers. The participants recorded their violent dream contents and dream emotions in their diary. To predict nightmare distress, regression models were constructed; nightmare distress was measured with the Nightmare Distress Questionnaire. Results showed that emotional abuse in childhood and critical life events predicted nightmare distress. Moreover, violent dream contents were associated with nightmare distress but, after we controlled for nightmare frequency and the intensity of negative dream emotions, the significant impact of violent dream contents decreased. The results suggest that the emotional appraisal of a dream has a substantial influence on nightmares in addition to traumatic childhood experiences and critical life events.

Enhancing imagery rehearsal therapy for nightmares with targeted memory reactivation

Nightmare disorder (ND) is characterized by dreams with strong negative emotions occurring during rapid eye movement (REM) sleep. ND is mainly treated by imagery rehearsal therapy (IRT), where the patients are asked to change the negative story line of their nightmare to a more positive one. We here used targeted memory reactivation (TMR) during REM sleep to strengthen IRT-related memories and accelerate remission of ND. Thirty-six patients with ND were asked to perform an initial IRT session and, while they generated a positive outcome of their nightmare, half of the patients were exposed to a sound (TMR group), while no such pairing took place for the other half (control group). During the next 2weeks, all patients performed IRT every evening at home and were exposed to the sound during REM sleep with a wireless headband, which automatically detected sleep stages. The frequency of nightmares per week at 2weeks was used as the primary outcome measure. We found that the TMR group had less frequent nightmares and more positive dream emotions than the control group after 2weeks of IRT and a sustained decrease of nightmares after 3months. By demonstrating the effectiveness of TMR during sleep to potentiate therapy, these results have clinical implications for the management of ND, with relevance to other psychiatric disorders too. Additionally, these findings show that TMR applied during REM sleep can modulate emotions in dreams.

Supplemental Material for Experience of Emotions in Dreams: An Empirical Phenomenological Study

Supplemental Material for Experience of Emotions in Dreams: An Empirical Phenomenological Study

Dreamers' evaluation of the emotional valence of their day-to-day dreams is indicative of some mood regulation function.

Dreams may contribute to psychological adaptation by aiding in mood regulation. One way it could be achieved is through a desensitization process whereby negative events are replayed within the dream under lower conditions of negative emotionality. Evidence of this theory is supported by the tendency of dreamers to evaluate their emotions felt in their dreams more positively compared to an independent judge (i.e., positivity bias). Additionally, it has been observed that while dream emotions are typically more negative than pre-sleep emotions, morning emotions are more positive, suggesting that emotional regulation occurs overnight and may help improve mood in the morning. The present study aimed to examine the relationships between pre-sleep, dream, and morning mood and the potential desensitization function of remembered dreams as indicated by their effects on morning mood and stress.Methodology: Participants (N = 188; Mean age = 19.2, SD = 3.0) recorded their dreams (N = 345 dreams) and self-reported their stress and mood at bedtime, during their dream retrospectively, and upon waking. A judge also evaluated the subjects’ dream moods. Subjects’ positivity bias was defined as the difference between the subjects and the judge’s evaluation of the positive emotions in the dream.Results: A MANOVA revealed that subjects perceived a higher level of positive emotions in their dreams compared to a judge. Multi-group path analysis revealed that some relationships between pre-sleep, dream, and morning emotions and stress differed in positive and negative dream nights. In both groups, the strongest predictors of morning mood and stress were pre-sleep mood and stress, respectively. The second strongest predictor of positive morning mood was the subjects’ dream positivity bias.Conclusion: Results provide some support for the association of dreaming in mood regulation attributable to REM sleep. They also highlight that pathways implicated in mood regulation may be distinct from stress regulation.

Dreaming and Sleep-Related Metacognitions in Patients with Sleep Disorders.

Sleep-related metacognitions play a role in the etiology of insomnia and are distressing while falling asleep. Although similar concepts, such as thought suppression, have been studied in the context of dreaming, the relationship between sleep-related metacognitions and more negatively toned dreaming due to stressful pre-sleep experiences has yet to be studied. Overall, 919 patients with various sleep disorders completed the Metacognitions Questionnaire-Insomnia (MCQ-I20), Arousal Disposition Scale (APS), and Pre-Sleep Arousal Scale (PSAS) and kept a sleep diary over seven days eliciting dream recall, nightmare frequency, and the emotional tone of their dreams. The regression analysis showed that the MCQ-I20 (small effect size) and the APS (medium effect size) were associated with nightmare frequency and negatively toned dream emotions. These findings suggest that dysfunctional sleep-related metacognitions that are active prior to sleep are also associated with more negatively toned dreaming and more nightmares—even after controlling for trait arousability. It would be very interesting to study where therapeutic strategies, such as metacognitive therapy explicitly targeting sleep-related metacognition, could also be beneficial with regard to dreams (more positive dreams and fewer nightmares).

Targeted Memory Reactivation During REM Sleep in Patients With Social Anxiety Disorder.

BackgroundSocial anxiety disorder (SAD) is characterized by a significant amount of fear when confronted to social situations. Exposure therapy, which is based on fear extinction, does not often lead to full remission. Here, based on evidence showing that rapid eye movement (REM) sleep promotes the consolidation of extinction memory, we used targeted memory reactivation (TMR) during REM sleep to enhance extinction learning in SAD.MethodsForty-eight subjects with SAD were randomly assigned to two groups: control or TMR group. All patients had two successive exposure therapy sessions in a virtual reality (VR) environment, where they were asked to give a public talk in front of a virtual jury. At the end of each session, and only in the TMR group (N = 24), a sound was paired to the positive feedback phase of therapy (i.e., approval of their performance), which represented the memory to be strengthened during REM sleep. All participants slept at home with a wearable headband device which automatically identified sleep stages and administered the sound during REM sleep. Participants' anxiety level was assessed using measures of parasympathetic (root mean square of successive differences between normal heartbeats, RMSSD) and sympathetic (non-specific skin conductance responses, ns-SCRs) activity, and subjective measures (Subjective Units of Distress Scale, SUDS), during the preparation phase of their talks before (T1) and after (T2) one full-night's sleep and after 1 week at home (T3). Participants also filled in a dream diary.ResultsWe observed an effect of time on subjective measures of anxiety (SUDS). We did not find any difference in the anxiety levels of the two groups after 1 week of TMR at home. Importantly, the longer the total duration of REM sleep and the more stimulations the TMR group had at home, the less anxious (increased RMSSD) these participants were. Finally, fear in dreams correlated positively with ns-SCRs and SUDS at T3 in the TMR group.ConclusionTMR during REM sleep did not significantly modulate the beneficial effect of therapy on subjective anxiety. Yet, our results support that REM sleep can contribute to extinction processes and substantiate strong links between emotions in dreams and waking stress levels in these patients.

Schizotypy unfolding into the night? Schizotypal traits and daytime psychotic-like experiences predict negative and salient dreams

Symptoms of insomnia and frequent nightmares are prevalent in psychotic disorders, and are associated with psychotic-like experiences (PLEs) in the non-clinical population. Whereas the role of impaired sleep in psychosis was extensively examined by longitudinal and interventional approaches, studies on the association between psychosis and dream quality are scarce, and mainly cross-sectional. We conducted a three-week long prospective study in a group of healthy adults (N = 55), assessed schizotypal traits, daily PLEs, and the emotional quality of dreams recalled in the morning (N = 490). We extracted the latent factors of schizotypal traits and dream emotions, and examined the predictive value of trait-and state-like variables on day-to-day reports of PLEs and dream quality. PLEs reported in the evening predicted emotionally more negative and salient dream reports the following morning. On the other hand, the quality of dreams were not predictive of PLEs reported later during the day. Schizotypal personality traits were differentially associated with dream quality: Introvertive Anhedonia, Cognitive Disorganization, and General-Disorganized schizotypy were linked to more negative dream valence, whereas Unusual Experiences were associated with more salient dreams. Our findings highlight the relevance of the multidimensional nature of schizotypal traits, the role of different facets of schizotypy in daytime and nocturnal mental experiences, and the day-to-day associations between PLEs and dream affect. General scientific summaries (GSS)The aim of the study was to examine the temporal associations between psychotic-like experiences and dream emotions, taking into account the trait factors of schizotypy. Psychotic-like experiences during the evening hours predicted reporting more negative and salient dreams the following morning, and schizotypal personality traits were differentially associated with the dimensions of dream emotions.

Dissociated Effects of Age and Recent Troubling Experiences on Nightmares, Threats and Negative Emotions in Dreams.

Several studies have highlighted associations between adverse life events and the dysphoric character of dream experiences. This degree of continuity between waking-life and dream content seems partly attributed to the emotional and personal attachment linked to the incorporated waking experiences. Numerous changes in the processing of emotion-related stimuli are also reported across different human developmental stages. Therefore, we were interested in testing whether age would modulate the impact of recent troubling experiences on dream characteristics. Two hundred sixty participants, evenly distributed in five developmental stages, matched for gender and their exposure to a troubling experience, were selected from a large sample collected for a previous normative study of dreams of Canadians. Participants completed a dream questionnaire from which independent judges subsequently scored the dreams. We observed no interactions between the experience of troubling events and age. However, individuals who experienced a recent troubling event reported a higher frequency of nightmares and their dreams were more emotionally negative. Participants who experienced a moderately severe troubling event were also more likely to experience a dream whose maximal threat severity was of moderate intensity. Adolescents and young adults had dreams with a higher level of oneiric threats compared to older adults (>40 years old). Young adults also reported a higher frequency of nightmares compared to older adults. Our findings have implications for modern dream theories. They also suggest that dysphoric dreams might serve as potential proxies of mental health status and developmental stages. Future studies are now needed to explore the implications of these findings for psychological adaptation.

Eye movement patterns correlate with overt emotional behaviours in rapid eye movement sleep

Growing evidence suggests that sleep plays a key role in regulating emotions. Rapid eye movements (REMs) in REM sleep could be associated with dreams emotions, but supporting evidence is indirect. To highlight this association, we studied the REM sleep during video-polysomnography of 20 subjects with REM sleep behaviour disorder (RBD), a model of enacted dreams offering direct access to the emotional content of the sleeper (face expression, speeches, behaviour). Video and the electro-oculography recordings were divided into 3 s time intervals and classified as non-behavioural, or behavioural (neutral, positive or negative emotions), and as containing no eye movements (EMs), slow eye movements (SEMs) or REMs (isolated or bursts). Compared to the absence of EMs, neutral behaviours successively increased in the presence of SEMs (odd ratio, OR = 1.4), then isolated REMs (OR = 2.8) and then REM bursts (OR = 4.6). Positive behaviours increased with SEMs (OR = 2.8) but did not increase further with isolated REMs (OR = 2.8) and REM bursts (OR = 3). Negative behaviours were absent with SEMs, increased with isolated REMs (OR = 2.6) and further with REM bursts (OR = 10.1). These results support an association between REMs and SEMs, and dream emotions.