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Emotional facial expressions during REM sleep dreams
Journal of Sleep Research
Abstract
Although motor activity is actively inhibited during rapid eye movement (REM) sleep, specific activations of the facial mimetic musculature have been observed during this stage, which may be associated with greater emotional dream mentation. Nevertheless, no specific biomarker of emotional valence or arousal related to dream content has been identified to date. In order to explore the electromyographic (EMG) activity (voltage, number, density and duration) of the corrugator and zygomaticus major muscles during REM sleep and its association with emotional dream mentation, this study performed a series of experimental awakenings after observing EMG facial activations during REM sleep. The study was performed with 12 healthy female participants using an 8‐hr nighttime sleep recording. Emotional tone was evaluated by five blinded judges and final valence and intensity scores were obtained. Emotions were mentioned in 80.4% of dream reports. The voltage, number, density and duration of facial muscle contractions were greater for the corrugator muscle than for the zygomaticus muscle, whereas high positive emotions predicted the number (R2 0.601, p = 0.0001) and voltage (R2 0.332, p = 0.005) of the zygomaticus. Our findings suggest that zygomaticus events were predictive of the experience of positive affect during REM sleep in healthy women.
... This perspective was also strengthened by a recent study investigating the activations of facial mimetic musculature during REM sleep as electrophysiological marker of emotional dreams (Rivera-García et al., 2018). The presence of specific facial expression during this stage can be interpreted as a Dream Enacting Behaviors (DEBs), namely the behavioral enactment of the emotional, verbal or motor components of complex dreams Nir and Tononi, 2010). ...
... The presence of specific facial expression during this stage can be interpreted as a Dream Enacting Behaviors (DEBs), namely the behavioral enactment of the emotional, verbal or motor components of complex dreams Nir and Tononi, 2010). A growing body of literature suggests that DEBs are more frequent during nightmares or high emotionally intense dreams, providing a background to study the relation between DE and emotional processing Rivera-García et al., 2018). Rivera-García et al. (2018) analyzed the facial EMG signals along with the standard PSG measures, finding that the activation of corrugator and zygomaticus facial muscles during REM sleep occurs when the incidence of emotional DE is higher (Rivera-García et al., 2018). ...
... A growing body of literature suggests that DEBs are more frequent during nightmares or high emotionally intense dreams, providing a background to study the relation between DE and emotional processing Rivera-García et al., 2018). Rivera-García et al. (2018) analyzed the facial EMG signals along with the standard PSG measures, finding that the activation of corrugator and zygomaticus facial muscles during REM sleep occurs when the incidence of emotional DE is higher (Rivera-García et al., 2018). Besides, this study -examining a wider range of emotions-confirmed that the peak rates in healthy population corresponded to the high negative emotional contents (Rivera-García et al., 2018). ...
Dream experience (DE) represents a fascinating condition linked to emotional processes and the human inner world. Although the overlap between REM sleep and dreaming has been overcome, several studies point out that emotional and perceptually vivid contents are more frequent when reported upon awakenings from this sleep stage. Actually, it is well-known that REM sleep plays a pivotal role in the processing of salient and emotional waking-life experiences, strongly contributing to the emotional memory consolidation. In this vein, we highlighted that, to some extent, neuroimaging studies showed that the processes that regulate dreaming and emotional salience in sleep mentation share similar neural substrates of those controlling emotions during wakefulness. Furthermore, the research on EEG correlates of the presence/absence of DE and the results on EEG pattern related to the incorporated memories converged to assign a crucial role of REM theta oscillations in emotional re-processing. In particular, the theta activity is involved in memory processes during REM sleep as well as during the waking state, in line with the continuity hypothesis. Also, the gamma activity seems to be related to emotional processes and dream recall as well as to lucid dreams. Interestingly, similar EEG correlates of DE have been found in clinical samples when nightmares or dreams occur. Research on clinical samples revealed that promoting the rehearsal of frightening contents aimed to change them is a promising method to treat nightmares, and that lucid dreams are associated with an attenuation of nightmares. In this view, DE can defuse emotional traumatic memories when the emotional regulation and the fear extinction mechanisms are compromised by traumatic and frightening events. Finally, dreams could represent a sort of simulation of reality, providing the possibility to create a new scenario with emotional mastery elements to cope with dysphoric items included in nightmares. In addition, it could be hypothesized that the insertion of bizarre items besides traumatic memories might be functional to “impoverish” the negative charge of the experiences.
... Consequently, limited research has been conducted on the bidirectional links between daytime affect and affect during sleep. Specifically, regarding affect during sleep, the available evidence relies dominantly on retrospective selfreports [16], contact-based approaches such as facial electromyography (EMG) [17] and paradigms deploying instrumental awakenings during sleep [18]. While self-reports rely on introspection, contact-based measures can interfere with sleep quality, underscoring the need for innovative research approaches. ...
Clinical research demonstrates the bidirectional associations between affect and sleep: Major depressive disorder is a prevalent clinical disorder, characterized by alterations in affect and sleep. Conversely, sleep disturbances emerge as prodromal manifestations preceding the onset of the disorder. Despite these close links, few studies investigated depressed daytime affect and its bidirectional associations with sad affect at the time of sleep. This lack of evidence can be attributed to methodological constraints, challenging the assessment of affect during sleep. To address this research gap, the present study introduces an innovative method utilizing Machine Learning and Infrared technology for the unobtrusive assessment of affect during sleep. The objectives of the present proof of concept were as follows: First, to introduce a novel approach for measuring affect during sleep. Second, to determine the bidirectional associations of depressed affect at daytime and sad affect during sleep in a healthy sample. Sad affect during sleep was measured using three infrared cameras with adaptive night vision, recording 63 videos during sleep. Daytime depressed affect was measured by survey, data analysis included general linear modeling (GLM). In line with the first objective, sad affect during sleep was extracted from video-based facial expressions using Artificial Intelligence software frameworks open DBM and open Face (AiCure). In line with the second objective, GLM analysis yielded that higher levels of depressed affect at daytime predicted higher levels of sad affect during sleep significantly. The inverse association was not significant. Conclusionally, we present an innovative method for the unobtrusive measurement of affect during sleep. This method may be particularly advantageous for the early detection of depressed mood states in subclinical populations and samples undergoing transient depressed mood states. Clinical and general implications are discussed.
... Research suggests that dreamed actions involving eye gaze and facial expressions exhibit physiological parallels with the physical body (Arnulf, 2011;Dement & Kleitman, 1957). Similarly, facial muscle activations associated with emotions, such as smiling or frowning, have been observed to mirror the dream content (Rivera et al., 2018). During rapid eye movement (REM) sleep, which is associated with vivid dreaming, bodily responses such as changes in heart rate, respiration, and muscle activity can mirror the experienced dream content (Erlacher & Schredl, 2008). ...
The connection between the dreamed body and the real physical body remains a subject of ongoing investigation. This study explored how the dreamed body responds to somatosensory stimulation of the physical body, aiming to shed light on the sensory processes that shape our dreaming experiences. We employed a novel within-subject design to compare the incorporation of three different types of bodily stimuli—electrical muscular, galvanic vestibular, and haptic vibration—into dream content, alongside a control sham condition for each stimulus. In total, 24 participants spent one adaptation night, followed by three consecutive test nights in the sleep laboratory. REM awakenings, after sham or stimulation periods, were carried out for dream report collection. In total, 165 dream reports were collected across conditions. While dream incorporation was observed across the three stimulation methods, it occurred equally in both the stimulation and sham conditions for all three modalities. These findings highlight broader methodological challenges in dream incorporation research and raise concerns about potential confounding factors affecting the interpretation of results. Future research with larger sample sizes is needed to detect smaller effect sizes and fully understand the influence of these somatosensory stimuli on dream content. This study employed a rigorous experimental approach to exploring dream incorporation and addressed many methodological challenges in this area. We further suggest areas of improvement to optimize dream incorporation of different sensory modalities.
Graphical Abstract
... Although REM sleep is characterized by muscle atonia (i.e., functional paralysis of skeletal muscles, except for those controlling eye movement), studies have shown that people do exhibit affective facial expressions during sleep. Yet, these expressions are not necessarily tied to affective dream experiences, at least not in healthy participants (Clé et al., 2019;Maranci et al., 2021;Rivera-García et al., 2019). With regard to physiological responses, whereas some studies have reported associations between dream affect and autonomic activation during REM (e.g., Hauri and Castle, 1973;Paul et al., 2019), evidence for these associations is weak (Nielsen & Zadra, 2011;Schredl, 2018). ...
Affective scientists traditionally have focused on periods of active wakefulness when people are responding to external stimuli or engaging in specific tasks. However, we live much of our lives immersed in experiences not related to the current environment or tasks at hand—mind-wandering (or daydreaming) during wakefulness and dreaming during sleep. Despite being disconnected from the immediate environment, our brains still generate affect during such periods. Yet, research on stimulus-independent affect has remained largely separate from affective science. Here, we suggest that one key future direction for affective science will be to expand our field of view by integrating the wealth of findings from research on mind-wandering, sleep, and dreaming to provide a more comprehensive account of affect across the wake-sleep cycle. In developing our argument, we address two key issues: affect variation across the wake-sleep cycle, and the benefits of expanding the study of affect across the full wake-sleep cycle. In considering these issues, we highlight the methodological and clinical implications for affective science.
... A better understanding of the correlates of dream feelings may allow to conduct such assessments in the future. For instance, recent studies have shown that fear in dreams and nightmares has autonomic (Paul et al., 2019) and neurological (Sterpenich et al., 2020) correlates and that positive dream feelings may be manifested in the form of dream enacting behaviors (Rivera-García et al., 2019). ...
This article presents the feeling priming theory (FPT) of dreaming. According to the FPT, dreaming favors the motivation to avoid aversive anticipated events and to approach gratifying anticipated events. It is suggested that one component of anticipated emotions—anticipated feelings—is reproduced in dreams. Upon awakening and during the day, these anticipated feelings would remain activated (primed) in memory. Consequently, anticipated emotions would exert a greater influence on avoidance and approach behaviors, mainly through an increase in the intensity of anticipatory feelings (i.e., feelings of fear or hope/desire). This article comprises five main sections. First, the need for a new theory of the function of dreaming is addressed. Second, key constructs of the theory are described, including the constructs of “emotion” and “feeling.” Third, a brief overview of the theory is presented. Fourth, seven hypotheses that constitute the core of the theory are discussed along with supporting evidence. Fifth, an explanation of nightmares based on the proposed theory is offered. The FPT represents an alternative to theories that attribute an emotion regulation function to dreaming. It offers a new perspective on the relationship between dreaming and waking emotions. In particular, the FPT does not label nightmares as dysfunctional. Instead, nightmares and other dysphoric dreams are hypothesized to result from the same processes as normal dreaming.
... We all know, for example, that motor activity is inhibited during REM sleep. However, a study of the activity of the facial mimetic musculature during REM sleep showed that zygomaticus contractions were predictive of the experience of high positive emotions in women 114 . Thus, we have learned that women can smile even when dreaming. ...
Objective:
The aim of this study was to review the available findings on sex-related differences for sleep disorders, dreams and nightmares.
Materials and methods:
We explored the PubMed, EMBASE and Google Scholar electronic databases, with regards to the searching terms 'sleep', 'dreams', and 'nightmares' associated with 'sex' and/or 'gender'. Moreover, other supplementary terms for the searching strategy were 'chronobiology', and 'circadian rhythm'. Due to the relative paucity of studies including separate analysis by sex, and especially to their wide heterogeneity, we decided to proceed with a narrative review, highlighting the sex-related findings of each topic into apposite boxes.
Results:
On one hand, sleep disorders seem to be more frequent in women. On the other hand, sex-related differences exist for either dreams or nightmares. As for the former, differences make reference to dream content (men: physical aggression, women family themes), self-reported perspective (men dream in third person, women in first person), dream sharing (more frequent in women), lucid dreaming (women more realistic, men more controlled), and daydreaming (young men more frequently have sexual themes). Nightmares are more frequent in women too, and they are often associated with sleep disorders and even with psychiatric disorders, such as depression and/or anxiety. In women, a strong association has been shown between nightmares and evening circadian preference.
Conclusions:
For many years, and for many reasons, laboratory experiments have been conducted mainly, if not exclusively, on male animals. Thus, a novel effort towards a new governance of scientific and research activities with a gender-specific perspective has been claimed for all areas of medicine, and more research on sex-differences is strongly needed also on this topic.
... The prototype can also detect emotional expression via facial EMG and we previously demonstrated a system for recording the emotion of a VR user to an avatar, by mapping the user's facial expression during a VR experience to a 3d rigged model avatar. This presents a possibility for recording emotional expressions and displaying them on a dream avatar, since prior research has demonstrated that frowning and smiling muscle tension during sleep corresponds with dreamed emotional content (Perlis, 1991;Rivera-García et al., 2019) ...
We explore the application of a wide range of sensory stimulation technologies to the area of sleep and dream engineering. We begin by emphasizing the causal role of the body in dream generation, and describe a circuitry between the sleeping body and the dreaming mind. We suggest that nearly any sensory stimuli has potential for modulating experience in sleep. Considering other areas that might afford tools for engineering sensory content in simulated worlds, we turn to Virtual Reality (VR). We outline a collection of relevant VR technologies, including devices engineered to stimulate haptic, temperature, vestibular, olfactory, and auditory sensations. We believe these technologies, which have been developed for high mobility and low cost, can be translated to the field of dream engineering. We close by discussing possible future directions in this field and the ethics of a world in which targeted dream direction and sleep manipulation are feasible.
Dreams have long captivated human curiosity, but empirical research in this area has faced significant methodological challenges. Recent interdisciplinary advances have now opened up new opportunities for studying dreams. This review synthesizes these advances into three methodological frameworks and describes how they overcome historical barriers in dream research. First, with observable dreaming, neural decoding and real-time reporting offer more direct measures of dream content. Second, with dream engineering, targeted stimulation and lucidity provide routes to experimentally manipulate dream content. Third, with computational dream analysis, the generation and exploration of large dream-report databases offer powerful avenues to identify patterns in dream content. By enabling researchers to systematically observe, engineer, and analyze dreams, these innovations herald a new era in dream science.
There’s no need to introduce the first speaker of this morning as he is, arguably, one of the most renowned semioticians in the world. During his brilliant career he has published extensively on the topic of virtual realities and he will present to us his latest research on the defining technology of our times: the Simulatron. Specifically, he will focus on the 2053 incident which took place inside the virtual world of SimuLife during which all the users lost the ability to use verbal language and thus inventively resorted to different semiotic forms of meaning-making to communicate and interact. A topic which is of extreme relevance for this 2062 World congress « Semiotics in the Metalife ». So, without further ado, I welcome and leave the floor to Professor Wright..
Several studies have tried to identify the neurobiological bases of dream experiences, nevertheless some questions are still at the centre of the debate. Here, we summarise the main open issues concerning the neuroscientific study of dreaming. After overcoming the rapid eye movement (REM) ‐ non‐REM (NREM) sleep dichotomy, investigations have focussed on the specific functional or structural brain features predicting dream experience. On the one hand, some results underlined that specific trait‐like factors are associated with higher dream recall frequency. On the other hand, the electrophysiological milieu preceding dream report upon awakening is a crucial state‐like factor influencing the subsequent recall. Furthermore, dreaming is strictly related to waking experiences. Based on the continuity hypothesis, some findings reveal that dreaming could be modulated through visual, olfactory, or somatosensory stimulations. Also, it should be considered that the indirect access to dreaming remains an intrinsic limitation. Recent findings have revealed a greater concordance between parasomnia‐like events and dream contents. This means that parasomnia episodes might be an expression of the ongoing mental sleep activity and could represent a viable direct access to dream experience. Finally, we provide a picture on nightmares and emphasise the possible role of oneiric activity in psychotherapy. Overall, further efforts in dream science are needed (a) to develop a uniform protocol to study dream experience, (b) to introduce and integrate advanced techniques to better understand whether dreaming can be manipulated, (c) to clarify the relationship between parasomnia events and dreaming, and (d) to determine the clinical valence of dreams.
Though better knowledge concerning alexithymia in childhood could improve understanding of its development during the lifespan, it has been scarcely investigated in children. A necessary step in research on alexithymia is to create instruments for assessing the construct. The object of the present study was to develop an Italian Alexithymia Questionnaire for Children based on the instrument proposed by Rieffe et al. (2006) and to examine its factor structure and reliability. The English version of the questionnaire was translated into Italian and it was administered to 576 children recruited from primary and secondary schools (age mean = 10.78, s.d. = 1.67; males 357 and 219 females). Exploratory Factor Analysis (EFA) revealed preliminary evidence of a four-factor structure, which explained 37.90% of the variance: Factor 1 "Difficulty Describing Feelings", Factor 2 "Difficulty Identifying Feelings", Factor 3 "Confusion on Physical Sensations" and Factor 4 "Externally-Oriented Thinking". As to reliability, the Cronbach alpha indicated adequate internal consistency. Pearson correlations among the total score and the four factors were statistically significant. Moreover, the sample was divided into two groups (children and pre-adolescents) and a ttest was conducted: children showed significantly higher scores than adolescents on the total score of the questionnaire. No significant gender differences in mean total scores were found.
Key words: alexithymia, childhood, questionnaire, Italian version
Parole chiave: alessitimia, etŕ evolutiva, questionario, versione italiana
Negative facial expressions and frowns have been studied (albeit more rarely than smiles) in fetus’ and neonate’ sleep, but they have not been investigated during adult sleep. Video polysomnography (including corrugator muscle electromyography and face‐focussed video) was used to study negative facial expressions in sleeping adults, including healthy subjects and patients with/out parasomnia. Frowns were observed during sleep in 89/91 (97.8%) adults during normal (29 healthy subjects) and abnormal sleep (29 patients without parasomnia, 15 patients with disorders of arousal and 18 patients with rapid eye movement [REM] sleep behaviour disorder [RBD]). In healthy subjects, the following events occurred in decreasing frequency: isometric corrugator activations, brief frowns, and then prolonged frowns and raised eyebrows (both similarly rare). Frowns predominated in REM sleep, and had a lower frequency in non‐REM sleep. In healthy subjects, frowns were elementary and not associated with other face movements to the point of composing negative expressions. In contrast, frowns were occasionally associated with overt negative facial expressions in REM sleep in patients with RBD and a young patient with night terrors. They included mostly painful expressions and rarely sadness and anger in connection with apparently negative behaviours (shouts, painful moaning, and speeches). Frowns persist during normal sleep (mostly in REM sleep) in adults, but overt negative facial expressions are restricted to patients with parasomnia. Whether elementary frowns translate a negative dream emotion should be determined, but overt negative facial expressions during RBD could be used as a direct access to dream emotions.
The multitude of terms associated with love has given rise to a false perception of love. In this paper, only maternal and romantic love are considered. Love is usually regarded as a feeling, motivation, addiction, passion, and, above all, an emotion. This confusion has consequences in the lives of human beings, leading not only to divorces, suicides, femicides but possibly also to a number of mental illnesses and suffering. Therefore, it is crucial to first clarify what is meant by emotion, motivation and love. This work aims to finally place love within the category of physiological motivations, such as hunger, thirst, sleep, or sex, on the basis that love is also essential for human survival, especially in childhood. Love is presented from an evolutionary perspective.
Some other similarities between love and other physiological motivations are pointed out, such as its importance for appropriate human development, both its ontogeny and its permanence, and the long-lasting consequences of abuse and neglect. There are summarized reasons that account for this, such as the fact that physiological motivations are essential for survival and that love is an essential motivation for the survival of human offspring. Other reasons are that minimum changes in the quantity and quality of love alters development, that there can be a variety of neurophysiological and behavioural states within a motivation, and that motivations (also love) appear and change throughout development. Also, motivations and love sometimes may lead to an addictive behaviour. Finally, it is recognized that once physiological motivations (and love) appear, they become permanent.
In a third section, some potential social, cultural, clinical and scientific consequences of the proposed consideration of love as a motivation are discussed. Accordingly, love’s recognition as a motivation in the clinical field would imply a better understanding of its disorders and its inclusion in classifications manuals such as The Diagnostic and Statistical Manual of Mental Disorders (DSM), or in the International Classification of Diseases (ICD). Considering love as a motivation rather than an emotion could also impact the results of scientific research (an example is included).
A comprehensive understanding of these questions could potentially allow for a new therapeutic approach in the treatment of mental illness, while offering an all-inclusive evolutionary explanation of cultural phenomena such as the origin and diffusion of both language and art. Love should be understood as a physiological motivation, like hunger, sleep or sex, and not as an emotion as it is commonly considered.
Facial mimicry is the spontaneous response to others' facial expressions by mirroring or matching the interaction partner. Recent evidence suggested that mimicry may not be only an automatic reaction but could be dependent on many factors, including social context, type of task in which the participant is engaged, or stimulus properties (dynamic vs static presentation). In the present study, we investigated the impact of dynamic facial expression and sex differences on facial mimicry and judgment of emotional intensity. Electromyography recordings were recorded from the corrugator supercilii, zygomaticus major, and orbicularis oculi muscles during passive observation of static and dynamic images of happiness and anger. The ratings of the emotional intensity of facial expressions were also analysed. As predicted, dynamic expressions were rated as more intense than static ones. Compared to static images, dynamic displays of happiness also evoked stronger activity in the zygomaticus major and orbicularis oculi, suggesting that subjects experienced positive emotion. No muscles showed mimicry activity in response to angry faces. Moreover, we found that women exhibited greater zygomaticus major muscle activity in response to dynamic happiness stimuli than static stimuli. Our data support the hypothesis that people mimic positive emotions and confirm the importance of dynamic stimuli in some emotional processing.
Twenty participants hand-wrote reports of their dreams and waking life events and used an extensive lexicon of emotion words and types to rate the emotions experienced in each scene of each report. From these ratings, the incidence and intensity of 22 different emotion types in the two kinds of report were assessed. The incidence of emotion categories specified by a cognitive model of emotions was also assessed. Emotions were found to be present in virtually all scenes of all dream reports and only one of the 22 emotion types was never used in the ratings. The incidence of most of the emotion types was similar to that of reports of important life events. There was also evidence that the incidence of positive emotions was lower in dream reports than event reports, while the incidence of fear was higher. Specifically, the mean number of positive emotions per scene was lower and the proportion of fear was higher in dream reports than in event reports.
The lateral paragigantocellular nucleus (LPGi) is located in the ventrolateral medulla and is known as a sympathoexcitatory area involved in the control of blood pressure. In recent experiments, we showed that the LPGi contains a large number of neurons activated during PS hypersomnia following a selective deprivation. Among these neurons, more than two-thirds are GABAergic and more than one fourth send efferent fibers to the wake-active locus coeruleus nucleus. To get more insight into the role of the LPGi in PS regulation, we combined an electrophysiological and anatomical approach in the rat, using extracellular recordings in the head-restrained model and injections of tracers followed by the immunohistochemical detection of Fos in control, PS-deprived and PS-recovery animals. With the head-restrained preparation, we showed that the LPGi contains neurons specifically active during PS (PS-On neurons), neurons inactive during PS (PS-Off neurons) and neurons indifferent to the sleep-waking cycle. After injection of CTb in the facial nucleus, the neurons of which are hyperpolarized during PS, the largest population of Fos/CTb neurons visualized in the medulla in the PS-recovery condition was observed in the LPGi. After injection of CTb in the LPGi itself and PS-recovery, the nucleus containing the highest number of Fos/CTb neurons, moreover bilaterally, was the sublaterodorsal nucleus (SLD). The SLD is known as the pontine executive PS area and triggers PS through glutamatergic neurons. We propose that, during PS, the LPGi is strongly excited by the SLD and hyperpolarizes the motoneurons of the facial nucleus in addition to local and locus coeruleus PS-Off neurons, and by this means contributes to PS genesis.
Facial muscle contractions (FMC) are a commonly observed feature during sleep stages in human subjects. Previous studies have associated FMC to emotional expression during waking. Phasic features of rapid eye movement (REM) sleep, such as REMs have also been linked to an increase in limbic structure activity with a subsequent relation to emotional dream content. We hypothesized that FMC would be more frequent during REM sleep, and that FMC would correlate with the characteristic REMs of this sleep stage. The present study was designed to evaluate the density per minute of the phasic and sustained FMC of five facial muscles (frontalis, corrugator, orbicularis oculi, zygomatic major left and right) during all sleep stages, and to explore their relation with REMs density in six healthy participants during an 8 h sleep recording. Results showed a significant increase in FMC of all recorded muscles during REM sleep, both in frequency and duration. Additionally, as expected, during REM sleep there was a positive correlation among the facial muscles and between these and REMs. Nevertheless, although associated in number, both features (FMC and REMs) were never simultaneous. Our results suggest that limbic activation during REM sleep may be responsible for the enhancement of facial muscle activity, which may be consistent with the theoretical perspective of a higher emotional activity during REM sleep.
Determine the prevalence and gender distributions of behaviors enacted during dreaming ("dream-enacting [DE] behaviors") in a normal population; the independence of such behaviors from other parasomnias; and the influence of different question wordings, socially desirable responding and personality on prevalence.
3-group questionnaire study.
University classrooms
Three undergraduate samples (Ns = 443, 201, 496; mean ages = 19.9 +/- 3.2 y; 20.1 +/- 3.4 y; 19.1 +/- 1.6 y).
N/A.
Subjects completed questionnaires about DE behaviors and Social Desirability. Study 1 employed a nonspecific question about the behaviors, Study 2 employed the same question with examples, and Study 3 employed 7 questions describing specific behavior subtypes (speaking, crying, smiling/laughing, fear, anger, movement, sexual arousal). Somnambulism, somniloquy, nightmares, dream recall, alexithymia, and absorption were also assessed. Factor analyses were conducted to determine relationships among DE behaviors and their independence from other parasomnias. Prevalence increased with increasing question specificity (35.9%, 76.7%, and 98.2% for the 3 samples). No gender difference obtained for the nonspecific question, but robust differences occurred for more specific questions. Females reported more speaking, crying, fear and smiling/laughing than did males; males reported more sexual arousal. When controlling other parasomnias and dream recall frequency, these differences persisted. Factor solutions revealed that DE behaviors were independent of other parasomnias and of dream recall frequency, except for an association between dream-talking and somniloquy. Sexual arousal was related only to age. Behaviors were independent of alexithymia but moderately related to absorption.
Dream-enacting behaviors are prevalent in healthy subjects and sensitive to question wording but not social desirability. Subtypes are related, differ with gender and occur independently of other parasomnias.
This paper addresses the correlation of dreamed and actual actions. This issue is related to the theory of neural simulation of action. The simulation theory postulates that, in general, covert actions are actual actions relying on the same brain regions, except for the fact that they are not executed. By reviewing studies conducted in the field of dream and lucid dream research on REM sleep it will be shown that correlations between dreamed and actual actions can be found for central nervous activity, autonomic responses and time aspects. Recent findings from research on lucid dreaming and motor learning further support the notion that actions in dreams are represented on higher cognitive levels - equivalent to actual movements - and therefore share, to some extent, the same central structures. The reviewed findings will be discussed and future directions will be given.
Cognitive neuroscience continues to build meaningful connections between affective behavior and human brain function. Within the biological sciences, a similar renaissance has taken place, focusing on the role of sleep in various neurocognitive processes and, most recently, on the interaction between sleep and emotional regulation. This review surveys an array of diverse findings across basic and clinical research domains, resulting in a convergent view of sleep-dependent emotional brain processing. On the basis of the unique neurobiology of sleep, the authors outline a model describing the overnight modulation of affective neural systems and the (re)processing of recent emotional experiences, both of which appear to redress the appropriate next-day reactivity of limbic and associated autonomic networks. Furthermore, a rapid eye movement (REM) sleep hypothesis of emotional-memory processing is proposed, the implications of which may provide brain-based insights into the association between sleep abnormalities and the initiation and maintenance of mood disturbances.
There are two distinct approaches in the modeling and classification of human emotions. One is the identification of the fundamental variables or dimensions of the affective system, and the other is the recognition of primary emotions by the analysis of universal facial expressions. In this paper a system of classification of the human affective system is proposed which integrates the foundations of both approaches using a method derived from the Munsell color system. The resulting architecture is a topological model based upon a methodic, constructive and progressively empirical analysis of the emotional vocabulary in Spanish. Since the words used to designate particular emotions in natural languages seek to express discrete affective states and effectively serve as communication devices among individuals, we ascertain that the identification of such words and their mutual meaning relationships constitutes a valid route to understand the structure of the affective system. The exercise consists of six consecutive stages: 1) The compilation of a vocabulary of words in Spanish which designate particular emotions (n=328); 2) The grouping of these terms in 28 clusters or semantic fields of 6 to 17 related ideas (mean = 12); 3) The selection of a representative term for each cluster or set of kindred words; 4) The ordering of the words within each set in a sequence according to the intensity of the designed emotion; 5) The identification of pairs of antonymous sets (pleasant and unpleasant) and, thereby, the establishment of 14 bipolar axis of human emotion (calm-tension, certainty-uncertainty, compassion-anger, fun-boredom, pleasantnessunpleasantness, happiness-sadness, pleasure-pain, satisfaction-frustration, desirereject, love-hate, courage-fear, strength-tiredness, enthusiasm-aparthy, arrogancehumiliation); 6) The elaboration of the final model of the human affective system as an circle or wheel where the 14 axis are located in reference to an orthogonal two-dimensional sys
Physiological measures have traditionally been viewed in social psychology as useful only in assessing general arousal and therefore as incapable of distinguishing between positive and negative affective states. This view is challenged in the present report. Sixteen subjects in a pilot study were exposed briefly to slides and tones that were mildly to moderately evocative of positive and negative affect. Facial electromyographic (EMG) activity differentiated both the valence and intensity of the affective reaction. Moreover, independent judges were unable to determine from viewing videotapes of the subjects' facial displays whether a positive or negative stimulus had been presented or whether a mildly or moderately intense stimulus had been presented. In the full experiment, 28 subjects briefly viewed slides of scenes that were mildly to moderately evocative of positive and negative affect. Again, EMG activity over the brow (corrugator supercilia), eye (orbicularis oculi), and cheek (zygomatic major) muscle regions differentiated the pleasantness and intensity of individuals' affective reactions to the visual stimuli even though visual inspection of the videotapes again indicated that expressions of emotion were not apparent. These results suggest that gradients of EMG activity over the muscles of facial expression can provide objective and continuous probes of affective processes that are too subtle or fleeting to evoke expressions observable under normal conditions of social interaction.
The corticobulbar projection to musculotopically defined subsectors of the facial nucleus was studied from the face representation of the primary (M1), supplementary (M2), rostral cingulate (M3), caudal cingulate (M4) and ventral lateral pre- (LPMCv) motor cortices in the rhesus monkey. We also investigated the corticofacial projection from the face/arm transitional region of the dorsal lateral premotor cortex (LPMCd). The corticobulbar projection was defined by injecting anterograde tracers into the face representation of each motor cortex. In the same animals, the musculotopic organization of the facial nucleus was defined by injecting fluorescent retrograde tracers into individual muscles of the upper and lower face. The facial nucleus received input from all face representations. M1 and LPMCv gave rise to the heaviest projection with progressively diminished intensity occurring in the M2, M3, M4 and LPMCd projections, respectively. Injections in all cortical face representations labelled terminals in all nuclear subdivisions (dorsal, intermediate, medial and lateral). However, significant differences occurred in the proportion of labelled boutons found within each functionally characterized subdivision. M1, LPMCv, LPMCd and M4 projected primarily to the contralateral lateral subnucleus, which innervated the perioral musculature. M2 projected bilaterally to the medial subnucleus, which supplied the auricular musculature. M3 projected bilaterally to the dorsal and intermediate subnuclei, which innervated the frontalis and orbicularis oculi muscles, respectively. Our results indicate that the various cortical face representations may mediate different elements of facial expression. Corticofacial afferents from M1, M4, LPMCv and LPMCd innervate primarily the contralateral lower facial muscles. Bilateral innervation of the upper face is supplied by M2 and M3. The widespread origin of these projections indicates selective vulnerability of corticofacial control following subtotal brain injury. The finding that all face representations innervate all nuclear subdivisions, to some degree, suggests that each motor area may participate in motor recovery in the event that one or more of these motor areas are spared following subtotal brain injury. Finally, the fact that a component of the corticofacial projection innervating both upper and lower facial musculature arises from the limbic proisocortices (M3 and M4) and frontal isocortices (M1, M2, LPMCv and LPMCd) suggests a potential anatomical substrate that may contribute to the clinical dissociation of emotional and volitional facial movement.
No consensus has been reached on the characteristics of emotional experience during rapid eye movement sleep (REM). Thus, the relationship between the emotional brain activation and mental activity in REM remains unclear. Our objective is to characterize emotional experience in REM in order to facilitate understanding of brain-mind correlations in this state.
We combined instrumental awakenings from REM with the subjects' own ratings of the occurrence and intensity of discrete emotion types for each line in their REM mentation reports.
The study was performed in the subjects' own homes over three consecutive nights using ambulatory polysomnography.
Nine normal healthy subjects, age 31-60 (mean=43.0).
Awakenings 5-15 minutes into REM periods across the night.
Emotions were found in 74% of 88 mentation reports, with a balanced proportion of positive and negative emotions. Among the reports scored for emotions, 14% contained one emotion and 86% contained two or more different emotion types. Joy/elation was the most frequent emotion, found in 36% of the reports, followed by surprise (24%), anger (17%), anxiety/fear (11%), and sadness (10%). Anxiety/fear was significantly less intense than joy/elation, anger, and surprise. Except for surprise, no specific emotion type changed from the first to the second half of the night. Negative emotions and surprise but not positive emotions varied significantly across subjects.
The analysis of subject reports of emotions following instrumental awakenings demonstrate a balanced and widespread occurrence of both positive and negative emotions in REM sleep dreams. Emotions in REM are likely to be powerfully modulated by the neurobiological processes which differentiate REM from waking.
1 I. INTRODUCTION 2 A. An Integrative Strategy 2 B. A State Space Model of the Brain-Mind 3 C. Caveat Lector 4 II. THE PHENOMENOLOGY AND PSYCHOPHYSIOLOGY OF WAKING, SLEEPING AND DREAMING 5 DREAMING and the BRAIN: Toward a Cognitive Neuroscience of Conscious States http://home.earthlink.net/~sleeplab/bbs/BBS.html (1 of 222) [1/6/2000 2:48:02 PM] A. Early findings of distinct differences between REM and NREM mentation 6 B. Overview of the NREM-REM Sleep Mentation Controversy 12 1. REM Sleep Dreaming is not Qualitatively Unique 13 2. The Relationship Between Dream Features and Dream Report Length 17 C. Methodological Considerations in the Study of Dreaming 21 1. The Reduction of Psychological States to Narrative Reports 21 2. The Sleep Laboratory Environment 26 3. The Question of "Similarity" and "Difference" 29 4. The Source and Fate of Dream Memory 33 5. Type I vs. Type II Statistical Analyses 39 6. The Need for New Approaches 40 III. THE COGNITIVE NEUROSCIENCE OF WAKING, SLEEPING AN...
Previous findings of heightened covert oral behavior during linguistic activities suggested that increases in covert oral behavior might also occur during conversational dreams. It was found that covert oral behavior (lip and chin electromyograms) was significantly higher during rapid eye movement (REM) periods in which there were conversational dreams than during nonrapid eye movement (NREM) periods. On the other hand, REM periods for the visual dreams showed only minor and nonsignificant changes in covert oral behavior, relative to the NREM periods. Little change occurred for neck responses, suggesting that behavioral changes were localized in the speech region. These findings are thus consistent with those obtained from waking Ss—covert oral behavior may serve a linguistic function during dreams too.
During dreaming, as well as during wakefulness, elaborative encoding, indexing and ancient art of memory (AAOM) techniques, such as the method of loci, may coincide with emotion regulation. These techniques shed light on the link between dreaming and emotional catharsis, post-traumatic stress disorder, supermemorization during sleep as opposed to wakefulness, and the developmental role of rapid eye movement (REM) sleep in children.
Investigated the emotional profile of dreams and the relationship between dream emotion and cognition using a form that specifically asked Ss to identify emotions within their dreams. 200 dream reports were collected from 14 female and 6 male university students. Anxiety/fear was reported most frequently, followed by joy/elation, anger, sadness, shame/guilt, and, least frequently, affection/eroticism. Unexpectedly, there was no significant gender difference in the profiles of emotion reported. A significant correlation was found between the occurrence of bizarreness and major shifts in emotion. Results support the conclusion that dreaming is a mental state whose general emotional features are widely shared across individuals and are strongly linked to cognitive features within individual dreams. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Recently, we proposed that the coupling of cognitive activation and diminished arousal during REM sleep may have a mood regulating effect. Conversely, increased arousal during REM sleep may be associated with mood dysregulation. In this paper, the desensitization model is described, and data are presented on the association between motor activity during REM sleep, wakefulness and severity of depression. Motor activity sleep EEG data and two measures of depressive severity (BDI and HRSD) were obtained from 23 depressed patients. BDI scores were significantly correlated with motor activity only during REM sleep. HRSD scores were correlated with motor activity only during quiet wakefulness. These findings are consistent with the theoretical perspective that dysregulation in arousal mechanisms during REM sleep may promote mood disturbance during the depressive episode.
Dreams are a remarkable experiment in psychology and neuroscience, conducted every night in every sleeping person. They show that the human brain, disconnected from the environment, can generate an entire world of conscious experiences by itself. Content analysis and developmental studies have promoted understanding of dream phenomenology. In parallel, brain lesion studies, functional imaging and neurophysiology have advanced current knowledge of the neural basis of dreaming. It is now possible to start integrating these two strands of research to address fundamental questions that dreams pose for cognitive neuroscience: how conscious experiences in sleep relate to underlying brain activity; why the dreamer is largely disconnected from the environment; and whether dreaming is more closely related to mental imagery or to perception.
A consensual, componential model of emotions conceptualises them as experiential, physiological, and behavioural responses to personally meaningful stimuli. The present review examines this model in terms of whether different types of emotion-evocative stimuli are associated with discrete and invariant patterns of responding in each response system, how such responses are structured, and if such responses converge across different response systems. Across response systems, the bulk of the available evidence favours the idea that measures of emotional responding reflect dimensions rather than discrete states. In addition, experiential, physiological, and behavioural response systems are associated with unique sources of variance, which in turn limits the magnitude of convergence across measures. Accordingly, the authors suggest that there is no "gold standard" measure of emotional responding. Rather, experiential, physiological, and behavioural measures are all relevant to understanding emotion and cannot be assumed to be interchangeable.
Rapid eye movement (REM) sleep and dreaming may be implicated in cross-night adaptation to emotionally negative events. To evaluate the impact of REM sleep deprivation (REMD) and the presence of dream emotions on a possible emotional adaptation (EA) function, 35 healthy subjects randomly assigned to REMD (n = 17; mean age 26.4 +/- 4.3 years) and control (n = 18; mean age 23.7 +/- 4.4 years) groups underwent a partial REMD and control nights in the laboratory, respectively. In the evening preceding and morning following REMD, subjects rated neutral and negative pictures on scales of valence and arousal and EA scores were calculated. Subjects also rated dream emotions using the same scales and a 10-item emotions list. REMD was relatively successful in decreasing REM% on the experimental night, although a mean split procedure was applied to better differentiate subjects high and low in REM%. High and low groups differed - but in a direction contrary to expectations. Subjects high in REMD% showed greater adaptation to negative pictures on arousal ratings than did those low in REMD% (P < 0.05), even after statistically controlling sleep efficiency and awakening times. Subjects above the median on EA(valence) had less intense overall dream negativity (P < 0.005) and dream sadness (P < 0.004) than subjects below the median. A correlation between the emotional intensities of the morning dream and the morning picture ratings supports a possible emotional carry-over effect. REM sleep may enhance morning reactivity to negative emotional stimuli. Further, REM sleep and dreaming may be implicated in different dimensions of cross-night adaptation to negative emotions.
Ten adult subjects, selected for good dream recall and ability to produce spontaneously fine limb movements in the laboratory, reported their last dream experience after awakenings from REM sleep during various limb movement and no movement conditions. The reports were rated for amount and girdle location of dreamed actions by judges blind to the awakening condition. There was a significant correlation between the number of girdles moving before awakening and the amount of dreamed action. Also, when dreams from single girdle movement awakening conditions were examined, the girdle active before awakening was dreamed as moving to a significant degree.
The clinical and research literature suggests that waking dream reflection increases awareness of feelings. To examine this possibility, 16 male and 16 female participants spent a single night in the sleep laboratory while rapid eye movement (REM) sleep physiology and facial electromyogram (EMG) were monitored. Participants in the dream imagery condition were awakened from REM sleep and asked to reflect on their dreams. Participants in the fantasy imagery condition were awakened from REM sleep and asked to reflect on guided fantasies modeled on dream narratives. Participants were asked to reflect either on the affective connotations of their imagery or on the cognitive aspects of their imagery. Unexpectedly, self-reported awareness of feelings was less common during either affective or cognitive reflection on dreams than during such reflection on fantasies, especially for females. Also, kinesthetic sensitivity, as indicated by Rorschach movement responses, was less after dream reflection than after reflection on fantasy imagery, again especially for females. In contrast, facial EMG activity was greater during dream reflection than during fantasy reflection. Since facial EMG during REM sleep and during dream reflection was correlated with self-reported orienting within dream imagery, these results are understandable as evidence for the "carry-over" of REM orienting activity during dream reflection, resulting in reduced affective/kinesthetic sensitivity and reduced awareness of feelings.
Polygraphic recordings were made in 20 normal adult female subjects and a total of 45 sleep records were obtained. Subjects were awakened in Stage REM or Stage 2 and, when they recalled dreaming, they were asked whether or not they had been speaking in their dreams. Polygraphic recordings enabled determination of the presence or absence of phasic EMG discharges in speech and nonspeech muscles (mimic muscle and extremity muscles) just prior to awakenings. Results were examined for correlation with presence or absence of speech recall by the subjects.
When phasic discharges occurred in speech muscles during either Stage REM or Stage 2, recall of speech in dreams was prevalent, while such recall was not observed when discharges occurred in nonspeech muscles. Moreover, recall of speech in dreams was rarely observed when no muscle phasic discharges occurred.
These results suggest that speech in dreams may be accompanied by phasic discharges of speech muscles.
We analyzed the electrical activity of the basolateral amygdala (BLA), anterior and posterior regions of the cingulate gyrus (A-CG and P-CG), the dorsal hippocampus (DH), the anterior ventral thalamic nucleus (AVTN), and the sensory motor cortex during the rapid eye movements and ponto-geniculo-occipital (PGO) activity of REM sleep in cats in chronic preparation. Polygraphic recordings and computational perievent averages using the phasic contractions of the lateral rectus muscle (LR) of the eyeball as the triggering signal of the analysis were performed. We observed biphasic potentials (200-300 ms) of variable amplitude, related to the phasic phenomena of REM sleep, in the BLA, A-CG, P-CG, DH, and AVTN. The latencies of the potentials of these regions were always greater than those of the geniculate PGO activities. We propose that the recorded limbic potentials resulted from propagation of PGO activity and that this phenomenon may reflect the limbic structure of the hallucinatory, vegetative, and emotional components of REM sleep.
To test that REM sleep and/or dreaming aid in the overnight regulation of negative mood, 60 student subjects, selected to have no current or past episodes of depression, were tested with the Profile of Mood States (POMS) before and after two nights of laboratory sleep. There was a significant overnight effect of sleep on the Depression scale (Dep) both on a sleep-through night and a night of REM awakenings for dream recall. Pre-sleep Dep was significantly correlated with the affect in the first REM report. Although Dep scores were truncated due to the screening criteria, a subgroup of the 10 highest scorers differed from the 50 low scorers in the distribution of dream affect categories across the night. Low scorers displayed a flat distribution of positive and negative affect in dreams, while those with some pre-sleep depressed mood showed a pattern of decreasing negative and increasing positive affect in dreams reported from successive REM periods. This suggests that dreaming may actively moderate mood overnight in normal subjects.
Previous research on asymmetric effects of emotional expression and brain-hemispheric asymmetry has supported opposing theories of hemispheric dominance in the control of emotional reactions. In the present study, 32 subjects were exposed to pictures of happy and angry facial stimuli while facial electromyographic (EMG) activity from the zygomatic major and the corrugator supercilii muscle regions was detected from the left and right sides of the face. The subjects reacted spontaneously and rapidly with larger zygomatic EMG activity to happy facial stimuli and larger corrugator EMG activity to angry stimuli. These distinct reactions were significantly larger on the left side of the face. It is concluded that the present results support the hypothesis that the right brain hemisphere is predominantly involved in the control of spontaneously evoked emotional reactions.
Sleep researchers in different disciplines disagree about how fully dreaming can be explained in terms of brain physiology. Debate has focused on whether REM sleep dreaming is qualitatively different from nonREM (NREM) sleep and waking. A review of psychophysiological studies shows clear quantitative differences between REM and NREM mentation and between REM and waking mentation. Recent neuroimaging and neurophysiological studies also differentiate REM, NREM, and waking in features with phenomenological implications. Both evidence and theory suggest that there are isomorphisms between the phenomenology and the physiology of dreams. We present a three-dimensional model with specific examples from normally and abnormally changing conscious states.
Keywords:facial muscle;brainstem;emotional motor system;somatic motor system
The work of Kleitman and his students1-4 has demonstrated conclusively that a low-voltage, fast-activity electroencephalographic (EEG) pattern during sleep is typically associated with dreaming. By continuous monitoring of brain waves during sleep, it is now possible to localize the dream as it occurs. The discovery of the association of a specific EEG pattern with dreaming was antedated by the observation that rapid, conjugate eye movements during sleep are associated with visual dreams.1-3,5 Not all dreams are visual, however, and dreams without rapid eye movements (REM’s) have been observed to be nonvisual in nature. Indeed, the amount of reported physical activity by the dreamer has been found by Dement and Wolpert5 to be related to the amount of eye movement observed electrically, the EEG pattern being constant regardless of the amount of activity in the dream. In addition, the spatial direction of the
: Body movements were detected by means of highly sensitive semiconductor strain gauges on 10 subjects who slept overnight in a dream laboratory. Continuous measurement of movement from the eye, throat, hand, and foot indicated that activation was an integrated process which appears simultaneously from all locations. Correlations of level of eye movement activity and average activity level from other points measured ranged between .55 and .85 for each of 10 subjects, with the majority exceeding .75. Body movement patterns correctly identified 32 of 41 peaks of eye movement activity. Copyright (C) 1965 by American Psychosomatic Society
In this chapter, we aimed at further characterizing the functional neuroanatomy of the human rapid eye movement (REM) sleep at the population level. We carried out a meta-analysis of a large dataset of positron emission tomography (PET) scans acquired during wakefulness, slow wave sleep and REM sleep, and focused especially on the brain areas in which the activity diminishes during REM sleep. Results show that quiescent regions are confined to the inferior and middle frontal cortex and to the inferior parietal lobule. Providing a plausible explanation for some of the features of dream reports, these findings may help in refining the concepts, which try to account for human cognition during REM sleep. In particular, we discuss the significance of these results to explain the alteration in executive processes, episodic memory retrieval and self representation during REM sleep dreaming as well as the incorporation of external stimuli into the dream narrative.
36 subjects' facial electromyographic (EMG) activity at the zygomatic, corrugator, and levator labii (superioris/alaeque nasi) muscle regions were recorded while they were acting self-generated emotions of happiness, anger, fear, sadness, disgust, and surprise. Analysis showed that the EMG activity at the levator labii region generated significantly higher power than those at the corrugator region while acting out disgust, the EMG activity at the zygomatic region generated significantly higher power than those at corrugator region while acting out happiness and surprise, and the EMG activity at the corrugator region generated significantly higher power than those at zygomatic and levator labii regions while acting out anger, sadness, and fear. It was concluded that the negative self-generated emotions were associated with increased EMG activity of corrugator muscles and positive self-acting emotions with increased EMG activity of zygomatic muscles.
We recorded the magnetoencephalographic (MEG) signal from three subjects before, during and after eye movements cued to a tone, self-paced, awake and during rapid eye movement (REM) sleep. During sleep we recorded the MEG signal throughout the night together with electroencephalographic (EEG) and electromyographic (EMG) channels to construct a hypnogram. While awake, just prior to and during eye movements, the expected well time-locked physiological activations were imaged in pontine regions, with early 3 s priming. Activity in the frontal eye fields (FEF) was identified in the 300 ms before the saccade onset. Visual cortex activation occurred 200 ms after saccades. During REM, compared to the eyes closed awake condition, activity was higher in supplementary motor area (SMA) and lower in inferior parietal and precuneus cortex. Electro-occulographic (EOG) activity just prior to REM saccades correlated with bilateral pontine and FEF activity some 250-400 ms before REM saccade onset, which in turn was preceded 200 ms earlier by reciprocal activation of the pons and FEF. An orbitofrontal-amygdalo-parahippocampal-pontine sequence, possibly related to emotional activation during REM sleep, was identified in the last 100 ms leading to the REM saccade, but not linked to saccade initiation.
Emotionalität im Traum und EMG der Gesichtsmuskeln
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