The influential threat simulation theory asserts that dreaming yields adaptive advantage by providing a virtual environment in which threat-avoidance may be safely rehearsed. We have previously found the incidence of biologically threatening dreams to be around 20%, with successful threat avoidance occurring in approximately one-fifth of such dreams. TST asserts that threat avoidance is over-represented relative to other possible dream contents. To begin assessing this issue, we contrasted the incidence of ‘avoidance’ dreams with that of their opposite: ‘approach’ dreams. Because (...) TST states that the threat-avoidance function is only fully activated in ecologically valid contexts, we also performed this contrast for populations living in both high- and low-threat environments. We find that ‘approach’ dreams are significantly more prevalent across both contexts. We suggest these results are more consistent with the view that dreaming is generated by reward-seeking systems than by fear-conditioning systems, although reward-seeking is clearly not the only factor determining the content of dreams. (shrink)

Higher-Order Thought (HOT) theories of consciousness maintain that the kind of awareness necessary for phenomenal consciousness depends on the cognitive accessibility that underlies reporting. -/- There is empirical evidence strongly suggesting that the cognitive accessibility that underlies the ability to report visual experiences depends on the activity of the dorsolateral prefrontal cortex (dlPFC). This area, however, is highly deactivated during the conscious experiences we have during sleep: dreams. HOT theories are jeopardized, as I will argue. I will briefly present HOT (...) theories in the first section. Section 2 offers empirical evidence to the effect that the cognitive accessibility that underlies the ability to report depends on the dorsolateral prefrontal cortex: dlPFC is the neural correlate of HOTs. Section 3 shows the evidence we have of the deactivation of this brain area during dreams and, in section 4, I present my argument. Finally, I consider and rejoin two possible replies that my opponent can offer: the possibility of an alternative neural correlate of HOTs during dreams and the denial that we have phenomenally conscious experiences during sleep. (shrink)

Scientific study of dreams requires the most objective methods to reliably analyze dream content. In this context, artificial intelligence should prove useful for an automatic and non subjective scoring technique. Past research has utilized word search and emotional affiliation methods, to model and automatically match human judges’ scoring of dream report’s negative emotional tone. The current study added word associations to improve the model’s accuracy. Word associations were established using words’ frequency of co-occurrence with their defining words as found in (...) a dictionary and an encyclopedia. It was hypothesized that this addition would facilitate the machine learning model and improve its predictability beyond those of previous models. With a sample of 458 dreams, this model demonstrated an improvement in accuracy from 59% to 63% on the negative emotional tone scale, and for the first time reached an accuracy of 77% on the positive scale. (shrink)

Biological realism (Revonsuo, 2001, 2006) states that dreaming is a biological phenomenon and therefore explainable in naturalistic terms, similar to the explanation of other biological phenomena. In the biological sciences, the structure of explanations can be described with the help of a framework called 'multilevel explanation'. The multilevel model provides a context that assists to clarify what needs to be explained and how, and how to place different theories into the same model. Here, I will argue that the multilevel framework (...) would be useful when we try to construct scientific explanations of dreaming. (shrink)

Malcolm-Smith, Solms, Turnbull and Tredoux [Malcolm-Smith, S., Solms, M.,Turnbull, O., & Tredoux, C. . Threat in dreams: An adaptation? Consciousness and Cognition, 17, 1281–1291.] have made an attempt to test the Threat-Simulation Theory , a theory offering an evolutionary psychological explanation for the function of dreaming [Revonsuo, A. . The reinterpretation of dreams: An evolutionary hypothesis of the function of dreaming. Behavioral and Brain Sciences, 23, 877–901]. Malcolm-Smith et al. argue that empirical evidence from their own study as well as (...) from some other studies in the literature does not support the main predictions of the TST: that threatening events are frequent and overrepresented in dreams, that exposure to real threats activates the threat-simulation system, and that dream threats contain realistic rehearsals of threat avoidance responses. Other studies, including our own, have come up with results and conclusions that are in conflict with those of Malcolm-Smith et al. In this commentary, we provide an analysis of the sources of these disagreements, and their implications to the TST. Much of the disagreement seems to stem from differing interpretations of the theory and, consequently, of differing methods to test it. (shrink)

Revonsuo’s influential Threat Simulation Theory predicts that people exposed to survival threats will have more threat dreams, and evince enhanced responses to dream threats, compared to those living in relatively safe conditions. Participants in a high crime area differed significantly from participants in a low crime area in having greater recent exposure to a life-threatening event . Contrary to TST’s predictions, the SA participants reported significantly fewer threat dreams , and did not differ from the Welsh participants in responses to (...) dream threats . Overall, the incidence of threat in dreams was extremely low—less than 20% of dreams featured realistic survival threats. Escape from dream threats occurred in less than 2% of dreams. We conclude that this evidence contradicts key aspects of TST. (shrink)

The threat simulation theory of dreaming states that dream consciousness is essentially an ancient biological defence mechanism, evolutionarily selected for its capacity to repeatedly simulate threatening events. Threat simulation during dreaming rehearses the cognitive mechanisms required for efficient threat perception and threat avoidance, leading to increased probability of reproductive success during human evolution. One hypothesis drawn from TST is that real threatening events encountered by the individual during wakefulness should lead to an increased activation of the system, a threat simulation (...) response, and therefore, to an increased frequency and severity of threatening events in dreams. Consequently, children who live in an environment in which their physical and psychological well-being is constantly threatened should have a highly activated dream production and threat simulation system, whereas children living in a safe environment that is relatively free of such threat cues should have a weakly activated system. We tested this hypothesis by analysing the content of dream reports from severely traumatized and less traumatized Kurdish children and ordinary, non-traumatized Finnish children. Our results give support for most of the predictions drawn from TST. The severely traumatized children reported a significantly greater number of dreams and their dreams included a higher number of threatening dream events. The dream threats of traumatized children were also more severe in nature than the threats of less traumatized or non-traumatized children. (shrink)

Revonsuo proposed an intriguing and detailed evolutionary theory of dreams which stipulates that the biological function of dreaming is to simulate threatening events and to rehearse threat avoidance behaviors. The goal of the present study was to test this theory using a sample of 212 recurrent dreams that was scored using a slightly expanded version of the DreamThreat rating scale. Six of the eight hypotheses tested were supported. Among the positive findings, 66% of the recurrent dream reports contained one or (...) more threats, the threats tended to be dangerous and aimed at the dreamer, and when facing a threat, the dreamer tended to take defensive or evasive actions that were possible and reasonable. However, less than 15% of the recurrent dreams depicted realistic and probable situations critical for one’s physical survival or reproductive success and the dreamer rarely succeeded in fleeing the threat despite important and appropriate efforts. The findings thus provide mixed support for the threat simulation theory. (shrink)

Zadra, Desjardins, and Marcotte tested several predictions derived from the Threat Simulation Theory of dreaming in a large sample of recurrent dreams. In response to these findings, Valli and Revonsuo presented a commentary outlining alternate conceptualizations and explanations for the results obtained. We argue that many points raised by Valli and Revonsuo do not accurately reflect our main findings and at times present a biased assessment of the data. In this article, we provide necessary clarifications and responses to each one (...) of their main points of discussion. (shrink)

We tested the new threat simulation theory of the biological function of dreaming by analysing 592 dreams from 52 subjects with a rating scale developed for quantifying threatening events in dreams. The main predictions were that dreams contain more frequent and more severe threats than waking life does; that dream threats are realistic; and that they primarily threaten the Dream Self who tends to behave in a relevant defensive manner in response to them. These predictions were confirmed and the theory (...) empirically supported. We suggest that the threat simulation theory of dreaming may have wider implications for theories about the function of consciousness. (shrink)

Many mental phenomena involve thinking about people who do not exist. Imagined characters appear in planning, dreams, fantasizing, imaginary companions, bereavement hallucinations, auditory verbal hallucinations, and as characters created in fictional narratives by authors. Sometimes these imagined persons are felt to be completely under our control, as when one fantasizes about having a great time at a party. Other times, characters feel as though they are outside of our conscious control. Dream characters, for example, are experienced by dreamers as autonomous (...) entities, and often do things that frighten and surprise dreamers. Some imagined persons, such as characters in fiction, start off under conscious control of the author, but over time, can appear to gain an illusion of independent agency. I propose an explanation for different autonomy attributions: characters are by default non-autonomous, unless their personalities are well-practiced. Characters become autonomous because modeling their thinking has become automatized, like many other well-practiced activities. (shrink)

Is it ever wrong to cheat in a dream? It has been argued that the conjunction of reasonable claims about dreams with Evaluational Internalism (the view that moral evaluation is determined by factors ‘internal’ to agency, such as intentions) entails a positive answer. This implausible result seemingly provides reason to favour an alternative theory of moral evaluation. I here argue that a wide range of Evaluational Externalist views (which base moral evaluation on factors ‘external’ to agency, such as harms produced) (...) are similarly committed to morality in dreams. I end by identifying implications for theorising about dreams and morality. (shrink)

The experience of skilled action occurs in dreams if we take dream reports at face value. However, what these reports indicate requires nuanced analysis. It is uncertain what it means to perform any action in a dream whatsoever. If skilled actions do occur in dreams, this has important implications for both theory of action and theory of dreaming. Here, it is argued that since some dreams generate a convincing, hallucinated world where we have virtual bodies that interact with virtual objects, (...) there is a sense in which we can perform virtual actions. Further, we can also perform skilfully, although not all apparent skilful performance is as it seems. Since the dream world is generated by the dreamer’s own mind, it can be difficult to determine whether the dream world simply allows goals to be achieved without the abilities that would be required in a similar waking scenario. Because of this, individual dream reports alone are insufficient to determine what skills are demonstrated in a particular dream. However, taken with evidence from REM sleep behaviour disorder, incompetent dreams, lucid dreams and motor-skill practise, it is likely that skilled virtual dream performance at times involves both opportunity for virtual behaviour and the display of competence. Evidence from cognitive science suggests that dreamers can also lose competence through forgetting and other cognitive incapacities but, more surprisingly, it is possible to gain abilities in a robust sense, consistent with the idea that some dreams, at least, are virtual realities rather than imagination. (shrink)

Sleep and dreaming are important daily phenomena that are receiving growing attention from both the scientific and the philosophical communities. The increasingly popular predictive brain framework within cognitive science aims to give a full account of all aspects of cognition. The aim of this paper is to critically assess the theoretical advantages of Predictive Processing (PP, as proposed by Clark 2013, Clark 2016; and Hohwy 2013) in defining sleep and dreaming. After a brief introduction, we overview the state of the (...) art at the intersection between dream research and PP (with particular reference to Hobson and Friston 2012; Hobson et al. 2014). In the following sections we focus on two theoretically promising aspects of the research program. First, we consider the explanations of phenomenal consciousness during sleep (i.e. dreaming) and how it arises from the neural work of the brain. PP provides a good picture of the peculiarity of dreaming but it can’t fully address the problem of how consciousness comes to be in the first place. We propose that Integrated Information Theory (IIT) (Oizumi et al. 2014; Tononi et al. 2016) is a good candidate for this role and we will show its advantages and points of contact with PP. After introducing IIT, we deal with the evolutionary function of sleeping and dreaming. We illustrate that PP fits with contemporary researches on the important adaptive function of sleep and we discuss why IIT can account for sleep mentation (i.e. dreaming) in evolutionary terms (Albantakis et al. 2014). In the final section, we discuss two future avenues for dream research that can fruitfully adopt the perspective offered by PP: (a) the role of bodily predictions in the constitution of the sleeping brain activity and the dreaming experience, and (b) the precise role of the difference stages of sleep (REM (Rapid eye movement), NREM (Non-rapid eye movement) in the constitution and refinement of the predictive machinery. (shrink)

Keskityn siihen miten Leibnizilla yksittäiset mielihyvän tai mielipahan tiedostamattomat havainnot voivat kasautua tai tiivistyä ja muodostaa vähitellen tunteita, joista tulemme tietoisiksi.

Though there is much else in Levine's book that is also worthy of discussion, this critical study focuses exclusively on his central positive thesis that phenomenal consciousness exhibits two features that “both resist explanatory reduction to the physical: subjectivity and qualitative character” (p. 175).

Initial evidence suggests that suppressing a thought prior to sleep results in subsequent dreaming of that thought. The present research examined the influence of cognitive load on dreaming following suppression. In Experiment 1, 100 participants received either a suppression instruction or no instruction for an intrusive thought prior to sleep, and subsequently completed a dream diary. Participants instructed to suppress reported dreaming about the target thought more than controls; dream rebound was predicted by poorer performance on a working memory task. (...) In Experiment 2, 126 participants received either a suppression instruction or no instruction for an intrusive thought prior to sleep, and half of participants also had cognitive load of learning a 9-digit number. Participants receiving the suppression instruction under cognitive load reported greater dream rebound than other participants. These findings indicate that thought suppression prior to sleep leads to dream rebound, and this effect is enhanced by cognitive load. (shrink)

The brain adapts to changes that take place in the body. Deprivation of input results in size reduction of cortical representations, whereas an increase in input results in an increase of representational space. Amputation forms one of the most dramatic disturbances of the integrity of the body. The brain adapts in many ways to this breakdown of the afferent–efferent equilibrium. However, almost all studies focus on the sensorimotor consequences. It is not known whether adaptation takes place also at other “levels” (...) in the system. The present study addresses the question whether amputees dream about their intact body, as before the amputation, or about the body after the amputation and whether the dream content was a function of time since the amputation and type of amputation. The results show that the majority of the dreamers reported dreams about their intact body although the mean time that elapsed since the amputation was twelve years. There is no clear relation with the type of amputation. The results give modest evidence for the existence of a basic neural representation of the body that is, at least, partly genetically determined and by this relatively insensitive for changes in the sensory input. (shrink)

Unpleasant dreams occur much more frequently than many people realise. If one is a hedonistic utilitarian – or, at least, one thinks that dreams have positive or negative moral value in virtue of their experiential quality – then one has considerable reason to try to make such dreams more positive. Given it is possible to improve the quality of our dreams, we ought to be promoting and implementing currently available interventions that improve our dream experiences, and conducting research to find (...) new, more effective interventions. (shrink)

Hallucinatory states are experienced not only in connection with drugs and psychopathologies but occur naturally and spontaneously across the human circadian cycle: Our nightly dreams bring multimodal experiences in the absence of adequate external stimuli. The current study proposes a new, tighter measure of these hallucinatory states: Sleep onset, REM sleep, and non-REM sleep are shown to differ with regard to motor imagery indicating interactions with a rich imaginative world, and cognitive agency that could enable sleepers to recognize their hallucinatory (...) state. Mentation reports from the different states were analysed quantitatively with regard to two grammatical–semantic constructs, motor agency and cognitive agency. The present results support earlier physiological and psychological evidence in revealing a decline in cognitive functions and an increase in simulated interactions with a hallucinatory world, en route to normal REM sleep. This leads us to introduce the hypothesis that REM sleep, which exhibits remarkably high levels of sensorimotor processes, may have evolved to serve as a virtual laboratory for the development and rehearsal of embodied cognition. The new measure of hallucinatory states presented here may also hold implications for the study of executive functions and cognitions, which might be interesting, for example, for the investigation of lucid dreaming. (shrink)

Examines the lived experience of social encounters drawing on phenomenological insights.

There is wide agreement among dream researchers that emotional memories are activated during dreaming and that emotions play an important role in the thematic development of the dream. In accordanc...

Dream reports from 21 dreamers in which a metamorphosis of a person-like entity or animal occurred were coded for characters and animals and for inner states attributed to them (Theory of Mind). In myths and fairy tales, Kelly and Keil (1985) found that conscious beings (people, gods) tend to be transformed into entities nearby in the conceptual structure of Keil (1979). This also occurred in dream reports, but perceptual nearness seemed more important than conceptual nearness. In dream reports, most inanimate (...) objects involved in metamorphoses with person-like entities were objects such as statues that ordinarily resemble people physically, and moreover represent people. A metamorphosis of a person-like entity or animal did not lead to an increase in the amount of Theory of Mind attribution. We propose that a character-line starts when a character enters a dream; properties and Theory of Mind attributions tend to be preserved along the line, regardless of whether, metamorphoses occur on it. (shrink)

The content of dreams and changes to the self were investigated in students moving to University. In study 1, 20 participants completed dream diaries and memory tasks before and after they had left home and moved to university, and generated self images, “I am…” statements , reflective of their current self. Changes in “I ams” were observed, indicating a newly-formed ‘university’ self. These self, images and related autobiographical knowledge were found to be incorporated into recent dreams but not into dreams (...) from other periods. Study 2 replicated these findings in a different sample . We suggest that these data reflect a period of self-consolidation in which new experiences and self images are incorporated into autobiographical memory knowledge structures representing personal goals during sleep. (shrink)

Nielsen [Nielsen, T. . Felt presence: Paranoid delusion or hallucinatory social imagery? Consciousness and Cognition, 16, 975–983.] raises a number of issues and presents several provocative arguments worthy of discussion regarding the experience of the felt presence during sleep paralysis . We consider these issues beginning with the nature of FP and its relation to affective-motivational systems and provide an alternative to Nielsen’s reduction of FP to a purely spatial hallucination. We then consider implications of the “normal social imagery” model. (...) We can find only one specific empirical hypothesis articulated within this framework and it turns out to be one that we explicitly addressed in our original paper. We also review our position regarding the possible relation of FP during SP to a number of related anomalous experiences and contrast FP to anomalous vestibular-motor phenomena. We review our position that the neuromatrix concept, in the light of available evidence, is more appropriately applied to V-M experiences than FP. Finally, we pursue speculations, raised in Nielsen’s commentary, on the wider implications of FP. (shrink)

Artykuł zawiera prezentację i dyskusję wybranych zagadnień świadomości śniącej. Pierwsze z nich dotyczy znaczenia adaptacyjnego świadomości podczas snu. Drugie zagadnienie obejmuje charakterystykę kognitywnej świadomości śniącej. Efektem krytycznego przeglądu badań i koncepcji jest teza, że: (1) świadomość śniąca nie ma charakteru adaptacji biologicznej, (2) świadomość śniąca jest formą zdegradowanej reprezentacji kognitywnej w porównaniudo świadomości w stanie czuwania. W szczególności świadomość śniąca zawiera deficyty intencjonalności (uwagi) oraz wyższych form kognitywnych, w tym dysfunkcji wykonawczych.

Cognitive Science, Volume 46, Issue 1, January 2022.

In general, dreams are a novel but realistic simulation of waking social life, with a mixture of characters, motivations, scenarios, and positive and negative emotions. We propose that the sharing of dreams has an empathic effect on the dreamer and on significant others who hear and engage with the telling of the dream. Study 1 tests three correlations that are predicted by the theory of dream sharing and empathy: that trait empathy will be correlated with frequency of telling dreams to (...) others, with frequency of listening to others’ dreams, and with trait attitude towards dreams (for which higher scores indicate positive attitude). 160 participants completed online the Toronto Empathy Questionnaire and the Mannheim Dream Questionnaire. Pearson partial correlations were conducted, with age and sex partialled out. Trait empathy was found to be significantly associated with the frequency of listening to the dreams of others, frequency of telling one’s own dreams to others, and attitude towards dreams. Study 2 tests the effects of discussing dreams on state empathy, using an adapted version of the Shen (2010) state empathy scale, for 27 pairs of dream sharers and discussers. Dream discussion followed the stages of the Ullman (1996) dream appreciation technique. State empathy of the dream discusser towards the dream sharer was found to increase significantly as a result of the dream discussion, with a medium effect size, whereas the dream sharer had a small decrease in empathy towards the discusser. A proposed mechanism for these associations and effects is taken from the robust findings in the literature that engagement with literary fiction can induce empathy towards others. We suggest that the dream acts as a piece of fiction that can be explored by the dreamer together with other people, and can thus induce empathy about the life circumstances of the dreamer. We discuss the speculation that the story-like characteristics of adult human dreams may have been selected for in human evolution, including in sexual selection, as part of the selection for emotional intelligence, empathy, and social bonding. (shrink)

We investigated whether inconsistencies in previous studies regarding emotional experiences in dreams derive from whether dream emotions are self-rated or externally evaluated. Seventeen subjects were monitored with polysomnography in the sleep laboratory and awakened from every rapid eye movement sleep stage 5 min after the onset of the stage. Upon awakening, participants gave an oral dream report and rated their dream emotions using the modified Differential Emotions Scale, whereas external judges rated the participants’ emotions expressed in the dream reports, using (...) the same scale. The two approaches produced diverging results. Self-ratings, as compared to external ratings, resulted in greater estimates of emotional dreams; positively valenced dreams; positive and negative emotions per dream; and various discrete emotions represented in dreams. The results suggest that this is mostly due to the underrepresentation of positive emotions in dream reports. Possible reasons for this discrepancy are discussed. (shrink)

Models of dream analysis either assume a continuum of waking and dreaming or the existence of two dissociated realities. Both approaches rely on different methodology. Whereas continuity models are based on content analysis, discontinuity models use a structural approach. In our study, we applied both methods to test specific hypotheses about continuity or discontinuity. We contrasted dream reports of congenitally deaf-mute and congenitally paraplegic individuals with those of non-handicapped controls. Continuity theory would predict that either the deficit itself or compensatory (...) experiences would surface in the dream narrative. We found that dream form and content of sensorially limited persons was indifferent from those of non-handicapped controls. Surprisingly, perceptual representations, even of modalities not experienced during waking, were quite common in the dream reports of our handicapped subjects. Results are discussed with respect to feedforward mechanisms and protoconsciousness theory of dreaming. (shrink)

This study focuses on a set of dreams related to the September 11, 2001 terrorist attacks and their aftermath, using content analysis and cognitive psychology to explore the interweaving of external public catastrophe and internal psychological processes. The study tests several recent claims in contemporary dream research, including the central image theory of Hartmann [Hartmann, E., & Basile, R. . Dream imagery becomes more intense after 9/11/01. Dreaming, 13, 61–66; Hartmann, E., & Brezler, T. . A systematic change in dreams (...) after 9/11/01. Sleep, 31, 213–218], the media exposure factor postulated by Propper [Propper, R. E., Stickgold, R., Keeley, R., & Christman, S. D. . Is television traumatic? Dreams, stress, and media exposure in the aftermath of September 11, 2001. Psychological Science, 18, 334–340], the continuity hypothesis of Domhoff [Domhoff, W. G. . Finding meaning in dreams: A quantitative approach. New York: Plenum], the cognitive and metacognitive approach of Kahan [Kahan, T. L. . Consciousness in dreaming: A metacognitive approach. In K. Bulkeley , Dreams: A reader on the religious, cultural, and psychological dimensions of dreaming . New York: Palgrave], and the threat simulation theory of Revonsuo [Revonsuo, A. . The reinterpretation of dreams: An evolutionary hypothesis of the function of dreaming. Behavioral and Brain Sciences, 23, 877–901]. Our findings suggest the terrorist attacks had a tangible impact on the content of many people’s dreams, but did not fundamentally alter the cognitive processing features of their dreaming. The 9/11 attacks affected what they dreamed about, but not the way they dreamed. (shrink)

Self-produced tactile stimulation usually feels less tickly—is perceptually attenuated—relative to the same stimulation produced externally. This is not true, however, for individuals with schizophrenia. Here, we investigate whether the lack of attenuation to self-produced stimuli seen in schizophrenia also occurs for normal participants following REM dreams. Fourteen participants were stimulated on their left palm with a tactile stimulation device which allowed the same stimulus to be generated by the participant or by the experimenter. The level of self-tickling attenuation did not (...) differ between REM and non-REM sleep awakening conditions, where presence or absence of an accompanying dream was not controlled for. However, for the female participants, when awakening occurred from an REM sleep dream, self-stimulation ratings were higher than for external stimulation, whereas ratings after NREM sleep unaccompanied by a dream were lower for self-stimulation than for external stimulation. These results indicate deficits in self-monitoring and a confusion between self- and externally generated stimulation accompany REM dream formation. (shrink)

The question of why music evolved has been contemplated and debated for centuries across multiple disciplines. While many theories have been posited, they still do not fully answer the question of why humans began making music. Adding to the effort to solve this mystery, we propose the socio-affective fiction (SAF) hypothesis. Humans have a unique biological need for emotion regulation strengthening. Simulated emotional situations, like dreams, can help address that need. Immersion is key for such simulations to successfully exercise people's (...) emotions. Therefore, we propose that music evolved as a signal for SAF to increase the immersive potential of storytelling and thereby better exercise people's emotions. In this review, we outline the SAF hypothesis and present cross-disciplinary evidence. (shrink)