I propose a narrative fabrication thesis of dream reports, according to which dream reports are often not accurate representations of experiences that occur during sleep. I begin with an overview of anti-experience theses of Norman Malcolm and Daniel Dennett who reject the received view of dreams, that dreams are experiences we have during sleep which are reported upon waking. Although rejection of the first claim of the received view, that dreams are experiences that occur during sleep, is implausible, I evaluate (...) in more detail the second assumption of the received view, that dream reports are generally accurate. I then propose a “narrative fabrication” view of dreams as an alternative to the received view. Dream reports are often confabulated or fabricated because of poor memory, bizarre dream content, and cognitive deficits. It is well documented that narratives can be altered between initial rapid eye movement sleep awakenings and subsequent reports. I argue that we have reason to suspect that initial reports are prone to inaccuracy. Experiments demonstrate that subjects rationalize strange elements in narratives, leaving out supernatural or bizarre components when reporting waking memories of stories. Inaccuracies in dream reports are exacerbated by rapid memory loss and bizarre dream content. Waking memory is a process of reconstruction and blending of elements, but unlike waking memory, we cannot reality-test for dream memories. Dream experiences involve imaginative elements, and dream content cannot be verified with external evidence. Some dreams may involve wake-like higher cognitive functions, such as lucid dreams. Such dreams are more likely to elicit accurate reports than cognitively deficient dreams. However, dream reports are generally less accurate than waking reports. I then propose methods which could verify the narrative fabrication view, and argue that although the theory cannot be tested with current methods, new techniques and technologies may be able to do so in the future. -/- . (shrink)

Cognitive theories claim, whereas non-cognitive theories deny, that cognitive access is constitutive of phenomenology. Evidence in favor of non-cognitive theories has recently been collected by Block and is based on the high capacity of participants in partial-report experiments compared to the capacity of the working memory. In reply, defenders of cognitive theories have searched for alternative interpretations of such results that make visual awareness compatible with the capacity of the working memory; and so the conclusions of such experiments remain controversial. (...) Instead of entering the debate between alternative interpretations of partial-report experiments, this paper offers an alternative line of research that could settle the discussion between cognitive and non-cognitive theories of consciousness. Here I relate the neural correlates of cognitive access to empirical research into the neurophysiology of dreams; cognitive access seems to depend on the activity of the dorsolateral prefrontal cortex. However, that area is strongly deactivated during sleep; a period when we entertain conscious experiences: dreams. This approach also avoids the classic objection that consciousness should be inextricably tied to reportability or it would fall outside the realm of science. (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)

Mulder and colleagues [Mulder, T., Hochstenbach, J., Dijkstra, P. U., Geertzen, J. H. B. . Born to adapt, but not in your dreams. Consciousness and Cognition, 17, 1266–1271.] report that a majority of amputees continue to experience a normally-limbed body during their night dreams. They interprete this observation as a failure of the body schema to adapt to the new body shape. The present note does not question this interpretation, but points to the already existing literature on the phenomenology of (...) the phantom limb in dreams. A summary of published investigations is complemented by a note on phantom phenomena in the dreams of paraplegic patients and persons born without a limb. Integration of the available data allows the recommendation for prospective studies to consider dream content in more detail. For instance, “adaptation” to the loss of a limb can also manifest itself by seeing oneself surrounded by amputees. Such projective types of anosognosia in nocturnal dreams should also be experimentally induced in normally-limbed individuals, and some relevant techniques are mentioned. (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.

The well-known distinction between access consciousness and phenomenal consciousness has moved away from the conceptual domain into the empirical one, and the debate now is focused on whether the neural mechanisms of cognitive access are constitutive of the neural correlate of phenomenal consciousness. In this paper, I want to analyze the consequences that a negative reply to this question has for the cognitive phenomenology thesis – roughly the claim that there is a “proprietary” phenomenology of thoughts. If the mechanisms responsible (...) for cognitive access can be disentangled from the mechanisms that give rise to phenomenology in the case of perception and emotion, then the same disentanglement is to be expected in the case of thoughts. This, in turn, presents, as I argue, a challenge to the cognitive phenomenology thesis: either there are thoughts with cognitive phenomenology we lack cognitive access to or there are good reasons to doubt that there is such a thing as cognitive phenomenology. I discuss a... (shrink)

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. (shrink)

Standard accounts of delusion explain them as responses to experience. Cognitive models of feature binding in the face recognition systems explain how experiences of mismatch between feelings of "familiarity" and faces can arise. Similar mismatches arise in phenomena such as déjà and jamais vu in which places and scenes are mismatched to feelings of familiarity. These cognitive models also explain similarities between the phenomenology of these delusions and some dream states which involve mismatch between faces, feelings of familiarity and identities. (...) Given these similarities it makes sense to retain that aspect of the standard account in the face of revisionist arguments that feature binding anomalies which lead to delusions of misidentification are not consciously experienced. (shrink)

Delusional misidentification is commonly understood as the product of an inference on the basis of evidence present in the subject's experience. For example, in the Capgras delusion, the patient sees someone who looks like a loved one, but who feels unfamiliar, so they infer that they must not be the loved one. I question this by presenting a distinction between “recognition” and “identification.” Identification does not always require recognition for its epistemic justification, nor does it need recognition for its psychological (...) functioning. Judgments of identification are often the product of a non-inferential mechanism. Delusional misidentification arises as the product of this mechanism malfunctioning. (shrink)

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. (shrink)

Our eyes, bodies, and perspectives are constantly shifting as we observe the world. Despite this, we are very good at distinguishing between self-caused visual changes and changes in the environment: the world appears mostly stable despite our visual field moving around. This, it seems, also occurs when we are dreaming. As we visually investigate the dream environment, we track moving objects with our dream eyes, examine objects, and shift focus. These movements, research suggests, are reflected in the rapid movements or (...) saccades of our sleeping eyes. Do we really see the dream world in the same way that we see the real world? If we do, how could dreaming, usually assumed to be mind-generated hallucinations, replicate such an experience? This problem would be deflated if dreams are not hallucinations at all, but rather imagination, illusion or simply unrealistic. I argue that imagination and illusion views do not satisfactorily explain away the problem of vision and action in sleep. The imagination model is not a complete description of dreaming that is consistent with empirical research, and it is unlikely that the visual dream world is an illusion. Given that the dreaming visual experience is most likely active, hallucinatory, and at times a realistic world simulation, there are important implications for our understanding of visual perception and its relationship to movement. Evidence suggests that our dream eyes investigate the dream world as our waking eyes investigate the waking world. If changes to the unconsciously generated dream environment are perceived as external and unintentional while dream body movements are perceived as self-generated and intentional, current theory of visual perception may have to be expanded to account for how the dreaming mind generates a stable world in which we track and visually explore mind-generated objects. (shrink)

Dream is a state of consciousness characterized by internally-generated sensory, cognitive and emotional experiences occurring during sleep. Dream reports tend to be particularly abundant, with complex, emotional, and perceptually vivid experiences after awakenings from rapid eye movement sleep. This is why our current knowledge of the cerebral correlates of dreaming, mainly derives from studies of REM sleep. Neuroimaging results show that REM sleep is characterized by a specific pattern of regional brain activity. We demonstrate that this heterogeneous distribution of brain (...) activity during sleep explains many typical features in dreams. Reciprocally, specific dream characteristics suggest the activation of selective brain regions during sleep. Such an integration of neuroimaging data of human sleep, mental imagery, and the content of dreams is critical for current models of dreaming; it also provides neurobiological support for an implication of sleep and dreaming in some important functions such as emotional regulation. (shrink)

In this paper, we address the different ways in which dream research can contribute to interdisciplinary consciousness research. As a second global state of consciousness aside from wakefulness, dreaming is an important contrast condition for theories of waking consciousness. However, programmatic suggestions for integrating dreaming into broader theories of consciousness, for instance by regarding dreams as a model system of standard or pathological wake states, have not yielded straightforward results. We review existing proposals for using dreaming as a model system, (...) taking into account concerns about the concept of modeling and the adequacy and practical feasibility of dreaming as a model system. We conclude that existing modeling approaches are premature and rely on controversial background assumptions. Instead, we suggest that contrastive analysis of dreaming and wakefulness presents a more promising strategy for integrating dreaming into a broader research context and solving many of the problems involved in the modeling approach. (shrink)

To test whether mental activities collected from non-REM sleep are influenced by REM sleep, we suppressed REM sleep using clomipramine 50 mg or placebo in the evening, in a double blind cross-over design, in 11 healthy young men. Subjects were awakened every hour and asked about their mental activity. The marked REM-sleep suppression induced by clomipramine did not substantially affect any aspects of dream recall . Since long, complex and bizarre dreams persist even after suppressing REM sleep either partially or (...) totally, it suggests that the generation of mental activity during sleep is independent of sleep stage. (shrink)

This study investigated the relationship between dream emotion and dream character identification. Thirty-five subjects provided 320 dream reports and answers to questions on characters that appeared in their dreams. We found that emotions are almost always evoked by our dream characters and that they are often used as a basis for identifying them. We found that affection and joy were commonly associated with known characters and were used to identify them even when these emotional attributes were inconsistent with those of (...) the waking state. These findings are consistent with the finding that the dorsolateral prefrontal cortex, associated with short-term memory, is less active in the dreaming compared to the wake brain, while the paleocortical and subcortical limbic areas are more active. The findings are also consistent with the suggestion that these limbic areas have minimal input from the dorsolateral prefrontal cortex in the dreaming brain. (shrink)

Over the last decade or so, several researchers have considered the predictive processing framework (PPF) to be a useful perspective from which to shed some much-needed light on the mechanisms behind psychosis. Most approaches to psychosis within PPF come down to the idea of the “atypical” brain generating inaccurate hypotheses that the “typical” brain does not generate, either due to a systematic top-down processing bias or more general precision weighting breakdown. Strong at explaining common individual symptoms of psychosis, such approaches (...) face some issues when we look at a more general clinical picture. In this paper, we propose an update on the current accounts of psychosis based on the realization that a neurotypical brain constantly generates non-actual, de-coupled, counterfactual hypotheses as part of healthy cognition. We suggest that what is going on in psychosis, at least in some cases, is not so much a generation of erroneous hypotheses, but rather an inability to correctly use the counterfactual ones. This updated view casts “accurate” cognition as more fragile and delicate, but also closes the gap between psychosis and typical cognition. (shrink)

Jennifer Radden has drawn attention to two features of delusion, ambivalence and subjectivity, which are problematic for theories of delusion that treat delusions as empirical beliefs. She argues for an ‘attitude’ theory of delusion. I argue that once the cognitive architecture of delusion formation is properly described the debate between doxastic and attitude theorists loses its edge. That architecture suggests that delusions are produced by activity in the ‘default mode network’ unsupervised by networks required for decontextualized processing. The cognitive properties (...) of these networks explain the features of delusion which generate the debate between doxastic and attitude theorists. (shrink)

Dreams provide a compelling problem for sensorimotor enactivists like Alva Noë: they seem to replicate our perceptual experiences without sensorimotor interaction with distal sensory stimuli. Noë has responded by saying that dreams actually fail to replicate perceptual experiences in virtue of their lack of detail and stability. Noë's opponents have replied by pointing out that some dreams are richly detailed and stable, and that instability and a lack of detail in dreams can anyway be explained in terms of the underlying (...) neural activity. In this paper, I develop how the sensorimotor enactivist should respond: dreams fail to replicate perceptual experiences because they are exhausted by what shows up at a given moment in phenomenal consciousness, while perceptual experiences go beyond this to include everything accessible via sensorimotor exploration. This difference permeates all levels of experience, so that dreams can't even replicate perceptual experiences of simple shapes and colors. Further, unlike detail and stability, there are not obvious neural explanations of this phenomenal difference. (shrink)

Current models of auditory verbal hallucinations tend to focus on the mechanisms underlying their occurrence, but often fail to address the content of the auditory experience. In other words, they tend to ask why there are AVHs at all, instead of asking why, given that there are AVHs, they have the properties that they have. One such property, which has been largely overlooked and which we will focus on here, is why the voices are often experienced as coming from agents, (...) and often specific, individualised agents. In this article, we argue not only that the representation of agents is important in accurately describing many cases of AVH, but also that deeper reflection on what is involved in the representation of agents has potentially vital consequences for our aetiological understanding of AVH, namely, for understanding how and why AVHs come about. (shrink)

Recent studies suggest that lucid dreaming might be associated with increased brain activity over frontal regions during rapid eye movement sleep. By applying transcranial direct current stimulation , we aimed to manipulate the activation of the dorsolateral prefrontal cortex during REM sleep to increase dream lucidity. Nineteen participants spent three consecutive nights in a sleep laboratory. On the second and third nights they randomly received either 1 mA tDCS for 10 min or sham stimulation during each REM period starting with (...) the second one. According to the participants’ self-ratings, tDCS over the DLPFC during REM sleep increased lucidity in dreams. The effects, however, were not strong and found only in frequent lucid dreamers. While this indicates some preliminary support for the involvement of the DLPFC in lucid dreaming, further research, controlling for indirect effects of stimulation and including other brain regions, is needed. (shrink)

The distinction between phenomenal and access consciousness is central to debates about consciousness and its neural correlates. However, this distinction has often been limited to the domain of perceptual experiences. On the basis of dream phenomenology and neuroscientific findings this paper suggests a theoretical framework which extends this distinction to dreaming, also in terms of plausible neural correlates. In this framework, phenomenal consciousness is involved in both waking perception and dreaming, whereas access consciousness is weakened, but not fully eliminated, during (...) dreaming. However, access consciousness is more active during lucid dreaming. The proposed framework accounts for different aspects of dream phenomenology, including levels of integration of perceptual, cognitive and affective features in dreams, bizarreness, dream amnesia and the occurrence of meta-awareness and accessibility in lucid dreaming. Self-related experiences and their neural substrates are suggested to be differently involved in waking cognition and dreaming. Further, phenomenal consciousness during both waking and dream experiences involve widespread recurrent interactions and convergence-divergence zones in the thalamo-cortico-limbic system, activated before conscious access in global workspace areas. Finally, we discuss the relationships of the proposed framework with other neurocognitive theories and models of consciousness and major theories of dreaming, and propose novel experimental predictions. (shrink)

The relationship between dream content and waking life experiences remains difficult to decipher. However, some neurobiological findings suggest that dreaming can, at least in part, be considered epiphenomenal to ongoing memory consolidation processes in sleep. Both abnormalities in sleep architecture and impairment in memory consolidation mechanisms are thought to be involved in the development of psychosis. The objective of this study was to assess the continuity between delusional contents and dreams in acutely psychotic patients. Ten patients with a single fixed (...) and recurring delusional content were asked to report their dreams during an acute psychotic break. Sixteen judges with four different levels of acquaintance to the specific content of the patients’ delusions were asked to group the dreams, expecting that fragments of the delusional thought would guide the task. A mathematical index was developed in order to compare correct groupings between the four groups of judges. Most judges grouped the dreams slightly above chance level and no relevant differences could be found between the four groups [F = 1.297; p = n.s.]. Scoring of dreams for specific delusional themes suggested a continuity in terms of dream and waking mentation for two contents . These findings seem to suggest that at least some delusional contents recur within patients’ dreams. Future studies will need to determine whether such continuity reflects ongoing consolidation processes that are relevant to current theories of delusion formation and stabilization. (shrink)

Comparing the phenomenology, neurochemical pathology, and psychopharmacology of hallucinations and dreaming is limited by the available data. Evidence to date reveals no simple correspondence between the two states. Differences in the phenomenology of visual hallucinations and the visual component of dreams may reflect variations in visual context acting on the same underlying mechanism – the minimal visual input during dreaming contrasts with the more substantial perceived context in hallucinations. Variations in cholinergic, dopaminergic and serotonergic neurotransmitter function during sleep and during (...) hallucinations in Lewy body dementias, together with relevant drug effects suggest that, on the whole, different, potentially opposite, changes characterise the two states. A similar analysis of other psychotic features in Lewy body dementia and other disorders suggests that, in contrast to hallucinations, there may be more convincing parallels between dreaming and delusional states. (shrink)