63. This is an additional fact to point to the activation of other mechanisms capable of producing wakefulness and desynchronized sleep, including dreaming. Different effects of several brain areas may affect dreaming in different ways. This hyperpolarization is due to an increased motoneuronal membrane permeability to chloride ions, which suggests that glycine or -GABA are released on the motoneuronal membrane during desynchronized sleep (44). Sigmund Freuds theory of dreams suggests that dreams represent unconscious desires, thoughts, wish fulfillment, and motivations. Behav Brain Sci 2000;23:793-842. Unable to load your collection due to an error, Unable to load your delegates due to an error. Nature 1989;340:474-6. Nature 1996;383:163-6. De Sanctis, in 1899, in his book I Sogni, Studi Clinici ed Psicologici di un Alienista (Dreams, Clinical and Psychological Studies of a Psychiatrist), cites no less than 323 articles and books dealing with dreams, which proves that the objective study of dreams did not start during the middle of the 20th century, as is usually taken for granted (4). Hernndez-Pen R. A neurophysiologic model of dreams and hallucinations. When they sleep, fishes keep quiet, with no apparent movements, and then they can be easily fished with a hand.". Visual dreams provoke eye movements. Christy B, Nathans D. DNA binding site of the growth factor-inducible protein Zif268. A regular oscillation modulates the amplitude of the potentials. There is experimental evidence that eye movements are generated near the nucleus of the abducent nerve but Pompeiano (1967) does not agree with this view (10,41). A theory that has many In blind people, whose auditory and somesthetic sensitivity is enhanced, auditory dreams predominate, as expected from their high auditory sensibility. eCollection 2017. In 1944 Obhlmeyer, Brilmayer & Uhlstrung (10) observed that in humans penile erection occurs during sleep at intervals of 85 minutes, which is the average duration of a sleep cycle. and transmitted securely. Dement WC. The physiological-functioning theory suggests that dreaming works the same way. FOIA Analysis of psychological theories concerning functions of dreams. The earliest theory to emerge, Freuds psychoanalytic theory, takes an observational approach to identifying the function that dreams serve. Freud theorized that dreams are the result of unfulfilled wishes or desires in the subjects life. Spreng LF, Johnson LC, Lubin A. Autonomic correlates of eye movement bursts during state REM sleep. If the animal is trying to identify the source of an odor that is located at a large distance, snout movements are expected to span wide angles at low frequencies, whereas when the source is near such movements are expected to span narrow angles, at high frequencies, just as during wakefulness. Such a configuration is subsequently compared to memorized patterns and then, and only then, it can be identified by means of the conscious process. Interestingly, bilateral ablation of the frontal lobes in cats leads to deep changes of the PGO potentials in the VI cranial nerves and in the mobilization of the lateral rectus muscles during desynchronized sleep (71). Chaudhuri A. Neural activity mapping with inducible transcription factors. In rats we found similar potentials in the amygdala as related to olfactory dreams, expressed as rostrum movements (32). Unfortunately, despite the opinion of great scientists of the past, most researchers that deal with sleep and dreaming, probably moved by philosophical, religious prejudice and a faulty reasoning, do not accept the idea that non-human animals do dream. Arch Gen Psychiat 1966;14:238-48. Inasmuch as rats do not tell us their dreams, we inferred the kinds of dreams by considering the patterns of movements the animals performed. Two major theories have been proposed regarding the neural circuits involved in dreaming. Vertes RP, Kocsis B. Brainstem-diencephalo-septohippocampal systems controlling the theta rhythm of the hippocampus. Such electrophysiological studies demonstrate that the abovementioned sites in the central nervous system are involved in the oniric movements but they do not prove that such structures generate them. Inasmuch as dreaming seems to occur in most birds and mammals, it is unlikely that it has no function in the animal organism. Stimulus response theory of dream: The stimulus response theory which existed prior to Freud is based upon the associationistic stimulus response view. This theory stresses the relationship between brain changes during sleep and changes in perceptual efficiency. Some disturbing stimuli force activity into one portion of the cerebral cortex. One is that dreams are generated by the activation of neural activity in the brainstem and its signal transmission to the cortex. Erlbaum 1992. There are many hypotheses to account for the existence of dreams but it is still a matter of debate why and what for we dream. Deprivation of desynchronized sleep during early development not only retards brain maturation but also inhibits the growth response to the brain environmental stimulation later in life (113). In this review, the neural circuits underlying dreaming and the physiological functions associated with it are summarized. The PGO potentials are correlates of dreams. Foulkes D. A cognitive-psychological model of REM dream production. Neurosc Res 1993;17:181-202. 59. The discovery of REM sleep kickstarted a flurry of scientific research into the mechanisms of the sleeping brain. Those that are specific to certain behaviors. Brainstem control of the events of REM sleep. Arch Ital Biol 1963;101:648-68. 18. Also, correlation is high when theta waves in the thalamic reticular nucleus are matched to those occurring in the nucleus reticularis pontis oralis. Hodes R, Dement WC. In nocturnal macrosmatic animals, olfaction is the predominant sensory channel and their vibrissae are usually very long, to detect the presence of objects at relatively large distances. 102. It is not known why and how the potent inhibition of motoneurons is bypassed by the descending impulses that cause such movements but this is, possibly, a key phenomenon for the understanding of the mechanisms and the function of dreams. Changes in hippocampal gene expression associated with the induction of long-term potentiation. Selective deactivation of the dorsolateral prefrontal cortex has been found in desynchronized sleep. Hansotia P, Broste S, Ruggles K, Wall R, Friske M. Eye movement patterns in REM sleep. 73. & Bertini, M. Bethesda, MD 20894, Web Policies 84. In humans the electro-oscillograms during desynchronized sleep are expressed as overall cortical desynchronization, whence the adequacy of the name created by Moruzzi, desynchronized sleep. 112. Decety J, Jeannerod M, Durozard DR, Baveal J. 109. In 1999, Ribeiro et al., assaying zif-268 expression in control rats and in rats subjected to a rich environment training, found that in control animals this gene protein generally decreased, mainly in the cerebral cortex, from wakefulness to synchronized sleep and from synchronized to desynchronized sleep (109). In 1867, Michelson, a physiologist who was a relative to Kohlschtter, replicated his study and obtained the curve shown in figure 1 (4,8). As pointed Confrontations Psychiatriques 1986;27:153-81. Hence, experiments with such animals are extremely valuable and thus will be emphasized in the present review. The narrower is the angle of rotation, the lower is the recorded potential, which happens when attention is being directed to a very small part of the object or when the object is very near. Web5 Theories on dreaming . This site needs JavaScript to work properly. The https:// ensures that you are connecting to the The number of PGO potentials undergoes a high increase after the frontal ablation, which is suggestive of a tonic inhibition of these potentials by the frontal cortex. Magoun HW, Rhines R. An inhibitory mechanism in the bulbar reticular formation. 11. Freuds wish-fulfillment. A nerve growth factor-induced gene encodes a possible trancriptional regulatory factor. Guazzi M, Baccelli G, Zanchetti A. Carotid body chemoreceptors: physiological role in buffering fall in blood pressure during sleep. University of Chicago Press, Chicago & London edition 1985. Bol Inst Est Md Biol Mxico 1962;20:155-64. Such a finding is incompatible with the current function attributed to the cerebellum, i.e., only correction of movements. doi: 10.1093/nc/nix009. Dreams are still taken by a majority of the human kind as premonitory, ascribing them the function of telling us that something important will happen. Arch Psychiat Nervenkrankh 1938;109:1-17. Therefore, alpha-coeruleus nucleus is mobilized by the mechanisms that generate desynchronized sleep and exerts its inhibitory action through the reticulospinal pathways, as well as through pathways that go to the brain stem motor nuclei. Such activation of zif-268, which is likely to be correlated with the effect of learning on desynchronized sleep, was larger in the frontal and hippocampal cortices, where memorization is well known to occur. Accordingly, they are known as PGO (pontine, occipital cortex and lateral geniculate nucleus) potentials. Vanni-Mercier G, Pelisson D, Goffart L, Sakai K, Jouvet M. Eye saccade dynamics during paradoxical sleep in the cat. Another fancy hypothesis is the one that proposes that we dream to forget, in order to delete "unwanted" information by reverse learning or unlearning (118). 58. J Biol Chem 1995;270:24361-9. Muscle atonia during desynchronized sleep is, as stated above, generated in the alpha-coeruleus nucleus and involves both direct and indirect pathways that inhibit the motoneurons. Such movements may take the sleeper to fall off the bed. The subjects of dreams are broad-ranging and complex, incorporating self-image, fears, insecurities, strengths, grandiose ideas, sexual orientation, desire, jealousy and love". Harvey Lect 1963;58:233-97. Therefore, any neural event, be it running or just thinking, or dreaming, requires a large amount of oxygen, which is carried to the nervous system by the blood through powerful hemodynamic adjustments, such as increase in blood pressure, heart rate and central blood flow (21,25,26). In 1896 Weed & Halam (4) published the first quantification of dreams content. In: M. C. Hepp-Reymond & G. Marini (eds.) Candia O, Favale E, Guissani A, Rossi G. Blood pressure during natural sleep and during sleep induced by electrical stimulation of the brain stem reticular formation. 127. 76. Roberts LA, Higgins MJ, O'Shaughnessy CT, Stone TW, Morris BJ. ", "As to the oviparous creatures, it is obvious that they sleep but it is impossible to state that they dream. General Learning Press, 1970. Erlbaum, 1992. During REM sleep, several physiological changes also take place. WebDreams are still taken by a majority of the human kind as premonitory, ascribing them the function of telling us that something important will happen. 39. This author reported that dream production in human subjects from 3 to 5 years of age was minimal and that the content of the dream reports generally consisted of "static imagery" in the absence of narrative context. Physiol., Springer-Verlag, Berlin 1972:166-307. According to Hobson, Pace-Schotter & Stickgold (2000), since image studies show activation of "limbic" and "paralimbic" structures of the forebrain during desynchronized sleep, as compared to wakefulness (120,126-128), emotion may be a primary shaper of dream plots, rather than playing a secondary role plot instigation. Grimm R, Tischmeyer W. Complex patterns of immediate gene induction in rat brain following brightness discrimination training and pseudotraining. Europ J Neurosci 1994;6:1298-1306. J Ment Nerv Dis 1966;141:623-50. Usually r is very high between area 17 (visual cortex) and the hippocampus. (eds.) 6. Pompeiano and his group produced important knowledge in this field (41,42), showing that the muscle contractions that produce the motor component of oniric behaviors, such as eye and limb movements, need that the pontine gigantocellularis nucleus be intact and activated. C R Soc Biol (Paris) 1969;163:181-6. 83. Not only theta waves do occur in the cerebellar cortex during desynchronized sleep but also spindles and delta waves are found in this organ in synchronized sleep, just as in neocortical areas. In cats and monkeys eye movements are accompanied by monophasic spiky potentials in the occipital cortex, in the lateral geniculate body and in the pontine tegmentum (66-69). Timo-Iaria C. Early research on dreaming. The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). Roffwarg HP, Herman J, Lamstein S. The middle ear muscles: predictability of their phasic action in REM sleep from dream recall. Brain activity during this time keeps us As any neural information, it has to be analyzed, so that the nervous impulses, which carry it be decoded and integrated as a specific neural configuration, that contains all the information released (or revoked) from the mnemonic archives. "Insects are also creatures that do sleep, so much so that they can be seen resting with no movements whatsoever. Its is noteworthy that Weed & Halam's data, published in 1896, are close to those reported by Rechtschaffen & Buchignani in 1992, which was calculated as the mean of the average of seven different studies published by other authors (40). Acta Med Iug 1978;32:45-50. Heiss W-D, Pawlik G, Herholz K, Wagner R, Weinhard K. Regional cerebral glucose metabolism in man during wakefulness, sleep, and dreaming. Considering dreams as hallucinations, Hernndez-Pen (1966) theorized that they are possible because the system responsible for wakefulness is inactivated during sleep, releasing memory tracings which are brought to consciousness. Springer Verlag, Frankfurt 1953. When only one side of the reticular formation is also destroyed, the same pattern of recovery does occur; if the other side of the reticular formation is also destroyed after two or three weeks, recovery of wakefulness and desynchronized sleep is even faster than when both sides are lesioned at the same time. Rapid increase of an immediate early gene messenger RNA in hippocampal neurons by synaptic NMDA receptor activation. 115. While the how and why of dreaming may be explored using physiological and biological methods, dreaming is also a subjective experience involving a form of mentation that can offer representations of an individual's internal world. Brain Res 1985;327:362-6. The reason why when we dream we are walking we do not get out of the bed and really walk, or when we dream we are talking to someone we do not really talk, is that neural circuits located in the neighborhood of locus coeruleus, in the pontine tegmentum, inhibit the motoneurons and do not allow the real movements to occur. It may be more appropriate to explain the latter authors' results by reasoning that dreams are originated in memorized information and are, accordingly, closely related to events occurring before sleep. This causes the amygdala and hippocampus to become active, which help to influence the brain systems that control sensations, memories, and emotions. Sakai K, Sastre JP, Kanamori N, Jouvet M. State-specific neurons in the ponto-medullary reticular formation with special reference to the postural atonia during paradoxical sleep in the cat. However, during desynchronized sleep it was drastically reduced, being entirely inhibited for most of the time. One is that dreams are generated by the activation of neural activity in the brainstem and its signal transmission to the cortex. Intermediate state of sleep in the cat. Physiol Behav 1974;12:293-5. Ergebn. Axons from neurons of the nucleus reticularis gigantocellularis descend along the ventral and ventrolateral funiculi and connect with inhibitory interneurons in the spinal cord (55,56). 133. Esoteric power, useless, useful: considerations about dreams in cognitive-behavioural therapy. 2022 Nov 3;12(11):1832. doi: 10.3390/jpm12111832. government site. 10. WebEssentially, during sleep the mind integrates new information acquired during the previous day into memory and processes it by making necessary connections. Such high values of r may mean that theta waves arrive in such areas almost synchronously, coming from some other sites in the central nervous system. 35. During the first half of the twentieth century, despite the heavy influence of psychoanalysis, dreaming was again but sporadically studied scientifically. Metabolism during desynchronized sleep tends, in fact, to be equal to or even larger than that of waking (131,132). 111. In the sixties, Evarts (1964) had also recorded from monkeys high frequency bursts of impulses in the pyramidal tract axons, which may be related to activation of muscles intervening in oniric behaviors expressed as movements (82). Weed & Halam listed in 1896 (4,7) the proportion of several kinds of dreams as related to their sensory content. Rechtschaffen A, Buchignani C. The visual appearance of dreams. Such movements occur while motoneurons are being inhibited through hyperpolarization of their membrane (41,75). Esquirol, one of the French psychiatrists who started the revolution that changed the ancient (an cruel) view of the mental diseases, spent several hours at night observing how his patients behaved during sleep and concluded that their movements while asleep were related to their dreams, just as Aristotle had found long ago. Roffwarg et al. A comparison of presleep and REM sleep thematic content. (1996) and Braun et al. ), Ermdung, Schlaf und Traum, Fischer Taschenbuch Verlag, Sttutgart 1971:173-242. This author "thus proposes a psychoanalytical model of dreaming, in which dreams constitute a way of representing the individual's inner world with internal objects related with one another and with the self" (135). In: Baust, W. Winson (1990) believes that dreams "reflect an individual strategy for survival. 107. Much experimental work is needed before a convincing function can be ascribed to the fascinating physiological phenomenon that is dreaming. 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