From the neurophysiological perspective, thinking in dreaming and the quality of dream thought have been considered hallucinatory, bizarre, illogical, improbable, or even impossible. This empirical phenomenological research concentrates on testing whether dream thought can be defined as rational in the sense of an intervening mental process between sensory perception and the creation of meaning, leading to a conclusion or to taking action. From 10 individual dream journals of male participants aged 22–59 years and female participants aged 25–49 years, we delimited (...) four dreams per journal and randomly selected five thought units from each dream for scoring. The units provided a base for testing a hypothesis that the thought processes of dream construction are rational. The results support the hypothesis and demonstrate that eight fundamental rational thought processes can be applied to the dreaming process. (shrink)

Several theories claim that dreaming is a random by-product of REM sleep physiology and that it does not serve any natural function. Phenomenal dream content, however, is not as disorganized as such views imply. The form and content of dreams is not random but organized and selective: during dreaming, the brain constructs a complex model of the world in which certain types of elements, when compared to waking life, are underrepresented whereas others are over represented. Furthermore, dream content is consistently (...) and powerfully modulated by certain types of waking experiences. On the basis of this evidence, I put forward the hypothesis that the biological function of dreaming is to simulate threatening events, and to rehearse threat perception and threat avoidance. To evaluate this hypothesis, we need to consider the original evolutionary context of dreaming and the possible traces it has left in the dream content of the present human population. In the ancestral environment human life was short and full of threats. Any behavioral advantage in dealing with highly dangerous events would have increased the probability of reproductive success. A dream-production mechanism that tends to select threatening waking events and simulate them over and over again in various combinations would have been valuable for the development and maintenance of threat-avoidance skills. Empirical evidence from normative dream content, children's dreams, recurrent dreams, nightmares, post traumatic dreams, and the dreams of hunter-gatherers indicates that our dream-production mechanisms are in fact specialized in the simulation of threatening events, and thus provides support to the threat simulation hypothesis of the function of dreaming. Key Words: dream content; dream function; evolution of consciousness; evolutionary psychology; fear; implicit learning; nightmares; rehearsal; REM; sleep; threat perception. (shrink)

Thirty-eight “practiced” dreamers and 50 “novice” dreamers completed questionnaires assessing the cognitive, metacognitive, and emotional qualities of recent waking and dreaming experiences. The present findings suggest that dreaming cognition is more similar to waking cognition than previously assumed and that the differences between dreaming and waking cognition are more quantitative than qualitative. Results from the two studies were generally consistent, indicating that high-order cognition during dreaming is not restricted to individuals practiced in dream recall or self-observation. None of the measured (...) features was absent or infrequent in reports of either dreaming or waking experiences. Recollections of dreaming and waking experiences were similar for some cognitive features and different for other features. (shrink)

Thinking is known to be state dependent but a systematic study of how thinking in dreams differs from thinking while awake has not been done. The study consisted of analyzing the dream reports of 26 subjects who, in addition to providing dream reports also provided answers to questions about their thinking within the dream. Our hypothesis was that thinking in dreams is not monolithic but has two distinct components, one that is similar to wake-state cognition, and another that is fundamentally (...) different. We found that cognition within a dream scenario was similar to that of wake-state cognition, but that thinking about the scenario itself was deficient and very different than wake-state thinking. (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)

This paper shows how the dream archive and search engine on DreamBank.net, a Web site containing over 22,000 dream reports, can be used to generate new findings on dream content, some of which raise interesting questions about the relationship between dreaming and various forms of waking thought. It begins with studies that draw dream reports from DreamBank.net for studies of social networks in dreams, and then demonstrates the usefulness of the search engine by employing word strings relating to religious and (...) sexual elements. Examples from two lengthy individual dream series are used to show how the dreams of one person can be studied for characters, activities, and emotions. A final example shows that accurate inferences about a person’s religious beliefs can be made on the basis of reading through dreams retrieved with a few keywords. The overall findings are similar to those in studies using traditional forms of content analysis. (shrink)

The similarities and differences in dream content at the cross-cultural, gender, and individual levels provide one starting point for carrying out studies that attempt to discover correspondences between dream content and various types of waking cognition. Hobson and Kahn’s. Dream content: Individual and generic aspects. Consciousness and Cognition, 16, 850–858.) conclusion that dream content may be more generic than most researchers realize, and that individual differences are less salient than usually thought, provides the occasion for a review of findings based (...) on the Hall and Van de Castle. The content analysis of dreams. New York: Appleton-Century-Crofts.) coding system for the study of dream content. Then new findings based on a computationally intensive randomization strategy are presented to show the minimum sample sizes needed to detect gender and individual differences in dream content. Generally speaking, sample sizes of 100–125 dream reports are needed because most dream elements appear in less than 50% of dream reports and the magnitude of the differences usually is not large. (shrink)