Self-reported effects of dreams on waking-life creativity: An empirical study

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Michael Schredl - Sleep laboratory, Central Institute of Mental Health, Mannheim, Germany
Daniel Erlacher - Institute for Sport and Sport Science, University of Heidelberg, Germany 

Bitte zitieren nach:
Schredl, M. & Erlacher, D. (2007). Self-reported effects of dreams on waking-life creativity:
An empirical study. Journal of Psychology, 141, 35-46.

Inhaltsverzeichnis

Abstract

Over the years, a variety of examples of how dreams inspire creative persons have been published. Nevertheless, empirical research in this area, in which “normal” people are investigated, is rather scarce. The present study focused on the self-rated effect of dreams on creativity in samples not selected for creative abilities. Within a student sample (N = 444) and a web-based survey sample (N = 636), a questionnaire about dreaming and creative dreaming was presented. In addition, the student sample completed several personality measures and creativity scales. The findings indicated that dreams which stimulated waking-life creativity played a considerable role in the everyday lives of ordinary people (about 8 % of all dreams). The examples reported by the Online Study participants fell into three categories: dream images used for art, work, or similar areas; dreams that solve a (most often) work-related problem, and dreams that provided the impetus to do something the dreamer otherwise had difficulties doing. The fourth category (emotional insights) was related to dreams within the psychotherapy domain. The main influencing factors on frequency of creative dreams were dream recall frequency itself and the “thin boundaries” personality dimension. Future research might focus on diary techniques to study the effects of dreams on subsequent waking life in a more detailed way and on the possibility of developing techniques to increase the frequency of creative dreams that might be valuable as aids for people in creative jobs.

Keywords: creativity, dreaming, dream recall

Introduction

A variety of examples of how dreams inspire creative persons are available in the published literature (cf. Barrett, 2001; Van de Castle, 1994). Well known, for example, are the surrealistic pictures of Salvador Dali who claimed that dreams stimulated his work. Similarly, filmmakers like Ingmar Bergmann (Wild strawberries), Carlos Saura, and Federico Fellini directly transformed their own dream images into film sequences. A famous example in literature is the The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson who had dreamed about this metamorphosis from one character into the other. Paul McCartney heard the melody of the hit “Yesterday” within a dream and could not believe it was a yet unknown song. These, of course, are anecdotal accounts that cannot be validated.

In addition to the creative dreams of artists, dreams contributed to problem solving in the area of science. The most often cited example may be Auguste von Kekule, who discovered the ring structure of the benzene molecule by thinking about a dream in which a snake seized hold of its own tail, although this report is subject to doubt since Kekule reported the dream long after its occurrence (for pros and cons see; Strunz, 1993). Other “dream solutions” have been reported for the categorization of the chemical elements (Dmitri Mendeleyev), the invention of the sewing machine (Elias Howe) and deciphering ancient Babylonian hieroglyphs (Herman V. Hilprecht; see Van de Castle, 1994). A third category comprises dreams that stimulate the dreamer to think and/or do something new in their waking life. A very impressive dream has been reported by William C. Dement, one of the pioneers of modern sleep and dream research (Dement, 1974). He was a heavy cigarette smoker and dreamed that he was diagnosed with inoperable cancer of the lung. He “experienced the incredible anguish of knowing my life was soon to end, that I would never see my children grow up ”(p. 102). He continues: “I will never forget the surprise, joy, and exquisite relief of waking up. I felt I was reborn. (p. 102),” and after this dream, he quit smoking.

Despite the many famous examples of the inspiring effects of dreams, empirical research in this area investigating “normal” people is rather scarce. Kuiken and Sikora (1993) and Schredl (2000) reported that 20 % and 28 % of their student samples, respectively, reported that they had dreams that gave them artistic ideas at least twice a year. Schredl (2000) found a strong relationship between frequency of creative dreams and dream recall frequency (r = .43; N = 85) and no gender differences in this variable – despite the well-known gender difference in dream recall frequency (for overview see: Schredl & Piel, 2003). Pagel, Kwiatkowski and Broyles (1999) studied individuals in creative roles (actors, screen writers, and editors). The group of film makers showed higher mean values than a control sample (general population recruited at a Family Practice Clinic) on a question, “Do your dreams affect your creative activities?”

Other studies have investigated the relationship between dreaming and creativity from the perspective of how creative persons differ in that respect from others. A review of the positive relationship between creativity and dream recall can be found in Schredl (1995). With regard to dream content, the finding of more bizarre dreams in creative individuals (e.g., Sladeczek & Domino, 1985) was challenged by Livingston and Levin (1991), who reported that this effect might be solely explained by dream length, i.e., creative persons report longer dreams which are more bizarre due to the length of the report. Whether consistent dream features can be associated with creativity in waking life is an open question for future research.

The present study focused on the self-reported effect of dreams on creativity in samples not selected for creative ability. The first aim was to determine how often creative dreams occurring in everyday life were reported. The second aim was to investigate influencing factors such as gender, personality traits, creative attitudes, and creative activities in waking life. It was expected that personality dimensions associated with openness to experience and measures of creativity would correlate positively with the occurrence of creativity-stimulating dreams. This hypothesis was derived from previous research indicating a strong relationship between these waking-life measures and a positive attitude towards dreams (e.g. Schredl, Wittmann, Ciric & Götz., 2003) and from the idea that a positive attitude is related to a higher probability to focus on the positive effects of dreams on waking life. Lastly, examples of creative dream effects were classified post hoc in order to give an impression of how dreams affect waking-life creativity.

Method

Participants

The first sample included 444 persons whose mean age was 23.5 years (SD = 5.7). These 376 women and 68 men were mainly psychology students. The participants were recruited at the Universities of Mannheim, Heidelberg, and Landau for a study entitled “Sleep, dreams, and personality”. Recruitment occurred by distributing lists during their classes. Participants were paid (40 DM) for participation.

The second sample included 636 persons who returned their questionnaire on lucid dreaming online (www.klartraum.de) between Jan 4, 2004 and Aug 5, 2004 and whose mean age was 25.5 years (SD = 9.8). Links on different psychology research and lucid dreaming sites were posted to inform prospective participants about the study. By eliciting the e-mail address of the participants, the possibility of multiple responding was minimized. In addition, the possibility that participants of the questionnaire study also completed the online study was very small because there was a 4 year time delay between the data collections. The mean ages differed between the samples (t = -3.8, p < .0001). The gender distribution was also different (second sample: 377 women and 259 men, 2 = 78.0, p < .0001).

Materials

Frequency of creative dreams and dream recall frequency

An eight-point rating scale to measure the frequency of creative dreams was presented within a self-developed dream questionnaire (“How often do your dreams give you creative ideas?” 0 = never, 1 = less then once a year, 2 = about once a year, 3 = about 2 to 4 times a year, 4 = about once a month, 5 = about 2 to 3 times a month, 6 = about once a week, 7 = several times a week). A similar eight-point scale (“How often do you experience nightmares?”) was utilized to measure nightmare frequency. Specific definitions for the terms “creative ideas” or “nightmares” were not given to the participants. In order to obtain units in frequency-per-month, the scales were recoded using the class means (0  0, 1  0.042, 2  0.083, 3  0.25, 4  1.0, 5  2.5, 6  4.0, 7  12.0). The recoded values of the scales (see below) were solely for descriptive purposes and were not entered into the statistical analysis.

Overall dream recall frequency was measured by a seven-point rating scale (0 = never, 1 = less than once a month, 2 = about once a month, 3 = twice or three times a month, 4 = about once a week, 5 = several times a week and 6 = almost every morning). The retest reliability of this scale for an average interval of 70 days is high (r = .83, N = 39; Schredl, 2002). In order to obtain units of mornings per week, the scale was recoded using the class means (0  0, 1  0.125, 2  0.25, 3  0.625, 4  1.0, 5  3.5, 6  6.5).

For the second sample, these three questions were included in an online questionnaire about lucid dreaming. Participants also were asked to report an example illustrating the creative effect of dreams they had had.

Personality measures

The German version of the NEO-PI-R (Ostendorf & Angleitner, 1994) comprises 240 five-point items (coded: 0 to 4) measuring the Big Five personality measures (neuroticism, extraversion, openness to experience, agreeableness and conscientiousness). Scale scores (with 48 items on each of 5 scales) can range from 0 to 192. The internal consistencies of the scales are high (r = .89 to 92), and confirmatory Multitrait-Multimethod analyses replicated the findings of the English version (Ostendorf & Angleitner, 1994).

The Absorption scale (Subscale of Tellegen and Atkinson’s personality inventory; Tellegen & Atkinson, 1974) consists of 34 Yes/No-items which measure the capacity of an individual to become absorptively involved in imaginative and aesthetic experience (e.g., “I can be greatly moved by eloquent or poetic language.”). Sum scores were computed. Since all absorption items were scored in one direction (Yes-answers), 32 unrelated items measuring other personality dimensions were included in the questionnaire (as done in previous studies: e.g., Belicki & Bowers, 1981). The internal consistency of the German version amounted to r = .85 (N = 51; Schredl, Jochum & Souguenet, 1997). The Boundary Questionnaire (Hartmann, 1991), which was translated into German by the Institute of Psychology, University of Zürich, Switzerland, includes 145 five-point scales covering 12 areas (e.g., sleep/dreams, unusual experiences, thought/feeling/mood, interpersonal relationships). The total score, reflective of boundary thinness, was derived by summing the ratings (ranging from 0 to 4) of 138 items, with item reversals when appropriate. Persons with “thin” boundaries are sensitive, creative and vulnerable, experience mental in-between states and involve themselves quickly in relationships. The internal consistency of the German scale was r = .93 (N = 152), the same as reported by Hartmann (1991) for the English version (r = .93, N = 966). For measuring visual imagination, a subtest of the “Erfassungssystem Veränderter Bewusstseinszustände” (Test battery for altered states of consciousness; Quekelberghe, Schreiber, Peter, and Caprano, 1992) was applied. The internal consistency of the 18 five-point items is high (r = .92; Quekelberghe et al., 1992).

Creativity Questionnaire

The scale assessing attitude towards creativity was developed by Schredl (1995) and contains 12 five-point Likert items. The mean of these items (which ranged from 1 to 5) was used in the analyses. The internal consistency was r = .67 (Schredl, 1995). In addition, the participants were asked whether they were engaged in creative activities, such as painting, playing an instrument, doing needlework/handicraft in their leisure time. Lastly, a five-point Likert scale (1 to 5) for the subjective estimate of one’s creativity was presented.

Design and Procedure

The participants of the first sample completed the questionnaires over a two-week period and returned them to one of the experimenters. Of 457 participants, 444 persons returned their materials. The participants of the second sample returned their questionnaire on lucid dreaming online (www.klartraum.de) between Jan 4, 2004 and Aug 5, 2004.

In addition to the materials described above, no additional information was obtained, e.g., applying screening instruments to rule out mental disorders or the taking of psychotropic medications; however, there was no reason to assume that normal students or web-based samples were nonrepresentative with regard to these characteristics.

Statistical analyses were carried out with the SAS 8.02 software package for Windows. Since the self-developed scales were ordinal, Spearman-Rank correlations were computed.

Results

Frequency of creative dreams, dream recall frequency and nightmare frequency

In Table 1, mean values and standard deviations of the three frequency scales are depicted. The statistical analyses (ANCOVA with ‘Study’ and gender as independent variables and with age as a covariate) revealed no significant differences between the two studies (Questionnaire and Online Study): dream recall frequency (F(1, 1069) = 2.8, p = .10), nightmare frequency (F(1, 1068) = 0.2, p = .66), and frequency of creative dreams (F(1, 1068) = 2.6, p = .11).


Table 1. Dream variables for the two samples.

Variables Questionnaire Study Online Study
Women Men Women Men
M SD M SD M SD M SD
Dream recall frequency (seven-point scale: 0 to 6) 4,49 1,16 4,16 1,31 4,69 1,33 4,31 1,67
Nightmare frequency (eight-point scale: 0 to 7) 3,66 1,65 2,97 1,73 3,79 2,00 2,68 2,00
Frequency of creative dreams (eight-point scale: 0 to 7) 2,12 1,65 2,15 1,57 2,40 2,32 2,44 2,35


Small but significant gender differences were found for dream recall frequency (F(1, 1069) = 10.2, p < .01) and nightmare frequency (F(1, 1068) = 43.3, p < .0001), but not for frequency of creative dreams (F(1, 1068) = 0.0, p = .88). A slight decline with age was present for dream recall frequency (F(1, 1069) = 4.3, p < .05), this age decline was more pronounced for nightmare frequency (F(1, 1068) = 22.1, p < .0001). No significant interactions were found between study effect and gender. At least one creative dream was reported by 71.4 % of both samples. About 45.1 % of the individuals estimated a frequency over twice a year and almost 9 % of the participants reported effects on their creativity once a week or more often. Transforming the scale values into their absolute frequencies (see method section) yielded a mean dream recall frequency of 3.11 mornings per week (SD = 2.32), and a mean frequency of 1.05 dreams stimulating waking-life creativity per month (SD = 2.47). The quotient was 7.8 %; providing a rough estimate about the percentage of creative dreams in relation to all recalled dreams.

Frequency of creative dreams, dream recall frequency, and correlations with personality and creativity measures

Dream recall frequency was significantly related to frequency of creative dreams (r = .29, N = 1075, p < .0001). In Table 2, the Spearman Rank correlations are depicted for the frequency of creative dreams, and dream recall frequency with creativity and personality in the Questionnaire Study. Whereas the correlation coefficients between the waking life measures and dream recall frequency have previously been rather low (for detailed analysis and a structural equation model see: Schredl et al., 2003), all variables expected to correlate, including openness to experience, boundary thinness, imagination, absorption, attitude towards creativity and creative activities, were related to frequency of creative dreams (with the medium effect size of r = 0.3 for most variables). All these coefficients were significantly higher than the corresponding coefficients for dream recall frequency, i.e., the relationship between these waking life measures and frequency of creative dreams is much closer and cannot be explained by dream recall frequency as a possible mediator variable. As expected, of the Big Five Factors, only the openness of experience factor was related to frequency to creative dreams.


Table 2. Frequency of creative dreams, dream recall frequency, personality measures and creativity (Questionnaire study).

Personality dimensions Internal consitency 2 Questionnaire Study Correlation with Creative dreaming Correlation with Dream recall Comparison of correlation coefficients
M SD r; p r; p z; p
Neuroticism 0,93 99,50 23,70 .024; .62 .039; .41 -0.3; .79
Extraversion 0,90 112,60 19,80 .061; .20 .009; .84 0.9; .35
Openness to experience 1 0,86 129,80 15,70 .268; <.0001 .133; <.01 2.5; <.01
Agreeableness 0,86 113,40 15,80 .041; .39 -.083; .08 2.2; <.05
Conscientiousness 0,90 109,00 19,10 .027; .57 .015; .76 0.2; .83
Thin boundaries 1 0,92 289,70 43,20 .381; <.0001 .141; <.01 4.6; <.0001
Absorption 1 0,83 21,60 5,70 .370; <.0001 .126; <.01 4.6; <.0001
Imagination 1 0,85 51,00 10,80 .319; <.0001 .165; <.001 2.9; <.001
Attitude towards creativity 1 0,76 3,51 0,59 .300; <.0001 .035; .23 4.9; <.0001
Self-rating of creativity 1 - 3,68 1,05 .291; <.0001 .033; .24 4.8; <.0001
Painting 1 - 49.5 % .227; <.0001 .105; <.05 2.2; <.05
Playing music 1 - 15.8 % .121; <.001 -.022; .68 2.6; <.01
Needlework/handicraft 1 - 28.9 % .161; <.001 .036; .22 2.3; <.05

Note. 1 one-tailed statistical tests for correlation coefficients; 2 internal consistencies of the scales computed for the present sample (Cronbach’s alpha)


An exploratory regression analysis examined frequency of creative dreams as the dependent variable with simultaneous entry of all hypothesized variables (see Table 2). As depicted in Table 3, the following significant variables were identified in terms of their importance: dream recall frequency, boundary thinness, imagination and attitude towards creativity. The other variables such as creative activities, openness to experience were not significantly related to the frequency of creative dreams in the regression analysis (due to their intercorrelations with the other variables).


Table 3. Summary of regression analysis for variables predicting frequency of creative dreams.

Variable B SE B ß
Dream recall frequency 0.35 0.06 0.26***
Openness to experience -0.01 0.01 -0.08
Imagination 0.02 0.01 0.11*
Boundary thinness 0.01 0.00 0.25***
Attitude towards creativity 0.37 0.17 0.13*
Self-rating of creativity 0.12 0.10 0.08
Painting 0.18 0.16 0.06
Playing music 0.30 0.19 0.07
Needlework/handicraft 0.22 0.16 0.06

Note. R2 (adj.) = .27; *p < .05. ***p < .0001.


Content of creative dreams

In Table 4, the examples of creative dreams reported within the Online Study have been classified post hoc into the three groups mentioned in the introduction: dream with direct impulses for art work, problem solving dreams, and dreams that stimulate a specific behavior in waking life. These categories will be illustrated by examples (see below). A fourth category contained dreams with emotional insights.

  • Example 1 – Creativity (Painting): Within the dream I saw a mermaid which transformed into a butterfly. This image served as a basis for a pastel painting.
  • Example 2 – Creativity (Writing): I often dream that I can fly. This gave me the idea of writing a book on a man who can really fly. He flies to look for his beloved one and causes fear and terror among the people.
  • Example 3 – Creativity (Other): Shortly before the birthday of my mother, I once dreamed of something that would make a wonderful gift. Within the dream I saw exactly her reaction to the present. I then actually bought this present and, indeed, she was just as happy about it as was depicted within the dream.
  • Example 4 – Problem solving: My personal computer was broken, and I dreamed about how I could fix it in the best way. I woke up in the morning, and it was clear to me how get things going.
  • Example 5 – Problem solving: Within a dream an error in a computational formula of my master thesis came to my mind, which I was able to resolve in the dream by creating a new formula.
  • Example 6 – Dreams as impulses: I dreamed of a girl from my school, on whom I had a crush. This dream motivated me to approach her.
  • Example 7 – Dreams as impulses: I have dreamed that I was on a theater stage. I was alone on the stage, no audience was there. I sang and heard applause without seeing the listeners. On basis of this dream, I decided to take voice lessons.
  • Example 8 – Emotional insight: I was sitting in a railway compartment, with a handbag on my lap that opened unintentionally, and everything fell out. A man was willing to help me put the things back, but there were so many utensils that everything fell out again. Afterwards I decided to examine carefully what kind of things or thoughts I should part with, i.e., simplifying my life.


Table 4. Themes of the creative effect of dreams on waking life (N = 272 responses).

Themes Absolute Frequency
Creativity
- Painting 30
- Literature/Writing 25
- Music 5
- Other (Web design, recipes, gifts) 24
Problem solving
- Work-related, thesis, lectures 49
- Computer 11
- Mathematics 11
- Motor Skills 4
Dream as impulse
- Approaching someone, relationships, travelling etc 73
New emotional insights within the dream 40


Discussion

Overall, the findings of this study clearly indicated that a considerable number of ordinary people reported dreams which stimulated creativity in everyday life. A rough estimate revealed that about 8 % of the dreams affected creativity. This causal claim was solely based on the participants’ estimates. Unfortunately it is not possible to use experimental paradigms to validate such claims, since dream content cannot be manipulated without conscious knowledge of the person that could also possibly affect subsequent waking-life experiences such as creative ideas. Although the questionnaire did not include a explicit definition of the “creative idea” term within the frequency item, all examples given by the participants of the online study fit in the categories of creative dreams (see Table 4), i.e., problems of understanding the concept of creative ideas as an effect of dreams must have been negligible.

The examples reported by the Online Study participants were divided into the three categories introduced in the beginning in order to give an overview of different creative dreams topics. Individuals used dream images for art work or similar areas. They reported dreams that solved (most often) work-related problems and dreams which gave an impetus to do something they otherwise had difficulties doing. The question of whether this categorization of creative dreams fits in a conceptual framework of creativity will be an interesting question for future research. The fourth category of emotional insights was related to the topic of dreams within psychotherapy (see Schredl et al., 2000) and personal growth. Hill (2004) has been able to demonstrate empirically how effective dream-work in both contexts can be, and in addition, there exists a large literature on dream interpretation or dream-work. This study investigated the self-reported positive effects of dreams on subsequent waking life, but one should keep in mind that dreams, especially nightmares, can be disturbing and affect the well-being of the day afterwards (for a detailed study see: Köthe & Pietrowsky, 2001).

Taking the effects of dreams on waking life together with the effects of waking life on subsequent dreams, i.e. the so-called continuity hypothesis of dreaming (Schredl, 2003), one might hypothesize that there is a stream of consciousness which is always active, day and night as waking thoughts/feeling and as dreaming.

From a methodological viewpoint, it was interesting to see that in comparisons controlling for gender and age there were no differences between the Online Study and the Questionnaire Study. A major limitation of the present study was its retrospective nature. To complement the present findings, it will be very promising to use dream diaries in which participants write down their dreams and their dream effects immediately after their occurrence.

Regarding the influencing factors affecting frequency of creative dreams, the present findings did not find differences between the sexes (cf. Schredl, Bohusch, Kahl, Mader, and Somesan, 2000), although a small gender difference for dream recall frequency was detected. Given that dream recall frequency is strongly related to the frequency of creative dreams, this result seems difficult to explain on the basis of the present data.

Interestingly, personality factors, attitude towards creativity, and creative activities were more closely related to the frequency of creative dreams than to dream recall frequency. On the basis of the life-style hypothesis of dream recall (overview: Schredl, 1999), one might have expected a stronger relationship between creativity and dream recall frequency as it has been reported by previous studies (Schredl, 1995). On the other hand, Schredl et al. (2003) showed that a positive attitude towards dreams was also more closely related to personality factors that dream recall frequency itself. This might be interpreted in a way that dream recall frequency, i.e., the probability of recalling a dream in the morning, depends on a large variety of factors (memory, sleep parameters, personality, stress etc.), and thus, the variance explained by personality dimensions is quite small. In contrast, attitude towards dreams and frequency of creative dreaming are largely determined by personality factors and – in the case of creative dreaming – by the amount of creative activities in waking life. In short, the life-style hypothesis may apply only to these aspects of dreaming rather than to dream recall frequency itself.

The exploratory regression analysis, which was carried out to take the intercorrelations between the variables into account, revealed that the most important factor explaining differences in frequency of creative dreams was dream recall frequency. This outcome made sense, since the probability of having a creative dream increased with the number of dreams recalled. However, several personality dimensions (thin boundaries, imagination and positive attitude towards creativity) also were correlated with frequency of creative dreams. These data fit in with the description of persons with thin boundaries as being creative and unconventional (Hartmann, 1991). To carry this kind of research further, it would be interesting to study whether it is possible to increase the frequency of creative dreams by – for example – increasing dream recall frequency (see Schredl, 1999) or through special recommendations to tap the creative power of dreams (e.g., Tonay, 1995).

To summarize, the present study demonstrated that ordinary individuals reported that dreams stimulated waking-life creativity. The main influencing factors were dream recall frequency itself and the personality dimension “thin boundaries.” Future research might focus on diary techniques to study the effects of dreams on subsequent waking life in a more detailed way. Those studies might also develop techniques to increase the frequency of creative dreams, which would be a valuable aid for people in creative lines of work. Given the findings of this study, the first step would be to apply such techniques as keeping a dream journal, and using pre-sleep suggestion about successful recall to increase overall dream recall frequency. Also, in accordance with the continuity hypothesis of dreaming, specifically designed creative tasks carried out in the evening should result in dreams with content associated with creativity.

Acknowledgments

The data collection of the first sample was supported by a grant (SCHR 637/2-1) from the Deutsche Forschungsgemeinschaft (DFG) given to the first author.

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