Frequency and categorization of presleep fantasies

Abstract

The content of presleep thoughts have been assumed to influence sleep quality for a long time, e.g., insomnia has repeatedly been discussed to be associated with anxious thoughts before falling asleep. However, the phenomenon of recurring, voluntary fantasizing before sleep does not appear to be a common research topic. In the first stage of this study, we explored the frequency of presleep fantasizing on a sample of 281 volunteers. In the second stage, we analyzed the content of ca. 5000 fantasy descriptions found online to discover similar patterns. Our results showed that approximately 75% of the respondents fantasizes before sleep regularly and could describe three main topics during categorization (‘aims and ambitions’, thinking about a ‘calming’ scene, ‘fading away and death’). Based on our findings, presleep fantasizing is a common phenomenon. To our knowledge, this is the first study to investigate and categorize presleep fantasies.

Full text

Frequency and categorization of
presleep fantasies
Anna Szente1, Husamalddin Ali Alhour1, Eszter Áfra2, Ákos Arató1,2, Barnabás Dudás1,
AnnaSzűcs3, Réka Horváth1, Norbert Kovács1, Gergely Darnai1,2,4 & József Janszky1,4
Thecontentofpresleepthoughtshavebeenassumedtoinuencesleepqualityforalongtime,
e.g., insomnia has repeatedly been discussed to be associated with anxious thoughts before falling
asleep. However, the phenomenon of recurring, voluntary fantasizing before sleep does not appear
tobeacommonresearchtopic.Intherststageofthisstudy,weexploredthefrequencyofpresleep
fantasizingonasampleof281volunteers.Inthesecondstage,weanalyzedthecontentofca.5000
fantasy descriptions found online to discover similar patterns. Our results showed that approximately
75%oftherespondentsfantasizesbeforesleepregularlyandcoulddescribethreemaintopicsduring
categorization (‘aims and ambitions’, thinking about a ‘calming’ scene, ‘fading away and death’).
Basedonourndings,presleepfantasizingisacommonphenomenon.Toourknowledge,thisisthe
rststudytoinvestigateandcategorizepresleepfantasies.
Keywords Sleep, Fantasy, Presleep fantasy, Presleep period
Cognitive activity during the presleep period has been suggested to inuence sleep quality and thus the
contribution to insomnia for a long time1, however, the content of presleep thoughts remains on the periphery
of this research eld2,3. e shi of attention from the external world to our inner thoughts is something that we
experience regularly, most of us tend to spend 50% of our time during the day with task-unrelated thoughts4.
Fantasizing and being occupied with our own personal thoughts are oen introduced as a failure of executive
control5, therefore many disadvantages can be highlighted like sleep diculties6, worse performance and
daytime functioning7. On the contrary, there is a more positive apprehension of the phenomenon. Because it is
so common, some studies have suggested that it has a valuable function: depending on the associated feelings,
fantasizing could contribute to attentional uctuations, dishabituation (when a break from an ongoing task allows
to enhance learning potential), thinking through future plans and enhanced creativity8. In this sense, while some
studies consider it to be an interruption of an ongoing task, there is growing evidence showing that fantasizing
facilitates adaption9 and can contribute to self-development. In summary, while fantasizing has been seen as
both a cost and a benet10, its function and value remain unclear. One possible explanation is that when a certain
task or goal is considered too limited, the mind starts to explore something more advantageous11. However, it
has also been suggested, that it would be important to distinguish between intentional and unintentional forms
of this phenomenon12.
During the period of falling asleep, the perception of external stimuli is steadily reduced, allowing for voluntary
presleep fantasizing. We can nd two types of task-unrelated thoughts, based on whether the attentional shi is
consciously or unconsciously controlled, presleep fantasizing can take the conscious form, attention deliberately
shis from the external to the internal world13. Why this phase could be meaningful in sleep research is shown
by the many aspects sleep is linked to emotions. Stress can alter sleep through sleep fragmentation and increased
sleep latency14. An other study showed, that a negative feedback provided on a test to participants, resulted
in deteriorated sleep quality15. ese results pointed to the extent of how emotions play a role in determining
sleep aspects in otherwise healthy individuals. e connection is bidirectional: decreased sleep eciency alters
emotion regulation as well16. Although studies agree that there is a link between presleep cognitive activity and
sleep quality, it is hard to compare the results of these studies due to the absence of presleep fantasies’ content
descriptions17.
e power of presleep thoughts, and their inuence on sleep quality is well known, mostly related to negative
consequences: ruminative and anxious thoughts may contribute to poorer sleep quality18, repetitive thoughts of
stressful events may lead to elevated arousal, delayed sleep onset and thus diminishing sleep19. On the other hand,
the nature of presleep thoughts could be inuenced to improve sleep quality, for example by listening to relaxing
1Department of Neurology, Medical School, University of Pécs, Pécs, Hungary. 2Department of Behavioral
Sciences, Medical School, University of Pécs, Pécs, Hungary. 3Department of Behavioral Sciences, Medical School,
Semmelweis University, Budapest, Hungary. 4HUN-REN PTE Clinical Neuroscience MR Research Group, Pécs,
Hungary. email: darnai.gergely@pte.hu
OPEN
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words before sleep: the processing of relaxing words could activate several other brain regions contributing to
calmness20. us, we hypothesized, that a dierent character of conscious, voluntary fantasizing would help
the transition to sleep. To analyze the content of presleep fantasies, we examined online platforms dedicated to
sharing such information. In an article posted on Buzzfeed on the 14th of November, 2017., titled “34 Pre-Sleep
Fantasies at Will Make You Say “I thought I Was e Only One”” ( h t t p s : / / w w w . b u z z f e e d . c o m / a n n a b o r g e s / b e
f o r e - b e d - f a n t a s i e s ) , the author, Anna Borges asked the community to post these fantasies. e content of these
fantasies was e.g., relationship, prize winning, or fantasies inspired by movies or celebs. Online platforms may
help discover a wider range of presleep thoughts: anonymity encourages users to share sensitive information
about themselves compared to the identiable users21. In this study, our aim was to discover the prevalence of
fantasizing before falling asleep and analyzing the content of these fantasies, for similar patterns to be uncovered.
In the rst stage, with an online questionnaire, we asked about the frequency of presleep fantasizing, in the
second stage, we collected descriptions of presleep fantasies online.
Methods
Study I
In study I, we assembled a questionnaire package as an assessment of sleep quality and the occurrence of presleep
fantasies. e questionnaire package contained two questionnaires (short version of Pittsburgh Sleep Quality
Index - PSQI & Glasgow Content of oughts Inventory - GCTI) and two extra questions about fantasizing and
creating stories in the presleep period.
e survey was assembled in Google Forms and shared on social media platforms, on Facebook. Participants
were instructed to read the items carefully and answer the rst thing that come to their minds. ey were informed
that all of their answers would remain anonymous. Additionally, we asked three questions on demographics
(age, gender, education). e answers were collected from the 1st of March to the 25th of March 2021.
Participants
Our questionnaire package was accessible through an online link and 281 participants (243 females and 38 males)
completed the questionnaire form. e mean age was 33.91 years (SD = 13.14). According to the education,
participants were classied as: 37% Master’s Degree, 19.5% Bachelor’s Degree, 32% High School Graduate and
11.5% less than High School.
During this study, all methods were carried out in accordance with relevant guidelines and regulations. Based
on the ocial statement of the Regional Research Ethics Committee of the University of Pécs (9861 – PTE 2024)
an Ethical Approval was not necessary for this study. Using this questionnaire was considered safe, as all data
were collected anonymously. With completing the online questionnaire, applicants voluntarily took part in this
study, and an informed consent was obtained from all participants.
Pittsburgh sleep quality index (PSQI)
To measure subjective sleep quality over a one-month period, we used the Hungarian version of PSQI22. PSQI is
a widely accepted, self-rated questionnaire, which contains 19 self-reported items and 5 questions to be answered
by roommate or bed partner. e global score consists of seven components: perceived sleep quality, sleep
latency, sleep duration, sleep eciency, sleep disturbances, hypnotic medication use and daytime dysfunction.
According to our interest we removed a few components: hypnotic medication use, daytime dysfunction and
rating of bed partner/roommate, since these questions refer to the clinical aspects of sleep diculties. Although
daytime dysfunction and hypnotic medication use supposedly interfere with presleep cognitive activity, in this
study, our interest was mainly focused on the other characteristics of sleep. Each component score was calculated
from the item scores that range from zero to three (0 = no problem, 3 = severe problem).
Glasgow content of thoughts inventory (GCTI)
e 25-item self-report GCTI contains categories of presleep thoughts, which were collected from insomniac
subjects to analyze the nature and intrusiveness of their thoughts. e questionnaire items represent these
thoughts that insomniac people tend to revolve around prior to sleep. Every item should be answered on a
4-point scale (0 = never, 1 = sometimes, 3 = oen, 4 = always)23. In the lack of the validated Hungarian version,
the original GCTI was translated into Hungarian by our research team. Two extra questions were added as item
26 and item 27, reecting to presleep fantasizing and creating stories (“In the past 7 days before sleep I was
preoccupied with fantasizing”, “In the past 7 days before sleep I was preoccupied with creating stories”). Listing
both of them might help discover dierent aspects of the presleep cognitive activity. Although these questions
were listed at the end of the GCTI questionnaire, we would not include them as questionnaire scores, they were
used to indicate the frequency of fantasizing and creating stories. To get a broader picture of presleep thoughts,
two sets of the GCTI questionnaire were used indicating presleep thoughts of the past week and the past ten
years.
Statistical analysis
To perform statistical analysis, we used IBM SPSS Statistics 25 soware (IBM Corp. Released 2017. IBM SPSS
Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp). Descriptive statistics were used to analyse
demographical data, the mean and standard deviations were calculated. For the correlational analysis, Spearman’s
correlation was used.
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Study II
e purpose of Study II was to analyze presleep fantasies shared in online forums and categorize them according
to their contents. To our best knowledge, to date, no other study has found intersubject similarities regarding the
content and motives in presleep thoughts.
e following search terms were used in Google search: “presleep fantasy”, “presleep thoughts”, “go-to fantasy”,
“falling asleep fantasy”, “presleep period”. For the purpose of the analysis, we selected two online forums. Most of
the reports were found on a Reddit forum, entitled “What is your go-to fantasy you think of before falling asleep”
(https://www. reddit.com/r /AskReddit/c omments/8z1 57b/what_is_your_goto_fantasy_you_think_of_before/).
About 9500 reports were within this range. Since many of them were not related to the original question, a
screening procedure was applied to remove unrelated reports. erefore, 5090 fantasies remained in our data
base. We also ignored those reports that were not considered a fantasy, such as planning the next day or a learnt
method to help the transition to sleep, thus 4912 reports remained.
Another forum, titled “Do you ever create fantasy stories in your head before you go to sleep?” ( h t t p s : / / f o r u
m s . d i g i t a l s p y . c o m / d i s c u s s i o n / 1 8 2 9 6 7 8 / d o - y o u - e v e r - c r e a t e - f a n t a s y - s t o r i e s - i n - y o u r - h e a d - b e f o r e - y o u - g o - t o - s l e e
p ) involved 22 comments.
Based on the reports of the abovementioned forums, the category system consisted of three main parts: (1)
content-based categories, that were established during several meetings with our research team. Based on this,
classication of each fantasy report was decided by two of the authors (ASZ and HAA), and inconsistencies, which
occurred in 4% of all cases, were decided by a third independent investigator (EÁ), (2) commonly occurring
words to detail the fantasy, that were selected by our team aer reading through the fantasy descriptions carefully,
and their occurrence was calculated using Excel spreadsheets and (3) analyzing the following characteristics:
reality of the fantasy; presence of sensory modalities, memories; features of movies, series, books, videogames;
temporal aspects: fantasy evolving over time or existing in the past only; playing a main or minor role and being
lonely or having company in the fantasy.
e nal collection of presleep fantasies contained 4934 reports using the two forums mentioned above.
We assumed that commonalities of presleep fantasy content would occur which could provide the base to
classication.
Data used in this study was collected from publicly available online platforms. For the protection of user
privacy, our results did not contain any identiable information about the users, and we have complied with the
relevant terms and conditions of these platforms. Due to the use of anonymized, publicly available data, and the
position of Reddit, that collection of data is not prohibited for academic purposes only (i.e. non-commercial), an
ethical approval was not necessary, supported by the statement of the Regional Research Ethics Committee of the
University of Pécs (9861 – PTE 2024). Previous studies analyzing online data have followed a similar approach.
Results
Study I
Pittsburgh sleep quality index and glasgow content of thoughts inventory
e mean score of the PSQI questionnaire was 4.199 ± 2.241. Values ranged between 1 and 12. A higher global
score indicated poorer sleep quality.
GCTI was listed twice in the questionnaire package presenting the past seven days and the past ten years,
respectively. A ten-year period was chosen subjectively, since we assumed this could indicate a relevant picture
of sleep habits in the past. e mean score for GCTI showing the past seven days was 25.99 ± 12.25. Values
ranged between 0 and 65. Based on the 42-point cut-o, by the GCTI, 24 people t into the poor sleepers group.
Regarding the past 10 years, results seemed similar with 31 individuals in the poor sleepers’ group, mean score
was 28.61 ± 11.77.
Fantasizing/creating stories before sleep
Percentages of the extra two questions, respondents reporting fantasizing/creating stories before sleep are
presented in Table1. e majority of the respondents experienced presleep fantasizing on a regular basis.
Although it is questionable whether our participants could provide a reliable answer of the past 10 years, we
could not exclude the possibility, that we would gain valuable information. According to the results of the past
10 years, they were very similar to the percentages and GCTI scores listed above, therefore we can assume that
frequency of fantasizing and creating stories did not change too much during the years.
Spearman correlation analysis
PSQI, GCTI questionnaire scores and fantasizing/creating stories were correlated. e correlation between
GCTI and fantasizing/creating stories was signicant and correlated positively (R = 0.321, p<0.001; R = 0.304,
Fantasizing Creating stories
Always 12.4% (12.5%) 9.6% (9.9%)
Oen 21.7% (23.4%) 12.8% (16.5%)
Sometimes 38.8% (39.1%) 23.5% (27.8%)
Never 27.1% (25.0%) 54.1% (45.8%)
Tab le 1. Prevalence of fantasizing/creating stories during the past 7 days and 10 years. Note. Percentages
inside parenthesis refers to the frequency of fantasizing in the last 10 years.
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p<0.001), suggesting that a higher GCTI score coincides with a higher occurrence of presleep fantasizing and
creating stories. ere was no association between fantasizing/creating stories and PSQI scores.
Study II
Content based category system
Based on content, four main categories and several subcategories (25 in total) were established. Main categories
were”: ‘aims and ambitions’, thinking about a ‘calming’ scene, ‘fading away and death’ and if the fantasy did not
t into any of these sections (mostly due to the absence of further details), an ‘other’ category was created. First,
two authors (ASZ and HAA) inserted the fantasy reports in the category system. Aer merging, in the resulting
two tables, 4% of all the categorization results were varying. Upon discussion, the dierences aected poorly
detailed fantasy reports, and their nal category was decided by a third, independent author (EÁ). Distribution
of the main categories is shown in Table2.
Majority of the presleep fantasies belonged to the category ‘aims and ambitions’. People shared more or less
ctitious wishes and goals like having superpowers, being another character, being able to change the past,
monetary reward, love and relationships, sexual fantasy, being successful or meeting celebrities. Contrary to
the calming fantasies, respondents here oen detailed an exciting, developing storyline. is category mostly
involved stories based on positive emotions, but a smaller part of them were negative, anxious or unpleasant
fantasies. Some of the reports were not straightforward and not clear enough to understand the content, therefore
we included them to more than one category, due to a possible overlap. Table3. presents the list of subcategories,
the prevalence and examples of the reports of ‘aims and ambitions’ category.
e second most frequent category was imaging a calming, relaxing situation. A calming situation appearing
in the fantasy indicated an undisturbed, peaceful scene mainly associated with loneliness. It appeared in dierent
forms, depending on whether it took place in an open (e.g. forest) or closed (e.g. cave) space, or involved a
relaxation technique („I usually imagine with every exhale I’m sinking into the ground more and more and I feel
myself becoming a part of the earth.”). Table4. shows subcategories within the calming situations.
Based on commonalities, these categories could be divided into further sections: some respondents placed
the relaxing fantasy in a post-apocalyptic situation, representing complete isolation (e.g., “Zombie outbreak
starts and I gather the family and meet my loved ones at the bunker/armory.”). We created a subcategory, where
loneliness is especially noted: ‘last person on Earth’ with the extinction of all other humans on the planet (e.g.,
“I would the last person on earth and hop on any car id like and drive alone on the freeways for hours at a time
and have some fun alone.”). If the fantasy took place somewhere closed, it represented not only calmness but also
safety (e.g., „My go-to fantasy for some reason has always been just me sipping on hot chocolate late at night in
Category Frequency Example
Being someone else
Love, relationship 1108
546 “It’s okay. My fantasy is being Tony Stark.”
“So true it hurts. I imagine my ideal relationship”
Specic wish 495 “Playing football for my favorite team.”
Superpower 473 “Sometimes what I would do if I had superpowers”
Desires in general 408 “Being happy”
Sexual fantasy 259 “Porn. e acting is mind numbing which actually helps me fall asleep.”
Receiving an award or monetary reward 230 “Winning the lottery!”
Accomplishment, success 197 “Being an NBA player”
Aggression, violence 191 “I fantasize of me beating some annoying youngster to oblivion.”
Negative, unpleasant situation 145 “Getting rejected by everyone I like”
Meeting celebrities 78 “Usually, some kind of relationship involving my celebrity crush of the day.”
Being able to change the past 80 “at I will wake up the next morning ten years old again in 1993 with all of the knowledge I currently have.”
Powerful, inuential position 71 “Being a God in another world. I love being a god.”
Plans for the future 58 “What the house my future family and I have will look like; I imagine it being very cozy!”
Freezing the moment 35 “I like to imagine all people on earth get paused, except for me. en, I go explore.”
People reacting to the narrator’s funeral 21 “How would people react if I died.”
Meeting deceased people 14 “Seeing my dad one last time….”
Tab le 3. Subcategories of category aims and ambitions, prevalence and examples.
Category Number of presleep fantasies
Aims and ambitions 4409
Calming fantasies 1039
Fading away and death 174
Others 382
Tab le 2. Main categories of presleep thoughts based on content.
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the O’Hare International Airport all alone. Usually, I think of soothing jazz music playing too.”), and it involved
a class where a danger source also occurred (Fig.1). Origin of the danger appeared in dierent forms: it could
be a raging thunderstorm, dinosaurs, the space or a stormy sea. Manifestation of safety varied too: it appeared to
be a cave, tent, space pod or submarine (e.g., “e veranda on a log cabin in the forest, by a lake. It’s raining. We
have an outdoor heater burning, wrapped in blankets.”).
A less frequent, but separable topic included death-related thoughts and fading away. ese fantasies were
mostly short, straightforward thoughts, or could be more complex fantasies (e.g.,” (…) I just get this creeping
cold down my spine and feel like death and think about how when we die there is nothing and everything is
worthless and then I snap back to reality, and either do it again or pass out”). Interestingly, some of these death-
related thoughts were not associated with negative feelings, but with peaceful ones (“I dream of a small asteroid
the size of a bus speeding towards earth. it loses most of its size in the atmosphere and when its hits earth, it
hits exactly me and only me. Everything I own and was eradicated in an instant and I felt nothing. e thought
calms me.”).
If none of the categories mentioned above were suitable for the presleep thoughts, we put them into an ’other’
category. Most of these reports were too shortly dened to be understood (“Dogs. Literally just dogs or ants.”).
List of commonly occurring words describing presleep fantasies
Besides the categories, we also calculated the occurrence of a few selected words to describe a fantasy content.
We selected words which are aligned with the content-based category system. erefore, we reviewed the context
of the inspected word, and removed it if the respondent did not use it in a certain meaning (e.g., ‘space’ can
describe a location, that can be indenite and the cosmic space too, which we were looking for). ‘Space’ was the
most frequently occurring word, mostly to explain a relaxing, isolated situation far from everyone else. ‘Hero’
was also used commonly to express ambitions such as playing the main role in a heroic action, being able to get
revenge or constructing an exciting storyline (“Being a Robin Hood type anti-hero in a superhero story where
I save the world by robbing banks. It’s kinda lame but it’s fun to imagine.”). e word ‘y’ appeared in dierent
Fig. 1. Schematic presentation of subcategory ‘outside danger’ belonging to the rst-order category, ‘calming
fantasies’. Note: is gure demonstrates examples of danger sources and safe place choices within the
subcategory ‘outside danger’.
Category Number of presleep fantasies
Open space 313
Relaxation 189
Isolation 175
Outside danger 162
Post apocalypse 110
Closed space 43
Survival 28
Last person on Earth 19
Tab le 4. Subcategories of calming presleep fantasies.
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forms. It could be a part of a relaxing (e.g., “at my bed is ying through the night sky. As I dri closer and
closer into sleep, I can actually start feeling the sensation of weightlessness and propulsion underneath me, it’s
pretty awesome: )”) or a more thrilling fantasy (e.g. “For my entire life, I’ve always gone to sleep with the thought
of being able to y, swooping down and saving people from danger superman-style…”). Table5. presents the
most frequently occurring words.
Category system based on commonalities
An additional thematic analysis was conducted to isolate the most common traits of fantasy reports as well: (1)
whether the content could be real or ctional (2) sensory modalities involved (3) fantasy based on memories (4)
fantasy based on movies, series, books or videogames (5) fantasy evolving over time (6) fantasy takes place in the
company of others (7) whether the person describing the fantasy played the main role (Table6).
Discussion
Presleep fantasizing might be a conscious eort to facilitate the process of falling asleep and a part of a normal
routine. However, it has not been systematically investigated before, particularly, the content of those fantasies.
Category Number of presleep fantasies Description
Real 2458 Parts of the fantasy could occur in the real world.
Fictional 2309 Details of the fantasy could only happen in an imaginary world.
Sensory modalities ere are senses mentioned within the description of the fantasy.
1. Sound 58 Noises are highlighted in fantasy descriptions, usually linked to a peaceful
scene.
2. Touch 130 Respondents imagine something aecting their body.
3. Smell 12 Smells are appearing in the fantasy.
Based on memories 81 Important components of the fantasy are memories, oen from childhood.
Based on movies, series, books or videogames 816 Structure of the imaginary scene is taken from an existing story.
Fantasy evolves over time 315 Presleep fantasizing have been present for several years and respondents
add further details to their fantasy.
Used to fantasize 66 Respondents usually remember presleep fantasies that are not present
anymore.
Loneliness 639 Presleep fantasy revolves around only the respondent.
Company 1655 Other people are involved in the fantasy as well.
Main role 4710 Respondent is the central gure of the narrative.
Not part of the fantasy 119 Describer is not part of the fantasy storyline.
Tab le 6. Classication system of presleep fantasies based on commonalities.
Word Prevalence
Space 172
Hero 137
Fly 133
Lotto/lottery 129
Apocalyp’ 112
Kill 104
Ship 102
Zombie 101
Surviving/survival 96
Forest 74
Planet 74
Dark 68
Mountain 63
Alone 63
Beach 60
Rain 57
Tow n 54
Island 53
Tab le 5. Prevalence of the most commonly used words to describe presleep fantasies.
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In these two studies our aim was to investigate presleep fantasizing. In the rst study, we assessed the
occurrence of fantasizing before sleep in a sample of 281 participants. We found that approximately 75% of
our sample fantasized or created stories before sleep regularly. Similar results were found in a study of more
than 500 individuals, examining the link between cultural beliefs and sleep, where approximately 75% reported
daydreaming before sleep, which was also found to be linked with longer sleep duration24. Among our results,
there was a positive association between frequency of presleep fantasizing and the GCTI questionnaire score,
which represents presleep thoughts insomniac subjects oen experience. We did not have information about the
contents of these fantasies, but previous studies showed that anxious and guilty characteristics of task-unrelated
thoughts might facilitate insomnia in opposition to positive-vivid topics25. e vast majority of participants were
women. Previous research has shown that ruminative coping strategies, as a response to stressful events, showed
gender dierences as early as in adolescence, with women generally more prone to developing depression26,27.
is may be a possible explanation for the association between the severity of insomnia and the frequency of
fantasizing: since our participants were mostly women, the nature of presleep thoughts may be ruminative.
In the second study, we analyzed almost 5000 presleep fantasy descriptions that were available online. Based
on the similar features of them, we isolated distinctive categories. e most common theme of these fantasies was
‘aims and ambitions’, which was about a broad range of underlying desires and reaching more or less reasonable
goals. is category contained fantasies that were generally more expressive in terms of storyline, mostly
pointing towards personal fulllment. ey may be an imaginative expansion of the current life situation, with
practical elements indicating problem solving and plans for the future. Previous research has shown that mental
imagery of a desired scene can be benecial if it contains real-life diculties to be solved, not only the achievable
award28. Romantic and sexual fantasies were reported commonly, which could benet the relationship29, and
were found to be acceptable, as a social norm, regardless of gender30. A lower subset of this category involved
aggressive thoughts, which could be associated with rumination and lower well-being31, revenge fantasies might
be even destructing32.
Based on our fantasy descriptions, the second most common category involved relaxing and peaceful scenes
where they can feel safe and unharmed. is sort of fantasy descriptions referred to self–soothing directly (e.g.,
“Since I was a kid, I have had a hard time falling asleep (…) I imagine I’m falling into my bed, like you’re on your
back in the pool and sink down to the bottom. But it is just darkness and I’m oating downward and I see the
bed and the hole I made above me growing distant. at is when I enter my dreams.”) or indirectly, suggesting
the contributing role to sleep quality.
In our sample, negative fantasies were illustrated less frequently, although smaller but not negligible fantasies
were classied under the sub-theme ‘fading away and death’. is category included fantasies, in which death
also illustrated peaceful content, and not necessarily just suicidal thoughts. is is supported by research ndings
that suicidal fantasies are associated with detailed suicidal dispositions rather than vague fantasies33.
Emotions associated with presleep thoughts might inuence the development of insomnia, although only
a few studies analyzed the quality of presleep cognitive activity. Most of the literature focuses on how anxiety,
rumination and worry at bedtime lead to cognitive hyperarousal and have a negative impact on sleep. us, these
ruminative thoughts are strongly associated with insomnia. Insomniac people tend to have worrisome thoughts
before sleep, they are oen concerned about their general mental state or even about the sleep process34. Presleep
thoughts of insomniac people revolve around topics like trivial thoughts, bodily sensations and concerns about
work, family and sleep35. Further discovery of these ndings, inuencing cognitive activity and transform
thoughts to positive emotions, could be an ecient way to prevent or relieve symptoms of insomnia2.
Internet use before bedtime in adolescents is associated with poorer sleep quality36. e causal relationship
between technology use and sleep problems has been shown in many studies, but the underlying mechanism
is still uncertain37. Internet use might interfere with presleep cognition, inuences the content of fantasies and
therefore disturbs the normal process of falling asleep, this could be a new way to approach sleep diculties.
ere are limitations of our studies that should be considered. Controversies of terminology makes it dicult
to compare ndings. In the literature we found several terms (such as mind wandering, daydreaming or fantasy)
to the occurrence of task-unrelated thoughts that are disengaged from the external stimuli. ey are oen
used as synonyms, and it is not clear if there is any dierence between them38. In the last decade, the word
“mind wandering” started to appear more frequently in scientic papers, slowly replacing “daydreaming” and
“fantasy”39. In this article we refer to the above-mentioned phenomena as a collective term, “fantasy”, as a more
conscious form of thoughts, as opposed to mind wandering which reects a more spontaneous dri of thoughts.
Future research should also focus on using a consistent terminology. In Study II, we collected presleep fantasy
descriptions and it was not part of the original question whether the fantasizing is common so it could be
possible that people’s fantasies alter depending on external factors such as a stressful day, which we unfortunately
could not assess. is would be avoidable with supplementary questionnaires. It is also complicated to separate
presleep fantasies, since they mostly overlap in topic, therefore it is dicult to choose the right category for
them. In this study, three individuals of our research team evaluated independently the content of the fantasies,
however, future studies would be able to strengthen the category system.
We hypothesized that positive thoughts may contribute to a better sleep quality, so a future direction could
be to instruct patients to actively fantasize about a particular content, which is strengthened by the result of no
association between the PSQI score and the frequency of presleep fantasizing. However, this assumption needs
to be conrmed by future studies, as other studies on fantasy analysis are scarce.
In conclusion, we found that cognitive activity before sleep in a form of fantasizing seems to be a common
phenomenon. As the results of Study II suggest, a categorization spreadsheet could be created based on the
similar fantasy patterns of dierent people, it would be practical to assess the relationship between dierent
categories and sleep quality. It may be important to distinguish between positivity-lled and negative fantasies
that may contribute to insomnia, as this aspect is rarely addressed in insomnia studies.
ScienticReports | (2024) 14:31975 7
| https://doi.org/10.1038/s41598-024-83642-7
www.nature.com/scientificreports/
Content courtesy of Springer Nature, terms of use apply. Rights reserved

Data availability
e data that support the ndings of this study are available from the corresponding author upon reasonable
request.
Received: 19 March 2024; Accepted: 16 December 2024
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Acknowledgements
None.
ScienticReports | (2024) 14:31975 8
| https://doi.org/10.1038/s41598-024-83642-7
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Content courtesy of Springer Nature, terms of use apply. Rights reserved

Author contributions
JJ, ASz, GD, RH and ASz were involved in developing the hypothesis and study design. ASz, GD and ÁA assem-
bled the questionnaire packages and summarized the results. ASz, EÁ and AHA evaluated the fantasy descrip-
tions and their categorization. ASz wrote the main manuscript body. JJ, NK, RH, ASz, BD and DG revised the
manuscript.
Declarations
Competing interests
e authors declare no competing interests.
Ethical approval
During this study, all methods were carried out in accordance with relevant guidelines and regulations. Based
on the ocial statement of the Regional Research Ethics Committee of the University of Pécs (9861 – PTE
2024) an Ethical Approval was not necessary for this study. Using this questionnaire was considered safe, as all
data were collected anonymously. With completing the online questionnaire, applicants voluntarily took part in
this study, and an informed consent was obtained from all participants. Regarding Study II, data was collected
from publicly available online platforms. For the protection of user privacy, our results did not contain any
identiable information about the users, and we have complied with the relevant terms and conditions of these
platforms. Due to the use of anonymized, publicly available data, and the position of Reddit, that collection of
data is not prohibited for academic purposes only (i.e. non-commercial), an ethical approval was not necessary,
supported by the statement of the Regional Research Ethics Committee of the University of Pécs (9861 – PTE
2024). Previous studies analyzing online data have followed a similar approach.
Additional information
Supplementary Information e online version contains supplementary material available at h t t p s : / / d o i . o r g / 1
0 . 1 0 3 8 / s 4 1 5 9 8 - 0 2 4 - 8 3 6 4 2 - 7 .
Correspondence and requests for materials should be addressed to G.D.
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