1. No category

IMAGINATION,
COGNITION
AND PERSONALITY,
Vol.28(1)37-48,2008-2009
DREAM CONTENT IN A REPRESENTATIVE
GERMAN SAMPLE: GENDER DIFFERENCES
AND THE EFFECTS OF OTHER
SOCIO-DEMOGRAPHIC VARIABL E S
MICHA E LS CHRE D L
KATHARINAKELLER
Central lnstituteof Mental Health,Mannheim,Germany
ABSTRACT
The presentstudy investigatedthe efl.ectsof socio-demographicvariableson
dream contentin a representativesample.The analysesof 380 most recent
variableslike age,
dreamsshowedthat almostnoneof the socio-demographic
gender,marital status,education,income,nor town (or city) of residencesize
was significantlyrelatedto generaldreamcharacteristics
like dream length,
bizarreness,and intensityof dream emotions,thus indicatingthat dreaming
is a universal phenomenonshared by all humans and is experiencedin
similar ways. On the other hand, dream content-in contrastto the general
dream characteristics is determinedby waking-life experiences.This is
clearly shown by the gender differences fbund in the present study: more
work-relatedthemesand physical aggressionin men's dreams.ln order to
generalizethesefindings,it will be necessaryto apply otherdreamcollection
methodslike dream diary or laboratoryawakeningsin large. representative
samplesin order to obtain and analyzethe dream reports of personswho do
not often recall their dreamsand who are not able to reooft their most recent
dreamto an interviewer.
37
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38 /
KELLER
SCHREDLAND
INTRODUCTION
The f,rrstcontentanalysisof a large sampleof dream reportswas publishedby
Hall and Van de Castle(1966).They included1,000diary dreamreports(length:
50 to 300 words) from 200 studentsaged l8 to 25 years, clicited in the timc
period from 1947 to 1950.In chapter14 of their book entitledNorms, Hall and
Van de Castle (1966) presentedthe coding resultsfor women and men separately.Many of thc findings,for example,regardingthe genderdifferences(more
physical aggression,more sexual activity, more outdoor settings,higher percentageof male drcam charactersin men's dreams) have been replicatedby
subseqnentstudies(e.g., Hall, Domhoff, Blick, & Weesner,1982. Schredl,
Sahin, & Schäfer, 1998) which were also most often carried out in student
samples.A preponderanceof male drearncharactersin tnen's dreamsand an
equal proportion of male and femalc charactersin women's dreams were
reported in many different samples (Hall, 1984). Findings based on nonstudent samplessometimesyielded difTerentresults; for example, Rubinstein
and Krippner ( 1991)found no genderdifferencein the percentageof male dream
charactcrsin dreamsof personswho answereda television announccmentfor
free dream intcrpretation.Similar, the rnale/femalepercentof dream characters
was corxparablefor men (58%) and women (51%) in thc study of Krippner et al.
(1998) who recruited participantsof drcarn seminars,mostly working adults.
However, the dream samplesof the non-studentsarnplesmight also be biascd,
for example,the dream selectedfor dream analysismight not be representative
for the dream life of this person. For investigating the effects of sociodemographicvariableslike age, gender,marital status,and cducationallevel.
dreamsamplesshouldbe studied.
representative
study of dreamcontenthas bccn reported
Up to now, only one representative
in the scientificliterature(Kramer, Winget, & Whitman, l97l; Winget, Kramer,
& Whitrnan, 1972).ln this study, 300 citizensof Cincinnati(a stratifiedrandorn
sample)were interviewedabout generalenvironmentalhealth issuesat home;
60.7% reporled a most recent dream in the course of the interview. Women
reporteddreamsmore often than men (65% vs. 53%). Mean dream length was
21 words. Most of the dreamreportswere describedas mundanewith a realistic
focus(Kramerct al., l97l). Using the Hall and Van de Castleratingscales,120%
of the dream reports included unpleasanternotionswhcreas only 40Ä includcd
positiveemotions.Applying anothercontentanalyticrating system(GottschalkGleser),the dreamreportswere divided into unpleasant(54o ), pleasant(26%).
and neutral (20%) dreams.The higher percentageof dreamswith ernotionsis
explainedby the differing codingrules sinceHall and Van de Castle( 1966)coded
only emotionsthat were explicitly mentionedwhereasthe Gottschalk-Glescr
systemsallows inferencesregardingemotionsfrom the drcatnaction.Work and
topicswcrc prescntin I 1.3%of the drearnreports(Kramer et al.,
business-related
1971\.Genderwas an importantfactor in cxplaininginterindividualdifferences,
DR E A MC ON TE N TS TU/ D39
Y
e.g.,men reportedmore dreamswith aggressionandwomenmore dreamemotions
(Winget et al., 1972).
The study, however,had severalmethodologicalproblems.First, the authors
did not report the percentageof participantswho did not consent to being
interviewed.Second.the time intervalsbetweeninterview and the occumenceof
the most recent dreams were not given in the published papers. Third, the
varistatisticalanalysisdid not investigatethe effectsof all socio-demographic
the
for
example,
might
be
biased,
the
findings
ables simultaneouslyand, thus,
explained
might
be
in
widower's
dreams
heightenedoccurrenceof deathanxiety
by age (cf. Winget et al., 1972).
ln the present study, the most recent dreams of a representativeGerman
samplewere analyzed.Regressionanalyseswere computedin order to test the
variablessimultaneously.
effect of all socio-demographic
ME T H OD
lnterview
The participantswere interviewedat home. ln order to elicit dream recall, a
7-point dreamrecall frequencyscale(codedfrom 0: never, I : lessthan once a
month. 2 : aboutonce a month, 3 : two or threetimes a month,4 : aboutonce a
week, 5 : Severaltimes a week, and 6 : almostevery morning) was presentedon
the monitor of a portablecomputer.The dreamrecall frequencyscalehas a high
retestreliability (r : .85; Schredl,2004a).Next, the participantswere askcd to
report their most recent drcam as completelyas possible(including characters.
actions,and emotions).The intervicwcr askedonce whetherthcre was anything
elsethey could remember.The dreamwas typed in by the interviewerwhile the
participantwas telling the dreamusing thc words of the dreamer.Lastly,the time
intervalbetweenthe dateof the dreamandthedateof the interviewwas recorded.
The following socio-dcmographicvariablcswere included in the study: age,
gender,education(five levels), income (15 levels ranging from "below 249
Euro per rnonth" to "over 5,000 Euro per month"), marital status(married/living
with partner,single/livingwithout parlner),and town (or city) of residencesizc
(7 levelsrangingfrom "below 2000 inhabitants"to "over 500,000inhabitants").
Dream Content Analysis
The dreamcontentanalyticscalesusedin this studywere adoptedfrom Schredl,
(l : realisticto 4 - two or more
Sahin,and Schäfer(1998):realism/bizarreness
bizane elementswithin the dream),positiveand negativeemotions(two 4-point
scales:0 : none, I : mild, 2 : moderate,3 : strong),numberofmale and female
dream characters,occurrenceof work-relateddreamsand occuffenceof verbal
and/or physical aggression.The interater reliability of these scalesare satisr : .642 (positive emotions),r : .825
factory, r : .765 (realism/bizarreness),
40 / SC HRE DLA ND
K E LLER
(negativeemotions),occurrenceof aggression(88% exact agreement;all data
from Schredl,Burchert,& Grabatin,2004). The exactagreementfor work-related
themeswas94.2oÄ(Schredl,1998).
Participants
Overall, a representativesample of 1,380 personswas drawn from German
householdsthat includepersonsover 14 yearsold. The samplesizewas reduced
to 1,033 (550 women, 483 men) becauseof dropouts due to the following
reasons:"not available for the interview" (1V: 180), refusing to participate
(N: 145),and other reasons(N :22). The responserate was 74.90Ä.The mean
age of the samplewas 47.9 years(^SD: 18.3).
Procedure
The study was carriedout by IpsosGmbH, Mölln, Germany.The participants
were contactedat home and interviewedconcerninga variety of topics (attitudes
toward chocolate,familiarity of specificproducts,amountof mediaconsumption,
etc.). The typed dreamreportswere edited in order to remove all information not
relatedto the dreamexperience(cf. Schredl,1999).Then the dreamreportswere
rated along the scalesdescribedin the dreamcontentanalysissection.Statistical
procedureswere carriedout with the SAS 9.1 softwarepackagefor Windows.
R E SU L T S
Overall, 36.8% of the participantsreporteda most recentdreamto the interviewer. The percentageof personsreportinga dreamdeclinedwith age whereas
variableshad no effect (see Table 1). Participants
the other socio-demographic
recall
reported
with high dream
a drcam more often than pcrsons with low
dream recall, the correlation between dream recall frequency and reporting
was s ign i fi c a n(r:
t
.4 8 J ,p < .0 0 0 1 ;y ' /: 933). The meanage
a dre a m(Ye s A r lo)
(214 women, 166rnen)reporlinga dreamwas46.4 years
of the 380 participants
(sD: 17.8).
For 322 dreamreports,thc participantsstatedwhcn thc dream occurred.The
answerswere classifiedinto threecategories57.8oÄof the dreamswere not older
than 14 days. 33.9% of the dreamswere drcamt between 14 days and one year
and only 8.4oÄof the dreamsoccurredrlorc than one year
before the interr'ziew,
prior to the interview. None of the socio-demographicvariables(age. gender,
maritalstatus,educationallevel, income,residencelocationsize)had an effect on
the time intervalbetweentelling the dreamandthe actualoccuffenceof the dream.
The mean length of the 380 dream reportsamountedro23.1 words (.SDl4).
Therewasno genderdifference(cf. Table2, women:23.5ISD I5.3] vs. men 22.5
variableswere also not associatedwith
ISD 14.2]).The other socio-demographic
dreamreportlength(seeTable 2).
D R E A MC ON TE N TS TUI D4.
Y
for DreamReportVariable(Yes/No)
Table1. LogisticRegression
(N : 1033)
Variable
Standardized
estimate
Stat.test
chi 2 :
P:
-.1035
7.5
.0062
.0541
2.3
.1327
0,4
.5146
Education
.0268
-.0298
0.6
.4333
Mo nt hlyinc om e
-.0337
0.7
.4168
.0468
1.7
.1970
Age
Ge n der
Maritalstatus
Placeof residentsize
scaleis depictedin Table 3. About
The distributionof the realism/bizaffeness
one-thirdof the dreamsincluded at leastone bizarre elementwhereasthe other
two-thirds of the dream reports were realistic but to some extent implausible
regarding the everyday world of the dreamer.Out of the socio-demographic
variables.only gender was associatedwith dream bizaneness,that is, women
reportedmore bizane dreamsthan men did (seeTable 2).
The intensitiesof positive and negative dream emotions are presentedin
Table 4. In 105 dreamreports(27.60Ä),the rater did not code any emotions.The
predominantlypositivedreams
dreamreportswere classifiedinto threecategories:
(28.2oÄ),and predominantlynegativedreams(42.1%\.
(29.7%),neutral/balanced
The difference in percentagebetween positive and negative dreamswas significant(Sign Rank test:S : 5056,p < .0001).None of the socio-demographic
variablescorrelatedwith positive or negativeemotionsexcept for the negative
associationbetween educationallevel and negative dream emotions. Participantswith higher educationallevelsreportednegativelytoned dreamslessoften
(se eT able2) .
Men reportedwork-relateddreamsmore often than women(19.3oÄvs. 10.3%).
This difference was statisticallysignificant (see Table 2) whereas the other
variablesdid not affect the amountof work-relateddreams.
socio-demographic
In men's dreams29 of the dreamcharacterswere male and24 were female.On
the other hand, 56 male dream charactersand 30 femaledream characterswere
found in women's dreams.The ratio of male charactersto the sum of male
and f'emalecharactersdiffered significantlybetweenthe sexes(men: 51.8% vs.
w o men:65. 1o/ o,ef f e c ts i z e d :0 .2 7 7 , z : -2 .6 ,p :. 0088). In a secondstep,the
analyseswas repeatedfor singlepersons(1/: 160; 60 men and 100 women) and
(N:220; 106men, 114 women).For men in
for personswith stablepartnerships
42 /
SCHREDLANDKELLER
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D R E A M C O N T E N T S T U D IY 4 3
Table 3. Dream Bizarreness (N = 380 Dream Reports)
Women
(N:214)
Category
Men
(N: 166)
Total
(N: 380)
Resembleordinaryeveryday
experiences
37.4"/"
50.o%
42s%
Dreamactionis possiblein waking
life but extraordinaryfor the
dreamer
3 6 .9 %
27.7%
32.9%
element
One bizarre(impossible)
withinthe dream
25.2"/"
223%
23.9"/o
0.0/"
0.37"
Two or more bizarreelements
withinthe dream
05%
Table4. Positiveand NegativeDream
Emotions(N : 380 DreamReports)
Category
Positive
emotions
Negative
emotions
No n e
69.7%
57j %
Mitd
1 4 .5 %
13.4%
Moderate
12.6%
21.6/"
3.2V"
7.9%
Strong
a paftncrshipthe rnale/femalepercentamountedto 47.2oÄ;for women living in a
partnershipit amountedto 63.4%. This differencewas significant (effect size:
-0.327,z: 2.4,p: .0153).For singlepcrsons,no significantdifferenccfor men
(60.0%) and women (66.7%) was found for the male/femalepercentof dream
characters.Interestingly,a significantdifferencein the ratio of male and female
dreamcharacterswas presentwhen women that were older than 40 (1/ - 49) were
comparedwith women youngerthan 40 (N : 5 I ). The ratio was balancedfor the
youngerwomen (47.1%)but not for the oldcr wornen(78.6%).The difference
( d: -0 .6 6 7 ,z : -3 .3 ,p : .0 0 0 9 ).
was s ignif ic ant
Forty percent of all aggrcssiveinteractionswere physical in men's dreams
whereas only 27.8oÄof the aggressiveinteractionsin women's dreamswere
44 / SCHREDLANDKELLER
physical.This differenceis statisticallysignificant(effectsize:d : 0.214 z : ) 5
p: .0124).
DISCUSSION
The findings of the presentstudy indicatethat the effect of socio-demographic
like dream length,dreambizarreness,
variableson generaldreamcharacteristics
and dream emotions is very small. On the other hand, gender differenceswere
found for specificdreamtopics(e.9.,morephysicalaggressionin men'sdreams).
In comparisonto the Kramer et al. (197l) study,the reportingrate was much
lower (36.8% vs.60.7oÄ).This might be explainedby the topicsof the interviews
which were relatedto health in the Kramer et al. study whereasin the present
study a wide rangeof topicsnot remotelyrelatedto sleepor dreamswas elicited.
Thus, by talking about dream-relatedissues in the Kramer et al. study, the
participantsmight have beenprimed, and the recall of most recentdreamsmight
have been facilitated.On the other hand, Kramer et al. ( 197l) did not reporl the
percentageof personswho refusedto participate.In the presentsample,25.IoÄof
the personsin the original random samplewere not intervieweddue to different
reasons(not availablefor the interview,refusing to participate).Similar figures
werc not reportedby Kramer et al. (1911).
As expected,reporting a dream was strongly correlatedwith dream recall
frequency.Similarto the Kramer et al. study,dreamreportingdecreascdwith age.
In order to include more dreamsof low dream recallers.other dreamcollection
methods with higher reporting rates would be necessary.Schredl (2002), for
example,reportedthat low dreamrecallersincreasedtheir ability to recall dreams
drasticallyby keepinga dreamdiary. Sirnilarly,Goodenoughet al. (1959)found
that 460Äof the REM awakeningsin the sleeplaboratoryyieldcd a drcam report
in personswith low dream recall at home. This figure is much lower than in
high dream recallers (93%) but it was a considerablcincreasecompared to
home dreamrecall which was about once a month. Using laboratorydreamsfor
sftrdyingrepresentativesamplesis difficult becausedream content is affected
by this measurementmethod. The overview of Schredl (2008) showcd that
19.4% of the laboratorydreamsincluded laboratoryelements(staff, electrodes,
etc.). This hgure increasedto 38.4oÄif indirect references(c.g., participatingin
an experiment)were also analyzed.Thus, laboratorydreamsdo not mirror the
ordinarydreamsof peoplein their everydaysetting.
Whether the interview settinghad an effect on the report rate or on the reported
drcam content (cf. Cartwright & Kaszniak, 1991) could not be determinedby
the presentdata. It would be interestingto carry out a represcntativestudy with
questionnairespostedto the participantsto investigatewhether the anonymity
of this settinghas an effect on reportrate and dreamcontent.
Over 90oÄof the dream reports occurredduring the last year, older dreams,
for examplc,childhooddreamswere extremelyrare.Kramer et al. (1971) did not
DR E A MC ON TE N TS TUI D45
Y
report the time intervalsbetweentelling the dreamand its occuffence.The higher
ratio of negativeto positive dreamsin the Kramer et al. study might be explained
variby including more childhood dreams.The investigatedsocio-demographic
ables were not associatedwith the time interval between dream reporting and
the occurrenceof dreams; thus, the findings regarding the effect of sociodemographicvariableson dream content were not affectedby this variable.
The meanlength of the dreamreportswas comparableto the findings of Kramer
et al. ( 197l). The interview dreamsare much shorterthan diary dreamsin young
adults (136 + lll.2 words; Schredl, 2004b) or elderly persons(41.2 + 43.4;
Schredl,Schroder,& Löw, 1996). Thus, the diary method might be useful to
obtain more elaboratedream material.On the other hand. dream bizarrenessis
comparableto diary dreams:about 25oÄof the presentdreamsincluded at least
one bizarre element(versus3l%; N : 365 diary dreams;Schredl, 1999; l9%;
N: 500 laboratorydreams;Strauch& Meier, 1996).The genderdifferencewas
small and not in accordancewith Schredl,Sahin, and Schäfer(1998) who did
not find a difference between the sexes.Thus, the presentfinding needs further
replication.
Regarding dream emotions, the representativesample of the most recent
of negativedreams.This might be
dreamsindicatethat there is a preponderance
explainedby recall bias becauseemotionalquality is balancedin diary dreams
(Schredl& Doll, l99B) and laboratorydreams(Strauch& Meier, 1996).It might
be that more negatively toned dreamsare more easily recalled-even after long
periodsof tirne (cf. Schredl,1999).
Marked genderdifferenceswere found for work-related drearns,ratio of male
and fernaledreamcharacters,and physicalaggression.The percentageof workrelated dreams in the present study (14.2%) were comparableto the figure
(11.3%) reportedby Kramer et al. (197l). Confirming the resultsof Schredland
Piel (2005), men reportedwork-relateddrearnsmore often than women. This is
in line with the continuityhypothesisof dreaming(cf-.Schredl,2003)becausethe
employmentrate is higherin men comparedto women (64.9% [men] vs.45.60Ä
Bundesamt,
fwornen]:personsolder than 20 years;Mikrozensus,Statistisches
Bonn,Gennany;cf-.Schredl& Piel, 2005).
hr the total sample, women's dream showed a higher percentageof male
dream charactersthan rnen's dreams; a finding never reported before (cf.
Domhoff, 1996;Hall. 1984;Hall & Dornhoff,1963).However,if the percentages
of male and t-emaledream charactersfor the dreams of young singles and
the figures
were computedseparately,
the dreamsof personswith relationships
resernblethe findingsof Schredl(2001).This authorreportedthe "ubiquitous"
gender differences for singles (preponderanceof male dream charactersin
men's dreams and a balanced ratio of the dream characters'gender in
women'sdreams)but a differentsituationfor personswith stablepartnerships:
62.3'%rnaledreamcharacters
werc fbund in women's dreamsand in 48.7nÄin
men'sdrearns.
4 6 / SC HRE DLA NDK E L L E R
The major difference betweenthe presentstudy and the results of the student
sample(Schredl,Sahin,and Schäfer,1998)is the high percentageof male dream
charactersin dreamsof women older than 40 yearsof age.Basedon the findings
that the amount of time spent with the different sexesin waking life is colrelated with the male/femalepercentof dreamcharacters(Schredl& Jacob,1998;
Schredl,LoBnitzer,& Vetter, 1998),one might speculatethat singlewomen over
40 spenda lot of time with males(friends,colleagues).Another line of thinking
might draw on the findings of Strauch and Meier ( 1996) that waking thoughts
affect dream contentas well and some older women who were widowed might
have strong memories of their former husbands and, thus, dream more often
about men.
The present study confirmed findings in student samples reported earlier
(Domhoff, 1996;Hall & Van de Castle,1966;Schredl,Sahin,& Schäfer,1998)
that men dream more often about physical aggression than women. This
might reflect a higher pronenessto violence in men (cf. Schredl, Sahin, &
Schäfer,1998).
Overall, the findings that almost none of the socio-demographicvariables
like age, gender,marital status,education,income, and residencelocation size
was significantly related to general dream characteristicslike dream length,
and intensityof dreamemotionsindicatethat dreaming,asa universal
bizarreness,
phenomenonshared by all humans, is experiencedin similar ways. On the
other hand, dream content-in contrastto the general dream characteristics-is
determinedby waking-life experiences,this being clearly shown by the gender
differences found in the present study. In order to generalizethese findings, it
will be necessaryto apply other dream collection methodslike dream diary or
laboratory awakenings in large, representativesamples in order to obtain and
analyzedream reports of personswho do not often recall their dreamsand who
are not able to report a most recent dream to an interviewer.
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