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Research report

Creativity and affective temperaments in non-clinical professional artists: Anempirical psychometric investigation

Marcello Vellante a, Giulia Zucca a, Antonio Preti a,b,⁎, Davide Sisti c, Marco Bruno Luigi Rocchi c,Kareen K. Akiskal d, Hagop S. Akiskal d,e

a Department of Psychology, University of Cagliari, via Is Mirrionis 1, 09123 Cagliari, Italyb Genneruxi Medical Center, via Costantinopoli 42, 09129 Cagliari, Italyc Institute of Biomathematics. Polo Scientifico, Loc. Crocicchia, University of Urbino, 61029 Urbino PU, Italyd International Mood Center, La Jolla, CA, USAe University of California at San Diego, La Jolla, CA, USA

a r t i c l e i n f o a b s t r a c t

Article history:Received 27 March 2011Received in revised form 29 June 2011Accepted 30 June 2011Available online 5 August 2011

Objective: Manic-depression/bipolar disorder was linked to creativity, with affectivetemperaments allegedly favoring creative expression and achievement, but a few studiesonly empirically tested the link.Methods: 152 undergraduate students attending preparatory courses for creative artisticprofessions and 152 students in areas expected to lead to a profession mostly requiring theapplication of the learned rules were invited to fill in the TEMPS-A (Temperament Evaluationof the Memphis, Pisa, Paris and San Diego — Autoquestionnaire), the General HealthQuestionnaire (GHQ) and the Creative Achievement Questionnaire (CAQ). Latent classanalysis (LCA) was used to investigate the links between creativity scores and measures ofpsychopathology.Results: Creative participants and controls did not differ in terms of sex (males=47%), age(24.5 years, SD=3.8), or socioeconomic status. Creative people scored higher than controlson the CAQ and on the cyclothymic, hyperthymic and irritable subscales of the TEMPS-A, butnot on the GHQ. Greater involvement in creative activities rather than being a creativeachiever best differentiated those into the “risk for bipolar spectrum” class from the othertwo classes extracted by the LCA from the TEMPS-A.Limitations: The use of self-report measures to evaluate both creative involvement and the risk ofpsychopathology, and the exclusive focus on artistic creativity limit the generalizability of thefindings.Conclusions: This study confirms that the cyclothymic dimension of the bipolar spectrum is linkedto creativity, and this link is likely to result from increased involvement into pleasurable activities,including creative ones.

© 2011 Elsevier B.V. All rights reserved.

Keywords:Mood disordersBipolar spectrumTemperamentCreativityPersonality

1. Introduction

Akiskal's bipolar spectrum (1977; 1981; 1983) conceptu-alizes mood disorders alongside the Kraepelinian notion of a

broad manic-depression syndrome extending from subclinicalmanifestations to bipolar I disorder, and encompassing majorand minor depression, cyclothymic disorder and the variant ofbipolar disorder with hypomania (bipolar II). The TEMPS-A(Temperament Evaluation of the Memphis, Pisa, Paris and SanDiego — Autoquestionnaire) was developed to more preciselydefine the temperamental foundation of bipolar spectrum,withfive subscales (dysthymic, cyclothymic, hyperthymic, irritable,

Journal of Affective Disorders 135 (2011) 28–36

⁎ Corresponding author at: Centro Medico Genneruxi, Via Costantinopoli42, 09129 Cagliari, Italy. Tel.: +39 070 480922.

E-mail address: apreti@tin.it (A. Preti).

0165-0327/$ – see front matter © 2011 Elsevier B.V. All rights reserved.doi:10.1016/j.jad.2011.06.062

Contents lists available at ScienceDirect

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andanxious) aimedatoffering amultidimensional evaluationofthe affective temperaments that characterize people within thebipolar spectrum (Akiskal and Akiskal, 2005a). The TEMPS-A isrooted in an evolutionary biologic perspective (Akiskal andAkiskal, 2005b), which has received some support from geneticstudies (Gonda et al., 2005; 2009).

Both past and recent studies purported a link betweenmanic-depression/bipolar disorder and creativity (Murray andJohnson, 2010; Srivastava and Ketter, 2010), with emphasis onthe cyclothymic component of the manic-depression/bipolardisorder spectrum (Akiskal and Akiskal, 1988; Andreasen,1987; Juda, 1949; Kretschmer, 1931; Ludwig, 1992; Richards etal., 1988; Srivastava et al., 2010; Strong et al., 2007).

Positive mood, and happiness in particular, was postulatedto fuel creativity (Baas et al., 2008; Davis, 2009). Enhancedpositive affect is a feature of both hypomania andmania, whichare core symptoms of bipolar disorder and may predisposepeoplewithin themanic-depression/bipolar disorder spectrumto creativity (Murray and Johnson, 2010). By contrast, Akiskaland Akiskal (1988) postulated that depression might providefresh insights which can be executed into the artistic oeuvreduring the energized phases of cyclothymia.

Whether or not creativity is linked to bipolar disorder has animpact on clinical practice. Lithium was reported to negativelyinfluence verbal learningandmemory andnegatively impact oncreativity (Wingo et al., 2009); however, Schou's (1979)classical study on artists did not support this point of view. Nospecific evidence is available onother drugsused to treatbipolardisorder. Overall the area is understudied (Andreasen, 2008;Murray and Johnson, 2010). Albeit these cognitive effects werereported to be small, therapists treating patients with bipolardisorder should be aware of the impact of pharmacotherapy onpatients involved in artistic, scientific or otherwise creativeprofessions, and be especially careful with young patients whohave not defined a profession yet. Indeed, better prophylaxis ofthe disruptive episodes of manic-depression can have overallbeneficial effects on the career of artists (Akiskal and Akiskal,1988).

Most studies originating evidence on a link betweenbipolar disorder and creativity were based on small, highlyselected samples, or considered retrospective accounts onpsychopathology (Akiskal and Akiskal, 1988; Andreasen andGlick, 1988; Jamison, 1989; Jamison, 1993; Nowakowska etal., 2005).

Only one study with reliable epidemiological data found anoverrepresentation of people diagnosed with bipolar disorderamong those who declared an “artistic” profession; the studywas based on the Epidemiological Catchment Area Study, andincluded 20,861 adult participants (Tremblay et al., 2010).However, peoplewith bipolar disorder often have difficulties infinding and maintaining a job, so greater representation inartistic professions might be the effect of social drift in lessstructured anddemandingoccupations rather than the result ofa personal talent in creativity. Indeed, people with bipolardisorder as those with a cyclothymic temperament may fitbetterwith less structured activities and environments as thosetypical of creative professions, in which they do not have to besubordinates or follow strict rules.

Nevertheless, some features of bipolarity might contributeto creative expression and success. Indeed, creativity issomething more than merely being able to connect remote

associations between known ideas and concepts to produceoriginal or otherwise new constructs or tools. The capacity ofbringing new or original creations to social testing, bycomparison with scientific or aesthetic standards, and winningagainst criticism is a crucial factor in creative achievement(Preti and Miotto, 1997).

Anecdotal evidence indicates that creative people tend toemerge as both sociable and popular with their peers; they alsoappear to welcome social contact and show interest in socialactivities (Post, 1994).When specifically investigated, increasedextraversionwas found in a sample of creativepeople comparedto less creative peers or people involved in noncreativeprofessions (Feist, 1998; Gelade, 1997), although negativefindings have been reported as well (Feist, 1998). Elevatedextraversion has also been observed in patients with bipolardisorder (Akiskal et al., 2006; Murray et al., 2007). Increasedsociability is a feature of hypomanic states (WHO, 1992), andcan be observed in patients diagnosed with bipolar disorderwhen they are not overtly disturbed by the depressive ormanicphasesof their psychopathology. Sociability is a core componentin creative achievement, and the ability to promote oneself bynetworking might be a factor linking creativity and affectivedisorders (Sass, 2001).

Openness to experience and intuitive thinking are twocentral features of creativity, and both patients diagnosed withbipolar disorder and people involved in creative professionswere reported to score higher in openness (asmeasured by theNeuroticism, Extraversion, andOpennessPersonality Inventory:Costa andMcCrae, 1985) and intuitive thinking (asmeasuredbythe Myers–Briggs Type Indicator, which is based on Jungiantypes: Myers and McCaulley, 1985) than comparison groups(Srivastava and Ketter, 2010).

Finally, a strong ambition and drive to success characterizepeople who excel because of their creative talent (Feist, 1998),and ambition for success and recognition by others are featuresobserved in people diagnosedwith bipolar disorder or at risk ofit (Johnson et al., 2009; Murray and Johnson, 2010).

A few studies tested the hypothesis that bipolar disorderwould promote creativity by recruiting patients with bipolardisorders, and assessing their creative potential and talentwith instruments aimed at measuring propensity to becreative. Akiskal and Akiskal (1988) reported that artistictalent, creativity, and eminence in various professionaldomains were over-represented among the kind of affectivedisorders versus schizophrenia patients. In one of the twoother studies published on this topic to date, the closerelatives of patients with bipolar disorders were found morecreative than healthy people not at risk of affective disorderson a scale designed to test everyday creativity (Richards et al.,1988); in another study (Santosa et al., 2007), patients withbipolar disorder in euthymic phase scored higher thancontrols devoid of affective disorders on the Barron–WelshArt Scale (Barron, 1963) but not on the Torrance Tests ofCreative Thinking (Torrance, 1990).

Another large study based on an affective disorder samplefound increased cyclothymia in artists and architects comparedwith people involved in noncreative professions (Akiskal et al.,2005a). One study done in a non-clinical sample and involving128 students found an association between hypomanicpersonality traits and the scores on three measures of creativepotential (Furnham et al., 2008). A link between a measure of

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creative production and a past or current history of treatmentformooddisorderwas found in yet another non-clinical sampleincluding 412 undergraduate students (Guastello et al., 2004).One of the problems of research in this area is that comparisongroups need to be broad enough to provide perspective on thehypomanic and energized aspects of temperament among theartist types. In a study (Figueira et al., 2010) among medicalstudents, their temperamentswere unremarkable, law studentsand art students were cyclothymic and irritable; engineeringstudentswere predominantly hyperthymic,while psychologistsand nurses were predominantly depressive or anxious intemperament. This contrast provides some relative specificityfor cyclothymia and creativity.

The limited evidence frompast studies suggests that creativeachievement would relate to milder forms of hypomania, whilemore severe expressions of symptomsmaynegatively influencecreative accomplishment (Akiskal and Akiskal, 2007; Richardset al., 1988; Simeonova et al., 2005). Therefore, the investigationof the affective temperament in non-clinical populations couldoffer more specific clues on the links between creativity andbipolar disorder and the mechanisms involved in it.

In this study we tested whether students in creativedisciplines were more likely than students in non-creativedisciplines to show indicators of affective temperament.

To this aim, we used the TEMPS-A. To date, the original110-item version has been translated into 25 languages, andvalidated in many countries with different cultural back-grounds (Akiskal and Akiskal, 2005a).

This study used the Italian brief, 39-item version of thequestionnaire, which proved as valid as the longer version, andit is somehowmore apt at investigating large samples from thecommunity (Preti et al., 2010).

Distribution of scores on the TEMPS-A subscales wasexplored with Latent Class Analysis (LCA). LCA posits that aheterogeneous group can be reduced to several homogeneoussubgroups by evaluating and then minimizing the associationsamong responses across multiple variables, and tests for theexistence of discrete groups with a similar symptom or itemendorsementprofile (LazarsfeldandHenry, 1968;McCutcheon,1987). On a theoretical basis, we expected that TEMPS-A scoresbe distributed into three classes: a large basal class with thelowest chance of endorsement of TEMPS-A items (peopledevoid of affective traits); a depression-prone class,withhigherendorsement within the dysthymic and anxious tempera-ments; and a cyclothymic-prone class, including those peoplewho are likely to endorse most TEMPS-A items within alltemperaments. To the best of our knowledge, this is the firststudy applying LCA to the TEMPS-A.

2. Methods

2.1. Participants

The study was approved by the ethical board on clinicalinvestigation of the Department of Psychology of theUniversity of Cagliari. A total of 350 participants were invitedto fill in a booklet containing some self-report questionnairesaimed at investigating creativity and their psychologicalcorrelates, including indicators of psychopathology.

Three hundred and four participants completed the ques-tionnaires: 152 were attending schools preparing for creative

artistic professions in the district of Cagliari (44 musicians intraining at the conservatoire, 36 painters and sculptors intraining in fine arts, 40 dancers, and 32 actors from dramaschool), and152 subjectswere attendingundergraduate coursesof the University of Cagliari in areas expected to lead to aprofession mostly requiring the application of the learned rules(59 from the engineering courses, 60 from the law courses, and33 from the foreign language courses).

Criteria for inclusion in the index group (hereinafter“creative people”) were: to be undergoing studies leading toan artistic profession requiring the production of brand new,originalworks; to be expected to be exposed topublic judgmentof the produced works, via an exhibition (for painters/visualartists), public execution of musical compositions (for musi-cians), expression/playing in public (for dancers/dramatists),during their course.

Criteria for inclusion in the contrast group (hereinafter“controls”) were: to be undergoing studies leading to aprofession requiring the application of rules, without specifi-cally being requested to innovate their field; to be expected notto be exposed to public judgment of any creatively producedwork, in any field, during their course.

We tried to match undergraduate courses to the artisticschools, as far as the cognitive abilities required to be successfulin the field were concerned (playing/persuasion for both lawstudents and dramatists/dancers; abstraction and symboliza-tion for engineers and musicians; visual artists and students oflanguages were unmatched).

The group of creative people was specifically matched forsex to the group of controls, since self-report measures ofpsychopathology tend tobehigher in females than inmales anddifferences by sex between the samples would have biasedresults.

The study was carried out from spring 2008 to spring2010. Each participant provided informed consent. Voluntaryparticipation (no fee paid) and having no impediment inreading and understanding the Italian language correctlywere the only criterion of inclusion. The participation ratewas 83.5% in the creative group and 90% in the control group(Fig. 1).

2.2. Measures

Each participant was guaranteed confidentiality of theinvestigation, and subsequently received a booklet containingthe questionnaires listed below, which they were asked tocomplete.

The Creative Achievement Questionnaire (CAQ): this is aself-report measure of creative involvement and achievementthat includes 10 domains of creativity, from the arts andscience to humor and culinary (Carson et al., 2005). Threesubscales apply here: one on self-evaluation assessing thenumber of creative areas inwhich the participant is involved; asecond scale records major achievements by the participant inany creative domain, and consists of a summary score on 10areas rated 0 (no talent whatsoever) to 7 (public acknowl-edgement of the subject's talent on a national journal); a thirdscale (3 items, yes/no format=1/0) depicts how the partici-pant is viewed by others as a creative stereotype (e.g. “Peopleregularly accuse me of having an ‘artistic’ temperament”). Theoriginal version showed good convergent and predictive

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validity as far as other measures of creativity were concerned.For the purpose of this study, the original English version of theCAQ was translated into Italian by the principal investigator(AP) then checked for correctness by an English-speakingtranslator. A second English-speaking translator checked theback translation into English.

The 12-item General Health Questionnaire (GHQ-12): thisscale is a 12-item self-report questionnaire on which respon-dents rate the degree of their psychological distress – accordingto the major symptoms area of mental disorders – on a 4-pointscale (“not at all”, “less than usual”, “more than usual”, “rathermore than usual”), with reference to the past 4 weeks(Goldberg, 1972; Politi et al., 1994). The respondents whomarked any statement in the scale applying to them “rathermore than usual” or “more than usual” scored 1, whereas thosereporting “less than usual” or “not at all” scored 0 (maximum

score=12); this scoring method proved reliable enough todiscriminate people suffering from a mental disorder fromputatively healthy subjects (Politi et al., 1994). The aggregatescores equal to 4 or higher (out of 12) typically classify cases ofcommon mental disorder, including adjustment disorders orstress reactions.

The brief Temperament Evaluation of the Memphis, Pisa,Paris and San Diego — Autoquestionnaire (TEMPS-A): this is a39-item yes-or-no self-report questionnaire designed toquantify affective temperaments in psychiatric patientsand healthy subjects. It derives from a longer, 110-itemversion, built-up on the concept of bipolar spectrum, andincludes five subscales: dysthymic (D), cyclothymic (C),hyperthymic (H), irritable (I) and anxious (A) (Akiskal andAkiskal, 2005a). The validated Italian version, prepared viatranslation and back-translation of the original brief scale,

Population PopulationUniversity students: n = 9437 Arts schools students: n = 1900

Engineering : 5726 Fine arts: 300Law: 2836 Dancing: 500 Language: 875 Drama: 300

Conservatoire: 800

Assessed for eligibility (n = 182)

Fine arts: 46Dancing: 40Drama: 40Conservatoire:56

Assessed for eligibility (n = 168)

Engineering: 63Law: 67Language: 38

Enrollment

Excluded (n = 30)

Not meeting inclusion criteria(n = 0)

Refused to participate(n = 0)

Other reasons (not returned booklet) (n = 28)(incomplete data) (n = 2)

Excluded (n = 16)

Not meeting inclusion criteria(n = 0)

Refused to participate(n = 0)

Other reasons (not returned booklet) (n = 16) (incomplete data) (n = 0)

Analysis

Analyzed (n = 152)

Excluded from analysis (n = 0)

Analyzed (n = 152)

Excluded from analysis (n = 0)

Fig. 1. Flowchart of the study — STROBE diagram.

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was used for this study (Preti et al., 2010). The TEMPS-Aproved able to readily distinguish patients with bipolardisorder from healthy subjects, and it considered a gooddescription of the affective temperaments in both clinicaland non-clinical samples (Akiskal et al., 2005b).

2.3. Statistical analysis

All data were coded and analyzed using the StatisticalPackage for Social Sciences (SPSS) for Windows (Chicago,Illinois 60606, USA), version 13.

Scale reliability was measured by Guttman's lambda2(Guttman, 1945), which is now considered a better lowerbound estimate of reliability than Cronbach's alpha (Sijtsma,2009). To compare groups, reliability values of .70 areconsidered satisfactory (Bland and Altman, 1997). However,when dealing with subscales derived from a single question-naire, values around .60 are considered acceptable (Nunnally,1978).

All tests were two-tailed, with a conservative p=.05. Alldata were analyzed with non-parametric statistics due tonon-normality (Kolmogorov–Smirnov, with Lilliefors signif-icance correction, pb .01 or lower in all explorations).Categorical data were analyzed in between-group compari-sons with χ2, with Yates correction when appropriate. TheMann–Whitney test was used to compare the ordinal vari-ables. Spearman's rho correlation coefficients were used toexamine associations between two continuous variables.

LCA was conducted with Mplus 3 (Muthén and Muthén,2004). The Lo–Mendell–Rubin's adjusted likelihood ratio test(LRT: Lo et al., 2001) was used to compare models withdifferent numbers of latent classes. Model selection wasconducted according to fitting indices (lower values=betterfit) such as likelihood ratio (−2*Ln(L)), the Akaike informa-tion criterion (AIC: Akaike, 1987), the Bayesian informationcriterion (BIC: Schwarz, 1978), and the sample-size adjustedBIC (SSABIC: Sclove, 1987). Standardized entropy measurewas used to assess accuracy in participants' classification(values range 0 to 1), with higher values indicating betterclassification.

Multinomial logistic regression was used to assess theassociation between class membership and creativity (scoreson the CAQ) variables, taking into account demographic (i.e.gender and age) and clinical (scores on the GHQ-12) variables.

Differences between classeswere expressedwith odds ratiowith 95% confidence interval (CI), except for scores on theTEMPS-A subscales. The extraction of the LCA classes was notindependent from the scores on the TEMPS-A subscales, so noinferential statistics could be calculated. However, for descrip-tive purposes, mean and standard deviations of TEMPS-Asubscales by classes were reported, and the effect sizes ofdifferences between classes were calculated according to Cliff'sdelta (with C.I.), which is appropriate in case of violations ofnormality. The Cliff's delta represents the degree of overlapbetween the two distributions of scores: the greater theoverlap, the less the difference between the groups (Cliff,1993). It ranges from −1 to +1 (according to the order ofoverlap between two groups), and takes the expected value ofzero if the two sample distributions are extracted from thesame population.

2.4. Sample size

We carried out a preliminary power calculation to deter-mine theminimumsample size to test our hypothesis. Basedont-test,wedetermined that a sample of 52participants per groupwould be needed to achieve 80% power to detect a differencewithd=0.50 (mediumeffect size) in themeasures of creativityand in those of psychopathology, at a 2-sided significance levelof .05 and allocation ratio of 1 to 1. For its corresponding non-parametric test (Mann–Whitney test), a sample of 64 partic-ipants per group would be needed at the same levels of powerand significance (the efficiency of the Mann–Whitney test isabout 0.95 of its corresponding t-test) (Lehmann, 1975).

Calculation was done with G*Power 3 (Faul et al., 2007).

3. Results

Creative people and controls did not differ in terms of sex,age, socioeconomic status (as measured by the educationallevel of their parents) and marital status (Table 1).

The reliability of most questionnaires in the sample wasacceptable (Guttman's lambda2 higher than .70 or near it insubscales), with the possible exception of the hyperthymicsubscale of the TEMPS-A (Guttman's lambda2=.58).

On the CAQ, creative participants described themselves asmore involved in creative activities than controls; they alsoreported greater achievements in the explored fields, and tobe more likely to correspond to the “creative” stereotype inthe eyes of friends and acquaintances (Table 2).

Creative participants did not score higher than thecontrols on the GHQ-12, but they differed from the controlson the cyclothymic, hyperthymic and irritable subscales ofthe TEMPS-A.

The CAQ involvement, achievements and stereotype sub-scales were positively related to the cyclothymic and thehyperthymic subscales of the TEMPS-A (Table 3).

Table 1General characteristics of the sample (n=304).

Sociodemographicgroup

Creative people(N=152) N (%)

Controls(N=152) N (%)

Statistics

Gender χ2[1]=0.00,p=1.00

Male 71 (46.7%) 71 (46.7%)Female 81 (53.3%) 81 (53.3%)

AgeMean (SD) 24.2 (4.4) 24.9 (3.3) t(302)

=1.53,p=.12

Highest level ofparental educationLower than highschool diploma

44 (28.9%) 52 (34.2%) χ2[2]=2.05,

p=.36High schooldiploma

66 (43.4%) 68 (44.7%)

College graduateor higher

42 (27.6%) 32 (21.1%)

Marital statusUnmarried 149 (98.0%) 146 (96.1%) χ2

[1]=0.45,p=.49

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As expected, the GHQ-12 was positively related to allsubscalesof theTEMPS-A,with theexceptionof thehyperthymicsubscale. No significant links emerged between GHQ and CAQscores.

3.1. Latent class analysis

The 3-class solution was the best compromise between allthe considered indexes. The AIC and the SSABIC progressivelydeclined across the differentmodel, until a plateau at the 4classsolution (12010.8 and 12097.6, respectively, versus 12109.2and 12174.1 in the 3-class solution); the BIC decline was moreclear-cut, and values in the 4-class (12601.8) and the 5-classsolution (12741.6) were higher than in the 3-class solution(12551.5). In the 3-class solution the entropy was .88, whichindicated a good classification of participants in the model.

This solution yields to a baseline class (LC1) with lowendorsement of most TEMPS-A items, including 103 partici-pants (33.8%), and two classeswith scores into the symptomaticinterval on both the cyclothymic and thedysthymic subscales of

the TEMPS-A: the LC2 includes 136 (44.7%) participants, whilethe LC3 includes 65 (21.3%) participants.

Compared to the baseline class (LC1), the LC2 class hadhigher scores on the dysthymic, cyclothymic, irritable, andanxious TEMPS-A subscales, but not on the hyperthymicsubscale. The LC3 class had higher scores than the baselineclass on all TEMPS-A subscales. LC3 class also had higher scoresthan the LC2 class on thedysthymic (Cliff's delta=0.58; 95% CI:0.39 to0.72) and cyclothymic (0.93; 0.84 to0.97) subscales, andalso, but at lower effect size, on the hyperthymic (0.34; 0.12 to0.53), irritable (0.22; 0.03 to 0.39), and anxious (0.22; 0.01 to0.41) subscales.

Overall, the LC3 class had the highest probability ofendorsement on all items, while the LC2 endorsement wasintermediate between the baseline class and the high endorse-ment class (Fig. 2).

There were no differences by gender. Younger people andpeople scoring above the threshold for clinical case on theGHQ-12weremore likely inboth symptomatic classes (LC2andLC3) compared to the baseline class (LC1). CAQ involvementbut not CAQ achievement or the CAQ “creative” stereotypescores associated with LC3 (Table 4).

4. Discussion

This study found students involved in courses leading to acreative profession scoring higher than an age- and gender-matched control group on the TEMPS-A (a measure of affectivetemperaments). TEMPS-A more than GHQ-12 (a measure ofcurrent psychological distress used to screen clinically activemental disorders) differentiated creative participants fromcontrols. As suggested by past literature, the cyclothymicsubscaleof theTEMPS-Awas specifically related toabiographicalmeasure of creative achievement, the CAQ. As in past studies,therewasa relativelyhighendorsement rate on thehyperthymicand anxious TEMPS-A items, since these items cover sociallydesirable traits in the Italian population (Placidi et al., 1998;Akiskal et al., 1998; Preti et al., 2010).

This study also provided the first evidence that scores onthe TEMPS-A can be decomposed into clusters with adifferent level of endorsement on the dimensions that definethe bipolar spectrum, with a class endorsing on thedysthymic, cyclothymic, and hyperthymic subscales defininga putatively “risk for bipolar disorder spectrum” class. Indeed,

Table 2Differences by measures of creativity and psychopathology between creativepeople and controls.

Creative people(n=152)

Controls(n=152)

Mann–WhitneyU test

Mean (SD)median

Mean (SD)median

CAQinvolvement

3.4 (1.8) 3.0 2.4 (1.8) 2.0 U=7959.0, pb .0001

CAQachievements

7.5 (4.7) 7.0 2.8 (2.7) 2.0 U=3800.5, pb .0001

CAQ stereotype 1.0 (0.7) 1.0 0.4 (0.5) 0.0 U=5966.0, pb .0001GHQ-12 3.6 (3.3) 3.0 3.4 (3.1) 3.0 U=11229.0, p=.671TEMPS-A

Dysthymic 1.6 (1.6) 1.0 1.9 (2.0) 1.0 U=11074.5, p=.523Cyclothymic 5.0 (3.1) 5.0 3.8 (2.9) 4.0 U=9121.0, p=.001Hyperthymic 3.1 (1.9) 3.0 2.6 (1.7) 2.0 U=9740.0, p=.017Irritable 1.5 (1.6) 1.0 1.1 (1.4) 1.0 U=9875.5, p=.028Anxious 1.2 (1.1) 1.0 1.2 (1.0) 1.0 U=11533.0, p=.979

CAQ = The Creative Achievement Questionnaire.GHQ-12 = The 12-item General Health Questionnaire.TEMPS-A = The Temperament Evaluation of the Memphis, Pisa, Paris andSan Diego — Autoquestionnaire.

Table 3Matrix of correlations between measures — total sample (n=304).

CAQ TEMPS-A

Involvement Achievement Stereotype Dysthymic Cyclothymic Hyperthymic Irritable Anxious

TEMPS-ADysthymic .029 − .029 .051Cyclothymic .251⁎⁎ .207⁎⁎ .179⁎ .515⁎⁎

Hyperthymic .313⁎⁎ .272⁎⁎ .253⁎⁎ − .076 .229⁎⁎

Irritable .161⁎ .116 .128 .307⁎⁎ .455⁎⁎ .256⁎⁎

Anxious .044 − .058 .071 .276⁎⁎ .331⁎⁎ .080 .207⁎⁎

GHQ-12 .141 .090 .076 .323⁎⁎ .406⁎⁎ .016 .211⁎⁎ .152⁎

CAQ=The Creative Achievement Questionnaire.GHQ-12=The 12-item General Health Questionnaire.TEMPS-A=The Temperament Evaluation of the Memphis, Pisa, Paris and San Diego — Autoquestionnaire.⁎ Spearman's rho pb .01.⁎⁎ Spearman's rho pb .0001.

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the LC3 includes people with positive endorsement on mostTEMPS-A items, and scores on this class were close to thoseobserved in past studies with TEMPS-A applied in clinicalsamples (Akiskal et al., 2005a,b, 2006). However, since thestudy did not include a clinical group, we cannot betterestablish the exact correspondence of this class to the bipolarspectrum, nor can we ascertain the clinical nature of theintermediate LC2 class, whether it is still within the bipolarspectrum, albeit in an attenuated form, or defines a profile

indicative of a predisposition to mood and anxiety disordersoutside the bipolar spectrum.

Scores on the GHQ-12 were statistically higher in the LC2and the LC3 than the baseline LC1 class, providing validity tothe retrieved solution.

Sample size precluded the further differentiation of a “riskfor bipolar disorder spectrum” class into a “predominantlymajor depression class” and a “truly bipolar disorder class”. Afour-class solutionwas discarded because it did not fit well on

Fig. 2. Profile plot for the latent class analysis of the TEMPS-A (39 items). The Y-axis represents the class-specific mean scores as proportions of themaximum scorefor the indicator concerned. The X-axis contains the 39-item profile of the TEMPS-A.

Table 4Distribution of TEMPS-A and measures of creativity and psychopathology in the 3-class solution.

All data: n (%)or mean (SD)

LC1 LC2 LC3

n=103 n=136 n=65

SexMales, n (%) 59 (57%) 56 (41%) 27 (41%)Females, n (%) 44 (43%) 80 (59%) 38 (59%)

1 OR=0.57 (0.32–1.00) OR=0.60 (0.29–1.23)Age 25.5 (3.8) 24.4 (3.9) 23.3 (3.6)

1 OR=0.91 (0.85–0.98) OR=0.83 (0.76–0.92)GHQ-12 1.9 (2.5) 4.1 (3.2) 5.0 (3.1)

1 OR=1.33 (1.19–1.48) OR=1.45 (1.27–1.64)CAQ

Involvements 2.5 (2.0) 2.8 (1.7) 3.7 (2.0)1 OR=1.06 (0.92–1.33) OR=1.37 (1.10–1.71)

Achievements 5.0 (5.2) 4.7 (3.8) 6.4 (4.8)1 OR=0.94 (0.87–1.02) OR=0.99 (0.90–1.08)

Stereotype 0.6 (0.7) 0.7 (0.7) 0.8 (0.6)1 OR=1.33 (0.84–2.09) OR=1.17 (0.67–2.05)

TEMPS-ADysthymic 0.6 (1.0) 1.8 (1.5) 3.7 (1.8)

Cliff'd=0.51 (0.37–0.62) Cliff'd=0.87 (0.80–0.93)Cyclothymic 1.4 (1.2) 4.7 (1.6) 8.7 (1.6)

Cliff'd=0.87 (0.76–0.93) Cliff'd=0.99 (0.96–1.00)Hyperthymic 2.6 (1.8) 2.7 (1.8) 3.7 (1.7)

Cliff' d=0.01 (−0.14–0.16) Cliff'd=0.34 (0.14–0.52)Irritable 0.2 (0.5) 1.6 (1.4) 2.3 (1.8)

Cliff'd=0.64 (0.52–0.74) Cliff'd=0.73 (0.62–0.81)Anxious 0.7 (0.7) 1.4 (1.1) 1.8 (1.0)

Cliff'd=0.40 (0.26–0.53) Cliff'd=0.61 (0.47–0.73)

Latent Class I, corresponding to the baseline class with low endorsing of TEMPS-A items was used as a referent term.Confidence intervals not including unity indicate statistical significance (pb0.05). Significant results in bold.

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the BIC, but in this solution a class with high endorsement onthe dysthymic and the anxious items and a moderate to lowendorsement on the cyclothymic and hyperthymic items wasfound, distinct from a class with high endorsement on allTEMPS-A items (the putatively “bipolar disorder” class), andanother class with moderate endorsement on most but not allTEMPS-A items (a putatively “risk for minor mood and anxietydisorders” class) (data available on request).

In our study, the results of a multinomial logistic regressionmodel indicated that greater involvement in creative activitiesrather than being a creative achiever best differentiated thoseinto the “risk for bipolar spectrum” class from the other classes.

Enhanced involvement in pleasurable activities – as creativeactivities might be – is a feature of both hypomania and mania.Greater involvement in creative activities might lead toincreased productivity, but the dispersion of energies that thisimplies might decrease overall chances of success. Indeed, paststudies found that creative achievement results from acombination of originality, talent, and passion mixed withsustained effort and persistence (Feist, 1998; Schuldberg, 2001).

A bipolar temperament might negatively affect creativity,despite increasing involvement into creative activities. Thismight explain why creative involvement rather than achieve-ment differentiates the “risk for bipolar spectrum” class fromthe other classes in this sample, a finding that is coherent withpast evidence indicating that hypomania rather than full maniais associated to creativity, while more severe expressions ofsymptoms may negatively influence creative accomplishment(Akiskal and Akiskal, 1988; Richards et al., 1988; Simeonova etal., 2005). It should also be noted that the sample includedstudents, who had scarce opportunity to achieve full evidenceof creative success.

Creative students in this study were involved in the arts.There is some evidence that the links between creativity andpsychopathology are confined to the arts and are less evident orabsent in the domain of sciences and technology (reviewed inAkiskal and Akiskal, 2010; Simonton, 2009). Therefore ourfindings cannot be extended to people involved in sciencebefore specific testing in the domain of scientific and techno-logical creativity.

The main limitation of our study is the use of self-reportmeasures to evaluate both creative involvement and achieve-ment and the risk of psychopathology. Both the GHQ-12 (Politiet al., 1994) and the TEMPS-A (Akiskal and Akiskal, 2005a)were proved to be valid and reliable as far as the construct theymeasure is concerned. This study also provided evidence thatthe CAQ can differentiate students professionally involved increative activities from students who are pursuing a courseleading to a profession principally requiring the application ofrules, extending past findings on its validity (Carson et al.,2005). Therefore we are confident that the links we observedare reproducible with adequate sample size. However, studyconstraints (the need of recruiting a large sample) precludedthe use of a standardized interview to specifically test thepresence of clinical diagnoses in this supposedly non-clinicalsample, nor didwe expose participants to validated tests aimedat measuring their creative potential, as in past studies(Richards et al., 1988; Santosa et al., 2007). Moreover, GHQassesses only current (past 4 weeks) psychological distress andtherefore did not capture mood disorder patients who wereeuthymic at the time of the study.

In conclusion, this study confirms that the cyclothymicdimension of the bipolar spectrum is linked to creativity, andthis link is likely to result from increased involvement intopleasurable activities, including creative ones.Whether greaterinvolvement in creative activities is a requisite to achievesuccess in people with temperament within the bipolarspectrum remains an open question. One possible mediatingvariable worth pursuing that might underlie success amongcyclothymic artists is obsessive–compulsive traits (Akiskal etal., 2005a,b).

Role of funding sourceResearch was supported by internal funds only.

Conflict of interestAuthors declare that to the best of their knowledge they have no conflicts

of interest to declare concerning the results of this study.

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