Should the space of basic personality traits be extended to include the disposition toward psychotic-like experiences ?

Previous research has shown that there is a latent disposition toward psychotic-like experiences in the general population, labeled schizotypy. However, there is a dispute over the conceptual status of schizotypy: does it represent merely psychosis proneness, or is it a broad and general personality trait? If a disposition should be regarded even as a candidate for a personality trait, its scores would probably be distributed normally in the population and it must show irreducibility in regard to the previously discovered personality traits. In this research, these questions are addressed, using the construct of Disintegration as an operationalization of schizotypy. The results show that although some modalities of Disintegration have skewed distributions in the student sample (N=345, 65% female), the global Disintegration scores have a normal distribution. Furthermore, Disintegration modalities constitute a latent component which is distinct from the personality traits that form HEXACO model of basic personality structure. Nevertheless, Disintegration shares some variance with the HEXACO traits, especially with the negative poles of Extraversion and Conscientiousness. The results suggest that a conceptual view of a schizotypy as a personality trait is at least plausible and they can be used as guidelines for future empirical studies of this problem.

number of individuals and in their nature they are supposed to be qualitatively different from the experiences of persons who do not suffer from mental dysfunctions.
However, empirical research of the external correlates of basic personality traits has shown that those traits could be dispositions toward mental maladaptations too.For example, the trait of Neuroticism, which is present in several models of the basic personality structure (Eysenck & Eysenck, 1964;Costa & McCrae, 2008;Zuckerman, 2002), has proved to be a good predictor of psychological dysfunctions which are neurotic in their nature.There is a similar proposal for psychotic symptoms.Empirical data show that psychoticlike experiences are present in the general population too (van Os, Linscott, Myin-Germeys, Delespaul, & Krabbendam, 2009).This framework imposes a disposition toward psychotic-like experiences which is present in all individuals, while only smaller proportions of people develop full psychotic symptomatology.It is reflected in a specific personality and behavioral pattern called schizotypy (Lenzenweger, Maher, & Manschreck, 2005;Lenzenweger, 2006).The construct of schizotypy implies that a disposition towards psychotic-like experiences is dimensional and not taxonic in its nature, and there are some empirical data to support this view (Rawlings, Williams, Haslam, & Claridge, 2008), but the debate on the proposed dimensionality of schizotypy is still unresolved (Beauchaine, Lenzenweger, & Waller, 2008;Rawlings, Williams, Haslam, & Claridge, 2008a;Linscott, Allardyce, & van Os, 2010).
The hypothesis about the existence of psychotic-like experiences in the general population could be very useful in understanding psychosis and schizophrenia, and for the prevention of these illnesses too.This is the main reason why the concept of schizotypy is given much attention in the scientific community.There is a large amount of empirical data, validating psychosis proneness.First of all, schizotypal traits are a significant predictor of overall mental health, although this relation is complex and involves not only linear, but also curvilinear relationships (Goulding & Odehn, 2009).Schizotypy also correlates with social dimensions of autistic traits, confirming the hypothesis of relatedness of autistic and psychotic phenomena (Russell-Smith, Maybery, & Bayliss, 2011).Kaczorowski, Barrantes-Vidal, & Kwapil (2009) showed that negative aspects of psychosis proneness (social and physical anhedonia) are related to neurological soft signs of deficits in sensory integration, motor coordination and motor sequencing.This research supports not only the hypothesis that schizotypy is a valid construct for the exploration of schizophrenia spectrum disorders, but also the existence of subclinical psychotic experiences in the general population.Finally, persons with frequent psychosis-like experiences have difficulties in recalling the memories from the declarative memory (Hoshi, Scoales, Mason, & Kamboj, 2011), their social functioning is affected by impairments in emotional intelligence (Aguirre, Sergi, & Levy, 2008), and they are more prone to obsessive-compulsive disorder and dissociative symptoms (Chmielewski & Watson, 2008).
However, there are views of schizotypy not just as psychosis proneness, but more as a broad personality trait, which explains variation in many forms of behavior in individuals without psychological dysfunctions (Clarigde, 2010).The data that confirm relations of schizotypy with various kinds of non-clinical traits and behavior are in accordance with this view.Previous findings show that psychotic-like behaviors are related to insecure attachment styles (Berry, Band, Corcoran, Barrowclough, & Wearden, 2007), creative (Nelson & Rawlings, 2010) and aggressive behavior (Nederlof, Muris, & Hovens, 2012).There were several attempts to explore the connections between schizotypy and basic personality traits, mostly from the space structured by five broad personality factors derived from a lexical paradigm (Costa & McCrae, 2008).Those studies show that schizotypy has the strongest relations to the traits of Neuroticism and low Agreeableness (Asai, Sugimori, Bando, & Tano, 2011).Positive schizotypal markers, like Magical Ideation and Perceptual Aberration are related to Openness to experience, while negative symptoms have negative relations to Openness and Extraversion (Ross, Lutz, & Bailey, 2002).However, the question of crucial theoretical significance is: are schizotypal dispositions reducible to basic personality traits?If they are, schizotypy could not be regarded as an autonomous construct, but a combination of dysfunctional basic personality traits.There is some evidence that the measures of dissociative experiences (Kwapil, Wrobel, & Pope, 2002) and personality disorders (Andersen, 2000) fall out of the space defined by the Five Factor Model.Watson, Clark, & Chmielewski (2010) explicitly claim that schizotypy can be conceptualized as a basic personality trait that cannot be reduced to descriptive personality dimensions, and that it is conceptually identical to the evaluative trait called Oddity, discovered in recent lexical research (Simms, Yufik, Thomas, & Simms, 2008).However, Ashton & Lee empirically show that schizotypy cannot be equal to Oddity, because the latter shares most of its variance with Openness to experience (Ashton & Lee, 2012).Nevertheless, in this research schizotypy has also been found to be outside the space described by basic personality traits, but the authors interpret schizotypy rather as psychosis proneness, than a broad personality trait.

Disintegration
Recently, a new operationalization of the model of schizotypy has been proposed (Knežević, Opačić, Kutlešić, & Savić, 2005).It originated as a reconceptualization of Psychoticism as a basic personality trait (Eysenck & Eysenck, 1976).The construct is called Disintegration and it is derived from a factor analysis of 26 scales that measure psychotic and schizotypal experiences.The construct is constituted of ten modalities which are subordinate traits to the general factor of Disintegration: General executive dysfunction (dysregulation of attention, planning, memory, emotional reactions etc.), Perceptual distortions (depersonalization and derealization), Increased awareness (synesthesia, responsiveness to aesthetic stimuli), Depression (pronounced feelings of sorrow, loneliness, self-pity etc.), Paranoia (suspicion, distrust, ideas of persecution and the impression of conspiracy), Mania (elevated mood, high activity, extreme optimism etc.), Social anhedonia (shyness, preference for solitude, lack of the need to make friends), Flattened affect (emotional indifference, numbness, affective superficiality), Somatoform dysregulation (sensory and motor conversions, the impression of a change of internal organs, insensitivity to pain, and the feeling of corporal numbing) and Magical thinking (belief in telepathy, illogical thinking, superstition, etc.).Although the research involving the concept of Disintegration is still in its infancy, there are some empirical data that confirm the validity of its construct.Disintegration traits are more highly pronounced in visual artists (Međedović & Đorđević, 2011) and Disintegration can predict stabile forms of criminal behavior (Međedović, Kujačić & Knežević, 2012).It has also been found that Disintegration modalities are related to Anxiety and Avoidance, as dimensions of romantic adult attachment (Želeskov-Djorić & Međedović, 2011).
There is at least one obvious advantage of Disintegration as an operationalization of psychotic proneness: its broadness and comprehensiveness.Most of the schizotypy models are comprised of two (Kwapil, Ros-Morente, Silvia, & Barrantes-Vidal, 2012), three (Compton, Goulding, Bakeman, & McClure-Tone, 2009) or four (Mason & Claridge, 2006) factors.When ten modalities of schizotypal experiences are measured, Disintegration has a potential to provide more detailed information on the characteristic of psychosis proneness.

Goals of the present study
This study is aimed to explore several questions regarding the construct of Disintegration and schizotypy in general.First, the distribution of Disintegration in the student sample will be explored.Normality of the distribution is not the necessary condition to treat schizotypy as a personality trait (Micceri, 1989), however, if Disintegration has a normal distribution it would support its trait-like interpretation.Second, the question of irreducibility of Disintegration to basic personality traits will be addressed.If Disintegration is a distinct trait with its own specific content, it will not be located in a latent space of the already established personality traits.The model of the basic personality structure which is chosen for this analysis is comprised of six broad dimensions derived from a lexical paradigm: the HEXACO personality framework (Ashton, Lee, Perugini, Szarota, de Vries, Di Blas, Boies, & De Raad, 2004).HEXACO is a revised and extended model of personality, compared to the Big Five structure and its space is described by six broad dimensions: Honesty/Humility, Emotionality, Extraversion, Agreeableness, Constiouentiousness and Openness to experience (Lee & Ashton, 2008).In addition, the relations between the Disintegration modalities and HEXACO domains and facets will be explored in this study.

Method Sample and procedure
The participants in this research were selected from the population of students (N=345; 65% female; the mean age of the participants: 21) studying at various faculties of Singidunum University and the University of Belgrade.All students filled in the questionnaires on a voluntary basis.They received additional credits on the psychology courses they attended at their faculties as a motivation for participating in the research.Filling in the questionnaires lasted for forty minutes on average.

Measures
Disintegration was measured with DELTA-10 inventory (Knežević et. al., 2005).It explores ten modalities of schizotypal experiences (General executive dysfunction, Perceptual distortions, Enhanced awareness, Depression, Paranoia, Mania, Social anhedonia, Flattened affect, Somatoform disregulation and Magical thinking) providing a score of the general trait of Disintegration too.DELTA10 inventory has 113 items, with 30 items scored reversely for the purpose of an acquiescence control.
Six factors found in the recent emic lexical research of personality structure were measured with HEXACO-PI-R inventory (Lee & Ashton, 2004;2006).This instrument measures six broad domains of personality and 24 subordinate facets, four for every domain: Honesty/Humility (Greed-Avoidance, Fairness, Sincerity and Modesty), Emotionality (Dependence, Anxiety, Sentimentality and Fearfulness), Extraversion (Liveliness, Sociability, Social Self-Esteem and Social Boldness), Agreeableness (Patience, Forgiveness, Gentleness and Flexibility), Conscientiousness (Diligence, Prudence, Perfectionism and Organization) and Openness (Creativity, Aesthetic Appreciation, Unconventionality and Inquisitiveness).The questionnaire has 100 items, sixteen for each domain and four for each facet trait.The interstitial trait of Altruism was not included in the analysis.
Both instruments are based on a Likert-type scale for answering the questionnaire items.The scale ranges from 1 to 5, where 1 means "I disagree completely" and 5 "I agree completely".

Characteristics of the Disintegration scales and the scores obtained on them
In this analysis the reliabilities of the scales measuring Disintegration traits are explored.Means and standard deviations of scales are provided as well.But the most important analysis is the exploration of the normality of the distributions of Disintegration measures.Kolmogorov-Smirnov test (Wilcox, 1998) was used for this purpose.The results of this analysis are shown in Table 1.As it can be seen in Table 1, all of the Disintegration scales have reliabilities above α=.70,which indicates that they are reliable instruments for measuring the schizotypal traits.The tests of normality of the Disintegration scores detect four measures, the scores of which significantly deviate from normal distributions: Depression (KSz=2.46;p<.01), Somatoform dysregulation (KSz=1.91;p<.01), Perceptual distortions (KSz=1.82;p<.01) and Paranoia (KSz=1.55;p<.05).The means of these scales (column 3) are below 2, suggesting that distributions are skewed toward the lower scores of the scales.Because of the fact that these four modalities of Disintegration do not have normal distribution, all other analyses are performed using standardized and normalized scores of the examined variables.The variables are normalized utilizing the Rankit method, because it has proven to have the best performance of most of the normalizing methods (Solomon & Sawilowsky, 2009).

Location of Disintegration in the space of HEXACO facets
Testing the possible distinctiveness of the Disintegration modalities in regard to lexical personality traits, a Principal Axis Factoring was performed.This method was chosen because there was a clear hypothesis about the latent structure of the examined space, set on the previous empirical findings (Ashton & Lee, 2012).From the shared space of Disintegration modalities and HEXACO facets, all latent factors that had eigenvalues greater than 1 were extracted.Using this method, seven factors were obtained.This solution was confirmed by the optimized method of parallel analysis (Timmerman & Lorenzo-Seva, 2011).The factors were then rotated into the Varimax position.These are their empirical eigenvalues, random eigenvalues derived from parallel analysis (in parentheses) and percentage of explained variance, respectively: 6.76 (1.62), 19.89%; 3.28 (1.55), 9.66%; 2.97 (1.48), 8.73%; 2.76 (1.43), 8.16%; 2.11 (1.38), 6.21%; 1.85 (1.34), 5.41% and 1.34 (1.30); 3.66%.The pattern matrix of the extracted factors is shown in Table 2.As it can be seen in Table 2, the first factor extracted in PAF represents Disintegration.Other factors clearly represent six domains of the HEXACO personality model.All of the Disintegration modalities are loaded on the first latent dimension except Social anhedonia which should be regarded as an Extroversion facet (-.80), located on its negative pole.Depression also has a very strong loading on Extraversion (-.50).General executive dysfunction has a secondary loading on the negative pole of Conscientiousness (-.30).Enhanced awareness has a secondary loading on the factor of Openness to experience (-.35), while Flattened affect is partially located on the negative pole of Emotionality (-.45).

Relations between modalities of Disintegration and HEXACO facets
In order to gain more precise and detailed information on the relationship between basic personality traits and Disintegration, bivariate correlations between the modalities of Disintegration and the facets of the HEXACO domains are analyzed.As a measure of association, Pearson's coefficient of linear correlation is used.The results of the correlation analysis are presented in Table 3.A brief look at Table 3 tells that Disintegration shares some variance with various facets of the HEXACO personality space.Disintegration correlates negatively with Conscientiousness (r=-.39;p<.01), Extraversion (r=-.35;p<.01) and Honesty (r=-.28;p<.01) factors.There is a positive correlation with Emotionality (r=.20; p<.01); the correlation with Agreeableness is very low (r=-.11;p<.05), while there is no correlation between the general factor of Disintegration and the domain of Openness (r=.02; p>.05).

Discussion
The aim of this research was not to answer on the question presented in its title.One of the reasons is that the question has its theoretical and conceptual implications and the answer would depend on the criteria that various authors have about the fundamental characteristics of personality traits.However, the goal of this article is to draw attention on the empirical aspects of the problem and to facilitate empirical research as a strategy of resolving it.Three questions related to the problem are examined in this research: distributions of Disintegration scales, distinctiveness from already conceptualized personality traits and relations with them.The sample of respondents that participated in this research is far from representative, but it can help to derive some conclusions on the conceptual status of Disintegration as an operationalization of schizotypy.The main conclusion that can be made from the results of the normality tests performed on the Disintegration scales (Table 1) is that the measure of the general factor of Disintegration distributes normally in the examined sample (KSz=.62;p>.05).However, there are some modalities of Disintegration that are skewed on the lower scores of the scales used in the research.These are Depression (KSz=2.46;p<.01), Somatoform dysregulation (KSz=1.91;p<.01), Perceptual distortions (KSz=1.82;p<.01) and Paranoia (KSz=1.55;p<.05).The interpretation of the deviation from the normal distribution of these scales must be performed with caution.There are at least two main reasons for the skewness: 1.The first is conceptual in nature -distributions of these four modalities are skewed because the measured phenomena are too rare in the examined sample.This reason is called "conceptual" because the possible rareness of these specific traits in nonclinical, student sample could mean that experiences that constitute those traits exist only in clinical populations.An empirical test of this hypothesis must involve persons from clinical population as research subjects.Taxometric analysis of these four Disintegration scales would also provide important data regarding this question.2. The second reason is psychometric -the scales used to measure these phenomena are not discriminative for the whole continuum of the examined trait.However, for the modalities of Somatoform dysregulation and Perceptual distortions, non-normal distributions could be expected.These are differential-diagnostic symptoms of psychotic mental states, and they are considered rare in the subclinical population (Simeon, 2004).Similar could be said for Paranoia.But it is interesting that a trait of Depression, which comprises many models of normal personality structure (Smederevac, Mitrović, & Čolović, 2010;Costa & McCrae, 2008), has a skewed distribution.It can be hypothesized that the intensity of the depressive states as indicators of psychoticlike experiences are higher than the ones usually found in conceptualizations of Depression as a general personality trait.That could be the reason for the skewed distribution of the Depression modality.Nevertheless, most of the Disintegration modalities, including the general score on the trait are distributed normally in the sample.This finding is congruent with the dimensional views of schizotypy (Rawling et al., 2008;van Os et al., 2009) and supports a possibility that it could be considered as a personality trait.
Factor analysis is performed to examine if the schizotypal modalities are already represented in basic personality traits, probably as their maladaptive features (Asai et al., 2011).The results of PAF show that Disintegration cannot be reduced to six lexical traits: the markers of psychotic-like experiences are not represented in the HEXACO model (Table 2).This finding is congruent with the previous data of a latent structure of the space described by schizotypy and personality traits (Watson et al., 2010;Ashton & Lee, 2012).This finding confirms that disposition toward psychological dysfunctions is broad and heterogenous disposition, which is similar with the view of Psychoticism trait, provided by Hans Eysenck (Eysenck & Eysenck, 1976).Furthermore, this disposition is qualitatively different than personality traits described in the revised lexical model of personality, and can not be reduced on them (Ashton & Lee, 2012).This imply the conclusion that assessing the "normal" personality traits is insufficient for detecting the proneness for psychotic and psychotic-like experiences.Having in mind the comprehensiveness of psychotic proneness, our understanding of the basic sources of human individual differences can not be profound without including schizotypy in empirical research, beside "normal" personality traits.
Although Disintegration is distinct from HEXACO traits, there is important amount of shared variance between them.This suggests that some aspects of psychological dysfunctions can emerge from personality (Wright, Pincus, & Lenzenweger, 2012), probably if person have very high or low scores on personality traits.PAF and the correlation analysis (Tables 2 and 3) provided some additional data about the relationships between the examined constructs.The results of these two analyses are mutually congruent, so they will be analyzed together.In regard to PAF, secondary loadings of the Disintegration modalities on personality factors are important for understanding the relations between schizotypy and personality traits.There is one modality of Disintegration which in fact is a part of the HEXACO space: Social anhedonia.It is located on the negative pole of the Extraversion factor and correlates with all of the Extraversion facets (Table 3), but most intensively with Sociability (r=-.69;p<.01).
One of the unexpected findings is the loading of the Depression modality onto the negative pole of Extraversion (Table 2).One could hypothesize that Depression would be connected to the Emotionality factor, where the traits of negative affects like Anxiety and Fearfulness are placed (Lee & Ashton, 2006).This finding shows that Depression (conceptualized as a schizotypy modality) is more associated with Introversion than Emotionality, which emphasizes the differences between Neuroticism from the Five Factor Model (Costa & McCrae, 1992) and Emotionality from the HEXACO structure.Obviously, Neuroticism and Emotionality differences are not based only on the presence of the angerrelated content (Ashton, Lee, Visser, & Pozzebon, 2008): FFM Neuroticism also includes depressive indicators, while they are not associated with the HEXACO Emotionality.The link between Depression and Extraversion can be explained most optimally (Table 3) by the correlations between Depression and Social Self-Esteem (r=-.51;p<.01) and Liveliness (r=-.50;p<.01).Depressive states are associated with the lack of self confidence in social interactions and low activity in general.
The personality factor of Constiouentiousness is described by the satisfactory control of the impulses and the ability to plan ahead and organise behavior according to the previously established goals (MacCann, Duckworth, & Roberts, 2009).These abilities are based on the integrated functioning of executive processes (Pietrzak, Sprague, & Snyder, 2008).Secondary loadings of General executive dysfunction on the factor of Constiouentiousness (-.30) strongly confirm those previous findings (Table 2).Furthermore, correlation analysis (Table 3) reveals that GEI facet of Disintegration correlates most highly with Diligence (r=-.44;p<.01) and Prudence (r=-.44;p<.01) which are the traits that describe the tendency for hard work and non-impulsive behavior.
Flattened affect as a Disintegration modality was partly located on the negative pole of the Emotionality factor (.-40; Table 2).This was highly expected, because the low pole of this factor is conceptualized by lack of empathy and detachment from other people, absence of fear and anxiety (Lee & Ashton, 2006).This finding is in accordance with the relations of the Emotionality negative pole with Callous Affect as an aspect of subclinical psychopathy (Međedović, 2011).This relation of shallow and constricted affect and low Emotionality is the most highly pronounced through the correlation between Flattened affect and Sentimentality (r=-.31;p<.01;Table 3).
Finally, Enhanced awareness, a trait very similar to the Absorption from Tellegen's model of personality (Patrick, Curtin, & Tellegen, 2002) has a secondary loading on the Openness factor (.35; Table 2).This finding confirms the previous data on the relationship between Openness and Absorption (Tellegen & Waller, 2008).Its relations with Creativity (r=.34; p<.01;Table 3) are congruent with the previously established relations of Enhanced awareness and Openness in a group of painters (Međedović & Đorđević, 2011).However, the absence of the correlation between Disintegration and the domain of Openness (r=.02; p>0.5) is not consistent with some of the previous findings that link Openness and schizotypy (Asai et al., 2011;Ross et al., 2002).The present data suggest that Openness is related to the adaptive and creative potentials in schizotypy and not to the dysfunctional aspects of psychosis proneness.

Limitations and future directions
The most serious limitation of this research is the structure of the sample.The goal of the research was to explore schizotypy and its relations with personality traits in non-clinical population, but university studensts are highly selected individuals which can not represent adequately general population in several ways.It is necessary to replicate these findings in more heterogeneus community sample, but in clinical population too.Irreducibility of Disintegration on the "normal" personality traits is supposed to be replicated, because previous research have come to this conclusion too (Watson, Clark, & Chmielewski, 2010;Ashton & Lee, 2012), however it will be very important to examine the distributions of Disintegration scales in these samples too.New taxometric studies aimed to explore the dimensionality of the specific modalities of propsychotic features, not only the general score of the schizotypy, are necessary for the further understanding of the nature of schizotypy.
The lexical paradigm could be still used as a conceptual and methodological tool for the attempt to gain new knowledge of the schizotypy.Perhaps, an extended methodology should be used in future studies that could search for schizotypy in language: extensive search of all terms that could be candidates for the descriptors of psychosis proneness, according to the previous empirical findings or the existing theoretical concepts.Also, all types of terms should be analyzed: nouns, verbs and adjectives at least.An exact hypothesis could be formulated using the results of the present research: if the reason for the skewness of several Disintegration modalities is their rarity in general population, they probably would not be find in the language.Rareness in the expression and behavior could be the main reason for their low representation in language (Srivastava, 2010).Nevertheless, other, more benign modalities of the schizotypy could still be found in language and that could imply that schizotypy is not unitary construct in conceptual sense: some of its parts could be distinctively related to pathological processes which are rare and some could be more general and comprehensive.However, if this extended methodology does not provide any dispositions toward psychotic-like experiences once again (or some of its aspects), then that would be an important finding per se.It would indicate that schizotypy is, in fact, somewhat different in its nature from personality traits, and that would help in clarifying its conceptual status as a psychological construct.

Concluding remarks
In this research, several questions regarding the nature of schizotypy are addressed.The Disintegration trait, as a measure of psychosis proneness, has a normal distribution in the sample of student participants.However, there are some narrow schizotypal traits that do not have normal distribution; they are skewed to the lower scores of measuring scales.This could be explained by lower sensitivity of the scales to detect the variance on that part of the distribution, or the low frequency of specific psychotic-like experiences in the examined sample.
Schizotypy can be distinguished from the basic personality traits explored by the HEXACO model of the basic personality structure, all but one trait modality: Social anhedonia, which is part of the opposite pole of Extraversion domain (e.g.Introversion).There are other relations of psychotic-like experiences with personality traits, especially with the low Conscientiousness and Extraversion, but with other domains and facets of the HEXACO model too.They are conceptually expected, and in line with the previously established findings.Only the relations between psychosis proneness and Agreeableness and Openness (Asai et al., 2011;Ross et al., 2002) are not replicated in this research.However, the main finding is that schizotypy is distinct, broad and comprehensive disposition, irreducible to lexical personality traits.
The results presented in this study suggest that future research should explore the ability of schizotypy to predict external criteria beyond and above already established personality traits.To achieve this goal, researchers should administer schizotypy measures together with the operationalizations of the personality traits in future studies.This pragmatic strategy will help answering the question presented in the title of this paper in an empirical manner.

Table 2
Pattern matrix of extracted factors rotated in Varimax position