Livia Veselka

Evidence for a heritable general factor of personality in two studies.

Two studies were conducted to see whether a general factor of personality (GFP) could be extracted from different measures of personality. Using samples of twins in both studies also allowed an assessment of the extent to which genetic and/ or environmental factors contributed to individual differences in the GFPs that were found. In Study 1, principal components analysis of the Big Five personality traits in combination with four scales of mental toughness yielded a strong GFP and behavior genetic model-fitting showed that individual differences in this GFP were fully accounted for by genetic and nonshared environmental factors. In Study 2, a GFP was extracted from the Big Five traits in combination with 15 facets of emotional intelligence. Individual differences in this GFP were also fully accounted for by genetic and nonshared environmental factors. These studies add to the growing body of research demonstrating the existence of a GFP and replicate one previous report of its heritability.

A general factor of personality: evidence from the HEXACO model and a measure of trait emotional intelligence.

The purpose of the present study was to determine if a general factor of personality (GFP) could be extracted from the six dimensions of the HEXACO model and four factors of trait emotional intelligence. Participants were 1,192 pairs of twins (666 MZ pairs, 526 DZ pairs) between the ages of 19 to 86 years, who completed the Trait Emotional Intelligence Questionnaire - Short Form and the HEXACO Personality Inventory - Revised. Principal components analysis yielded a strong GFP accounting for 33% of the variance, on which all variables with the exception of honesty-humility from the HEXACO showed moderate to large loadings. Behavioral genetic (BG) analyses revealed that individual differences in the GFP were entirely attributable to additive genetic and non-shared environmental factors - results that are in accord with previous BG analyses of a GFP. The present study adds to the body of evidence in support of a heritable GFP but an alternative perspective is also discussed.

Laughter and resiliency: A behavioral genetic study of humor styles and mental toughness

This study investigated phenotypic correlations between mental toughness and humor styles, as well as the common genetic and environmental effects underlying these correlations. Participants were 201 adult twin pairs from North America. They completed the Humor Styles Questionnaire, assessing individual differences in two positive (affiliative, self-enhancing) and two negative (aggressive, self-defeating) humor styles. They also completed the MT48, measuring individual differences in global mental toughness and its eight factors (Commitment, Control, Emotional Control, Control over Life, Confidence, Confidence in Abilities, Interpersonal Confidence, Challenge). Positive correlations were found between the positive humor styles and all of the mental toughness factors, with all but one reaching significance. Conversely, negative correlations were found between all mental toughness factors and the negative humor styles, with the mental toughness factors of Control, Emotional Control, Confidence, Confidence in Abilities, and Interpersonal Confidence exhibiting significant correlations. Subsequent behavioral genetic analyses revealed that these phenotypic correlations were primarily attributable to common genetic and common non-shared environmental factors. The implications of these findings regarding the potential effects of humor styles on wellbeing, and the possible selective use of humor by mentally tough individuals are discussed.

Survival of the scheming: A genetically informed link between the Dark Triad and mental toughness.

The present study is the first behavioral genetic investigation of the Dark Triad traits of personality, consisting of Machiavellianism, narcissism, and psychopathy, and the variable of mental toughness, reflecting individual differences in the ability to cope when under pressure. The purpose of this investigation was to explore a potential explanation for the success of individuals exhibiting the Dark Triad traits in workplace and social settings. Participants were adult twins who completed the MACH-IV, the Narcissistic Personality Inventory, and the Self-Report Psychopathy Scale assessing Machiavellianism, narcissism, and psychopathy, respectively, as well as the MT48, measuring mental toughness. Correlational analyses of the data revealed significant positive phenotypic associations between mental toughness and narcissism. Psychopathy and Machiavellianism, however, both showed some significant negative phenotypic correlations with mental toughness. Bivariate behavioral genetic analyses of the data were conducted to assess the extent to which these significant phenotypic correlations were attributable to common genetic and/or common environmental factors. Results indicate that correlations between narcissism and mental toughness were attributable primarily to common non-shared environmental factors, correlations between Machiavellianism and mental toughness were influenced by both common genetic and common non-shared environmental factors, and the correlations between psychopathy and mental toughness were attributable entirely to correlated genetic factors. Implications of these findings in the context of etiology and organizational adaptation are discussed.

A behavior genetic analysis of trait emotional intelligence and alexithymia: a replication.

This replication study examines relations between alexithymia and trait emotional intelligence (trait EI) at the phenotypic, genetic, and environmental levels. A sample of 1,444 same-sex twin pairs (850 MZ pairs and 594 DZ pairs) completed the Toronto Alexithymia Scale-20. A subset of 494 same-sex twin pairs (287 MZ pairs and 207 DZ pairs) had earlier completed the Trait Emotional Intelligence Questionnaire. Individual differences in alexithymia were attributable to genetic, non-shared environmental, and shared environmental factors. All but one of the facets of alexithymia were negatively and significantly correlated with the factors of trait EI, and these phenotypic correlations were entirely attributable to correlated genetic and correlated non-shared environmental factors. These bivariate results provide a valuable replication of those of Baughman et al. (Twin Research and Human Genetics, Vol. 14, 2011, pp. 539-543), which was conducted with substantially smaller samples of twins.

A behavioral genetic study of humor styles in an Australian sample

The present study investigated the extent to which individual differences in humor styles are attributable to genetic and/or environmental factors in an Australian sample. Participants were 934 same-sex pairs of adult twins from the Australian Twin Registry (546 monozygotic pairs, 388 dizygotic pairs) who completed the Humor Styles Questionnaire (HSQ). The HSQ measures four distinct styles of humor - affiliative, self-enhancing, aggressive, and self-defeating. Results revealed that additive genetic and non-shared environmental factors accounted for the variance in all four humor styles, thus replicating results previously obtained in a sample of twins from the United Kingdom. However, a study conducted with a U.S. sample produced different results and we interpret these findings in terms of cross-cultural differences in humor.

A behavioral genetic analysis of alexithymia and the Dark Triad traits of personality.

The present study is the first to assess phenotypic correlations between alexithymia and the Dark Triad traits of personality in a community sample, as well as the common genetic and environmental factors underlying these correlations. Participants were 232 North American adult twin pairs who completed the Narcissistic Personality Inventory, the Self-Report Psychopathy Scale, the MACH-IV, and the Toronto Alexithymia Scale. Results revealed that alexithymia correlates significantly and positively with psychopathy and Machiavellianism, and negatively with narcissism. Subsequent bivariate behavioral genetic analysis demonstrated that these phenotypic correlations were primarily attributable to common genetic and common non-shared environmental factors. The implication of these findings regarding the maladaptive functions of alexithymia within the antisocial realm of behavior and the need for replication are discussed.

A Comparison of the Construct Validity of Two Alternative Approaches to the Assessment of Psychopathy in the Community

This study compared the validity of 2 different self-report approaches to the assessment of psychopathy in nonforensic samples: the Psychopathy Resemblance Index (PRI), derived from a measure of normal personality functioning, and the Self-Report Psychopathy Scale (SRP), developed specifically to assess the maladaptive traits associated with psychopathy. In 2 adult samples (n 1 = 260, n2 = 250), the PRI and the SRP were positively correlated with each other and with measures of maladaptive personality traits related to Machiavellianism and narcissism. However, unlike the SRP, the PRI was independent of trait empathy and general psychopathology and was positively associated with trait emotional intelligence. These results suggest that the PRI captures a more adaptive variant of psychopathy than does the SRP.

Phenotypic and Genetic Relations Between the HEXACO Dimensions and Trait Emotional Intelligence

The present study investigated the location of trait emotional intelligence (trait EI or trait emotional self-efficacy) within the context of the HEXACO model - a more comprehensive personality framework than the conventional Big Five structure. A total of 666 MZ and 526 DZ adult twin pairs from the United Kingdom completed the short form of the Trait Emotional Intelligence Questionnaire (TEIQue-SF) and the short form of the HEXACO Personality Inventory (HEXACO-60). Many significant phenotypic correlations between the TEIQue-SF and the HEXACO-60 were obtained, which were strongest for HEXACO Extraversion, and weakest for HEXACO Honesty-Humility. As was expected, Emotionality was the only HEXACO dimension to correlate negatively with TEIQue-SF scores. Bivariate behavioral genetic analyses revealed that all phenotypic correlations were attributable to common genetic and common nonshared environmental factors. The study confirms the validity of trait EI as a constellation of emotional self-perceptions located at the lower levels of personality.

Emotion and behavior: a general factor of personality from the EAS Temperament Survey and the Strengths and Difficulties Questionnaire.

The mothers of 603 pairs of 3- to 13-year-old twins in Korea completed the Emotionality, Activity, Sociability (EAS) Temperament Survey and the Strengths and Difficulties Questionnaire in reference to their twins. Principal factor analysis of the seven scales comprising these measures yielded a general factor on which all the scales had moderate to large loadings. Univariate behavioral genetic analyses showed that individual differences on this general factor could best be accounted for by additive genetic and non-shared environmental effects, with a heritability of 53%. The results strengthen the construct validity of the general factor of personality (GFP) by extracting this higher-order dimension from disparate measures, and have implications regarding social desirability criticisms applied to the GFP theory.