Gene flow by selective emigration as a possible cause for personality differences between small islands and mainland populations

Whether personality differences exist between populations is a controversial question. Even though such differences can be measured, it is still not clear whether they are due to individual phenotypic responses to the environment or whether they have a genetic influence. In a population survey we compared the personality traits of inhabitants of an Italian archipelago (the three Egadi islands; N = 622) with those of the closest mainland population (Trapani area; N = 106) and we found that personality differences between small populations can be detected. Islanders scored significantly lower on the personality traits of openness to experience and extraversion and higher on conscientiousness. We suggest that these personality trait differences could be an adaptive response to a confined socio‐environmental niche, genetically produced by a strong, non‐random gene flow in the last 20–25 generations, rather than the flexible response of islanders to environmental variables. To test this hypothesis, we compared subsets of the islander population classified by ancestry, birthplace, immigration and emigration and found that differences in extraversion can be accounted for by gene flow, while openness to experience and conscientiousness can also be accounted for by some gene–environment interactions. We propose a Personality Gene Flow hypothesis suggesting that, in small isolated communities, whenever there is strong, non‐random emigration, paired with weak and random immigration, we can expect rapid genetic personality change within the population. Copyright © 2010 John Wiley & Sons, Ltd.     

Perception of intersensory synchrony in audiovisual speech: not that special

Perception of intersensory temporal order is particularly difficult for (continuous) audiovisual speech, as perceivers may find it difficult to notice substantial timing differences between speech sounds and lip movements. Here we tested whether this occurs because audiovisual speech is strongly paired (“unity assumption”). Participants made temporal order judgments (TOJ) and simultaneity judgments (SJ) about sine-wave speech (SWS) replicas of pseudowords and the corresponding video of the face. Listeners in speech and non-speech mode were equally sensitive judging audiovisual temporal order. Yet, using the McGurk effect, we could demonstrate that the sound was more likely integrated with lipread speech if heard as speech than non-speech. Judging temporal order in audiovisual speech is thus unaffected by whether the auditory and visual streams are paired. Conceivably, previously found differences between speech and non-speech stimuli are not due to the putative “special” nature of speech, but rather reflect low-level stimulus differences.     

Personality and gang embeddedness

Gang membership can be transient or persistent, and most persons who participate in such groups at one point in their lives grow out of the lifestyle. The personality dynamics driving gang membership are poorly understood, although the five-factor model of personality has proved an effective way to understanding many types of antisocial behaviour. Using dichotomous self-nomination 152 remand and sentenced participants incarcerated within a general prison in London, UK indicated their gang embeddedness as youths, prior to custody, within prison, and as an intent following release. This enabled behavioural intention to be incorporated into the model as well as historical factors. Constructs derived from a variety of personality measures and constructs were used to predict overall reported gang embeddedness. These predictors reduced to two underlying dimensions: personal resilience and antisocial personality. Path analysis showed the antisocial personality dimension predicted previous convictions and degree of gang embeddedness, whereas resilience did not. The direct and indirect effects of the composite antisocial personality dimension explained 50% of the overall observed variance in gang embeddedness. We suggest that gang membership may reflect normal assortative processes within the members of such groups.     

Creativity and personality in professional dancers

In this study three different groups of professional dancers (ballet, modern/contemporary and jazz/musical), which considerably vary with respect to the creativity-related demands involved in the respective dancing style, are compared with respect to psychometrically determined creativity, general mental ability and different facets of personality. Results indicate that modern/contemporary dancers, who are often required to freely improvise on stage, exhibited relatively high levels of verbal and figural creativity (as it was measured by means of psychometric creativity tests), followed by jazz/musical and finally by ballet dancers. With respect to personality, modern/contemporary dancers can be characterized as being less conscientious, higher on psychoticism and more open to experiences than the remaining experimental groups. In line with relevant research in this field, this study reveals some central personality characteristics of highly creative individuals which may be considered as important ingredients in the acquisition or actualization of exceptional creative potential.     

Overclaiming as a measure of faking

Researchers have recently asserted that popular measures of response distortion (i.e., socially desirable responding scales) lack construct validity (i.e., measure traits rather than test faking) and that applicant faking on personality tests remains a serious concern ( [Griffith and Peterson, 2008] and [Holden, 2008]). Thus, although researchers and human resource (HR) selection specialists have been attempting to find measures which readily capture individual differences in faking that increase personality test validity, to date such attempts have rarely, if ever succeeded. The current study, however, finds that the overclaiming technique captures individual differences in faking and subsequently increases personality test score validity via suppressing unwanted error variance in personality test scores. Implications of this research on the overclaiming technique for improving HR selection decisions are illustrated and discussed.     

The general factor of personality: Questions and elaborations

Predictions from Rushton’s theory that a general factor of personality (GFP) has evolved based on effective social participation were examined in two large samples of adult Australian twins (5834 and 3672 individuals) and their relatives (8303 and 2677). General factors based on items and scales were compared to each other, across two different questionnaires, and between adults and adolescents. Behavior-genetic analyses based on the twin samples tested predictions comparing GFPs to scales with the GFP partialled out. Some support was found for Rushton’s theory, but the GFP was only marginally more heritable than the GFP-free scales and was not especially marked by the expected non-additivity of its genetic variance; moreover, the adult and adolescent GFPs showed substantial differences.     

Nonverbal emotion displays, communication modality, and the judgment of personality

The goal of this research was to investigate the impact of nonverbal expressive cues on the attribution of the Big Five personality traits. Expressive cues of fear, disgust, happiness, and sadness were elicited in a sample of 22 encoders while watching films, narrating, and posing. Encoders’ personalities were rated by themselves and unacquainted raters who watched the encoders, and blind judges rated the traits of a typical student. Expressive cues influenced the raters’ attribution of personality, but this influence was weakest when the encoders expressed happiness (vs. negative emotions) and when they were narrating an emotional experience (when the cues were least potent). Negative and strong expressive cues interfered with the application of a normative, and more accurate, judgment strategy.     

Are social networking profiles reliable indicators of sensational interests?

Sensational interests are sometimes reported on the personal profiles of social networking web sites such as Facebook. Can these reports be validated against established psychometric tools used by forensic psychologists? Given that web sites and personal profiles can be used as evidence of a person’s ‘character’ in legal contexts, evaluating their reliability and validity is important. This study evaluated the reliability of extracting data from the interests and activities sections of Facebook profiles, linking them to general personality and Sensational Interests Questionnaire (SIQ) scores. Data from 694 user profiles (N = 352 males) were linked to the Big Five personality traits, age, and educational attainment. Three independent raters coded the number of sensational topics reported by a user in each section. In Poisson regression analyses, higher SIQ Violent Occultism scores predicted a larger count of sensational interests, and sensational activities in males only. Higher SIQ Militarism scores predicted a larger number of sensational interests in males, but a smaller number in females. Although the number of sensational interests reported by social networking users on their personal profiles is potentially informative, further research should investigate gender differences, and why females with greater Militarism scores are less likely to report what these specific interests are.     

Big-Five personality factors, obesity and 2-year weight gain in Australian adults

The objective of this paper was to examine whether the Big-Five Personality factors were associated with obesity and 2-year weight gain in Australian adults. The sample included 5265 Australian adults aged 25-65 years. Binary logistic regression models indicated that Extraversion, Agreeableness and Neuroticism were cross-sectionally associated with obesity, with Conscientiousness inversely associated with obesity. The longitudinal analyses indicated that Extraversion predicted 2-year weight gain. The relationships between personality and obesity/weight gain were not moderated by age or sex. These results have potentially important implications for developing more effective treatment and prevention strategies for obesity.