Using Dynamic Panel Models to Study Age‐related Differences and Time‐related Changes in Personality

Along with an increasing interest in the plasticity and role of personality across the adult lifespan comes the need for a diverse set of innovative statistical approaches to study it. With this paper, we set out to illustrate some of the possibilities and challenges in modelling age‐related differences and time‐related changes in personality psychology by means of dynamic panel models. To this end, we first distinguish between the study of age‐related differences and time‐related changes and demonstrate how the treatment of age and time as either discrete or continuous variables implies important modelling choices. Second, we present a selection of four example cases that address the topic of age moderation in diverse matters and with different objectives. Based on our cross‐tabulation of age and time as discrete and continuous variables, the first two example cases represent fairly well‐established models (cases A and B), whereas the remaining cases are used to illustrate current developments in the field (cases C and D). We close the paper with some final remarks on current limitation and future research directions. © 2019 European Association of Personality Psychology     

Event‐related potential differences in children supplemented with long‐chain polyunsaturated fatty acids during infancy

Long‐chain polyunsaturated fatty acids (LCPUFA) have been shown to be necessary for early retinal and brain development, but long‐term cognitive benefits of LCPUFA in infancy have not been definitively established. The present study sought to determine whether LCPUFA supplementation during the first year of life would result in group differences in behavior and event‐related potentials (ERPs) while performing a task requiring response inhibition (Go/No‐Go) at 5.5 years of age. As newborns, 69 children were randomly assigned to infant formulas containing either no LCPUFA (control) or formula with 0.64% of total fatty acids as arachidonic acid (ARA; 20:4n6) and various concentrations of docosahexaenoic acid (DHA; 22:6n3) (0.32%, 0.64% or 0.96%) for the first 12 months of life. At 5.5 years of age, a task designed to test the ability to inhibit a prepotent response (Go/No‐Go) was administered, yielding both event‐related potentials (ERPs) and behavioral data. Behavioral measures did not differ between groups, although reaction times of supplemented children were marginally faster. Unsupplemented children had lower P2 amplitude than supplemented children to both Go and No‐Go conditions. N2 amplitude was significantly higher on No‐Go trials than Go trials, but only for supplemented children, resulting in a significant Group × Condition interaction. Topographical analysis of the ERPs revealed that the LCPUFA‐supplemented group developed a novel period of synchronous activation (microstate) involving wider anterior brain activation around 200 ms; this microstate was not present in controls. These findings suggest that LCPUFA supplementation during the first 12 months of life exerts a developmental programming effect that is manifest in brain electrophysiology. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=oM2leg4sevs .     

Comparing Personality Test Formats and Warnings: Effects on criterion‐related validity and test‐taker reactions

The potential for applicant response distortion on personality measures remains a major concern in high‐stakes testing situations. Many approaches to understanding response distortion are too transparent (e.g., instructed faking studies) – or are too subtle (e.g., correlations with social desirability measures as indices of faking). Recent research reveals more promising approaches in two methods: using forced‐choice (FC) personality test items and warning against faking. The present study examined effects of these two methods on criterion‐related validity and test‐taker reactions. Results supported incremental validity for an FC and Likert‐scale measure in warning and no‐warning conditions, above and beyond cognitive ability. No clear differences emerged between the FC vs Likert measures or warning vs no‐warning conditions in terms of validity. However, some evidence suggested that FC measures and warnings may produce negative test‐taker reactions. We conclude with implications for implementation in selection settings.     

Motivational Basis of Personality Traits: A Meta‐Analysis of Value‐Personality Correlations

We investigated the relationships between personality traits and basic value dimensions. Furthermore, we developed novel country‐level hypotheses predicting that contextual threat moderates value‐personality trait relationships. We conducted a three‐level v‐known meta‐analysis of correlations between Big Five traits and Schwartz's (1992) 10 values involving 9,935 participants from 14 countries. Variations in contextual threat (measured as resource threat, ecological threat, and restrictive social institutions) were used as country‐level moderator variables. We found systematic relationships between Big Five traits and human values that varied across contexts. Overall, correlations between Openness traits and the Conservation value dimension and Agreeableness traits and the Transcendence value dimension were strongest across all samples. Correlations between values and all personality traits (except Extraversion) were weaker in contexts with greater financial, ecological, and social threats. In contrast, stronger personality‐value links are typically found in contexts with low financial and ecological threats and more democratic institutions and permissive social context. These effects explained on average more than 10% of the variability in value‐personality correlations. Our results provide strong support for systematic linkages between personality and broad value dimensions, but they also point out that these relations are shaped by contextual factors.     

Controlled Substance‐related Beliefs and Use: Relationships to Undergraduates' Creative Personality Traits

The relationship between creativity and various mind‐altering substances — especially alcohol — has been a popular topic among creativity researchers and the public at large. Yet experimental studies have found little evidence that alcohol use has a causal influence on creativity, with most studies of creative production showing negative or neutral effects. However, the impact of high levels of creativity on future alcohol use (i.e., the reciprocal relationship) has been rarely studied. The present study examined the relationship between creative personality characteristics, use of alcohol, tobacco, and marijuana, and alcohol‐related beliefs among 431 undergraduates. Results of correlational and t‐test analyses suggest that creative personality is not significantly correlated with use of these three controlled substances, and that the relationships between personality scores and self‐reported beliefs about alcohol are generally weak, with notable exceptions. The paper concludes with specific recommendations regarding research on the relationship between creativity and the use of controlled‐substances.     

Personality in Non‐human Animals

Over the past decade, research on animal personality has flourished in numerous disciplines ranging from Behavioral Ecology and Developmental Psychobiology to Genetics and Comparative Psychology. The broad appeal of animal studies is that, in comparison with human studies, they afford greater experimental control, more options for measuring physiological and genetic parameters, greater opportunities for naturalistic observation, and an accelerated life course. Past research has established that personality (a) exists and can be measured in animals; (b) can be identified in a broad array of species, ranging from squid, crickets, and lizards, to trout, geese, and orangutans; and (c) shows considerable cross‐species generality for some dimensions. The wave of new studies is shedding fresh light on traditional issues in personality research (How do early experiences affect adult personality?), raising novel questions (What are the evolutionary origins of personality traits?) and addressing practical problems (Which dogs are best suited to detecting explosives?).     

Personality and health‐protective behaviour

Over the last decades much research has been devoted to the analysis of psychosocial factors associated with the development of health problems. However, less attention has been paid to mechanisms explaining why people keep engaging in risky behaviours and do not develop, instead, those habits that could increase their quality of life. To answer these questions, two lines of research have been followed: the main hypothesis of the first line is that there are personality characteristics that predispose the development of certain patterns of behaviour. The second line is focused on the analysis of the psychological processes that, together with situational factors, explain what behaviour is initiated and how it is maintained or changed. The main purpose of this paper is to review these two lines of research: what their main contributions are and what the problems they face are. Copyright © 1999 John Wiley & Sons, Ltd.     

Personality and occupational markers of ‘solid citizenship’ are associated with having fewer children

Investigating associations between personality and reproductive fitness may reveal the adaptive significance of human behavioural traits. What we dub ‘solid-citizenship’ personality characteristics such as self-control, diligence and responsibility may repay study from an evolutionary perspective as they protect against negative life-outcomes. We explored associations between reproductive fitness and personality questionnaire markers of solid citizenship in 4981 women from four Australian samples. We also examined relations between reproductive fitness and army discharge status, an applied measure of solid citizenship, in 15,283 Vietnam War-era military veterans. In two Australian samples there were significant negative associations between reproductive fitness and personality measures of solid citizenship. Similarly, in the US study honourably discharged servicemen on average fathered significantly fewer children than non-honourably discharged servicemen. Since personality is genetically influenced, our results suggest that genetic variants for solid citizenship may be decreasing in frequency in some populations, in line with other modern findings but in contrast to historical analyses. Causes for this change may include relatively more conscientious women using contraception to prioritise their careers over reproduction and the availability of systematic welfare provisioning.     

Informative sources of math‐related self‐efficacy expectations and their relationship with math‐related self‐efficacy,interest, and preference

In this study, by using the hypotheses of social‐cognitive career theory (SCCT), the relationship between informative sources of math‐related self‐efficacy expectations and self‐efficacy, interest, and math‐weighted major preferences were investigated. The participants in this study were students (N = 590) from high schools in Southern Turkey. Participants completed measures of sources of math‐related self‐efficacy, self‐efficacy, interest, and choice consideration related to math‐weighted majors. While running analyses, sampling was split in half at random and psychometric analyses of the scales were run with the first half (n = 298); the second half (n = 292) was used to test the hypotheses. By doing this, the testing of hypotheses would not be affected by just one specific sampling characteristic. A structural equation model was tested and findings indicated general support for hypotheses that these sources predict self‐efficacy beliefs and these beliefs also predict interest. However, contrary to SCCT's predictions, math‐weighted major preferences are not predicted by math‐related self‐efficacy expectations and interest. In the Discussion, first, the reasons why the measurement of vicarious learning or modelling did not significantly predict self‐efficacy expectations focus on the relationships between personal accomplishments and persuasion and reported physiological arousal and personal accomplishments. Some information is given as to how counsellors and math teachers can work collaboratively to raise perceptions about informative sources. Second, explanations are given about why self‐efficacy and interest did not predict math‐weighted preferences. It is mentioned that this could be the reason for the constrained and complex system of the university entrance exams and placement in Turkey. The importance of investigating environmental variables on SCCT in developing countries was emphasized. Suggestions are also given for further research. It is concluded that this theory should be tested in developing countries like Turkey.     

Personality variables related to shyness

Shyness has been a very common Finnish characteristic as social skills are manifest. Shy people may have a good empathetic listening but self-disclosure, another aspect of empathetic communication, is missing. Shyness refers to poor social skills more than a personality trait, which would have a more genetic background, as Finns have been genetically isolated for a long time. Shy persons show a mediocre empathy (good empathetic listening and sensitivity but poor self-disclosure), weak self-esteem, weak narcissism, and sometimes more burnout.     

Mindfulness and integrative self‐knowledge: Relationships with health‐related variables

This study examined how mindfulness and integrative self‐knowledge were related to health‐related issues. Men in general population (n = 103) and coronary heart disease samples (n = 101) completed the Mindful Attention Awareness Scale, the Integrative Self‐knowledge Scale, the Type 2 subscale of the Interpersonal Reactions Inventory, the Perceived Stress Scale, and the Anxiety and Depression Scales. In both samples, there was a moderate positive correlation between mindfulness and integrative self‐knowledge and they were negatively correlated with all health‐related variables. However, only integrative self‐knowledge explained independent variance in health‐related variables. Specifically, in both samples, the relationship between mindfulness and health‐related variables was mediated by integrative self‐knowledge. Mindfulness and integrative self‐knowledge are related domains of self‐awareness that are associated with a range of health‐related variables. These relationships are robust across samples drawn from general population and patients with coronary heart disease. The finding that integrative self‐knowledge explained additional variance in the health‐related variables after the contribution of mindfulness had been accounted for suggests that reflective self‐awareness in integrative self‐knowledge may make a unique contribution to the explanation of individual differences in health variables.     

Six‐Month Trajectory of Suicidal Ideation in Adolescents with Borderline Personality Disorder

Few studies have longitudinally examined suicidal ideation in those with adolescent‐onset borderline personality disorder (BPD). The current study aimed to examine the trajectory of suicidal ideation in adolescents with BPD longitudinally over 6 months, with follow‐ups at 2, 4, and 6 months posthospitalization for elevated suicide risk. Results indicated that the BPD group exhibited a greater decrease in suicidal ideation in the months following hospitalization than those without a BPD diagnosis. The findings of this study indicated that suicidal ideation in adolescents with BPD is not stable, and although ideation may decrease quickly after hospitalization, regular assessment of ideation is recommended.     

Influence of Proactive Personality on Career Self‐Efficacy

This study examined the relationship between proactive personality and career decision‐making self‐efficacy. In Study 1, the authors validated the Proactive Personality Scale–Korean Short Form, using the Rasch model with 315 participants, and found that fit statistics, point‐measure correlations, and item difficulty estimates satisfy the construct validity criterion. In Study 2, the authors administered the Proactive Personality Scale, Career Decision‐Making Self‐Efficacy Scale, and Career Search Self‐Efficacy Scale to 296 freshman and sophomore college students. Hierarchical regression analyses showed that proactive personality scores explain additional variance in both career decision‐making self‐efficacy and career search self‐efficacy scores. Implications for theory and practice are discussed.     

Regional Analysis of Self‐Reported Personality Disorder Criteria

ABSTRACT Building on the theoretical work of Louis Guttman, we propose that the core problem facing research into the multidimensional structure of the personality disorders is not the identification of factorial simple structure but rather detailed characterization of the multivariate configuration of the diagnostic criteria. Dimensions rotated to orthogonal or oblique simple structure are but one way out of many to characterize a multivariate map, and their current near universal application represents a choice for a very particular set of interpretive advantages and disadvantages. We use multidimensional scaling and regional interpretation to investigate the structure of 78 self‐reported personality disorder criteria from a large sample of military recruits and college students. Results suggest that the criteria have a three‐dimensional radex structure that conforms only loosely to the 10 existing personality disorder (PD) categories. Regional interpretation in three dimensions elucidates several important aspects of PDs and their interrelationships.     

Age‐related changes in the dynamics of fear‐related regulation in early childhood

Self‐regulation is a dynamic process wherein executive processes (EP) delay, minimize or desist prepotent responses (PR) that arise in situations that threaten well‐being. It is generally assumed that, over the course of early childhood, children expand and more effectively deploy their repertoire of EP‐related strategies to regulate PR. However, longitudinal tests of these assumptions are scarce in part because self‐regulation has been mostly studied as a static construct. This study engages dynamic systems modeling to examine developmental changes in self‐regulation between ages 2 and 5 years. Second‐by‐second time‐series data derived from behavioral observations of 112 children (63 boys) faced with novel laboratory‐based situations designed to elicit wariness, hesitation, and fear were modeled using differential equation models designed to capture age‐related changes in the intrinsic dynamics and bidirectional coupling of PR (fear/wariness) and EP (strategy use). Results revealed that dynamic models allow for the conceptualization and measurement of fear regulation as intrinsic processes as well as direct and indirect coupling between PR and EP. Several patterns of age‐related changes were in line with developmental theory suggesting that PR weakened and was regulated more quickly and efficiently by EP at age 5 than at age 2. However, most findings were in the intrinsic dynamics and moderating influences between PR and EP rather than direct influences. The findings illustrate the precision with which specific aspects of self‐regulation can be articulated using dynamic systems models, and how such models can be used to describe the development of self‐regulation in nuanced and theoretically meaningful ways.     

Personality variables and metabolic control in children with diabetes

Insulin-dependent diabetic children and a group of their nondiabetic peers were compared on measures of self-concept, locus of control and health locus of control. A metabolic measure of long term diabetes control was also obtained on the children with diabetes. Data analyses revealed that metabolic control was not related to any of the personality measures in the diabetic sample. Diabetic and non-diabetic children did not differ on measures of locus of control and self-concept, but diabetics exhibited a health locus of control which was significantly more internal than that of control subjects. A possible explanation for these results was discussed and practical implications for health care providers working with young diabetics were presented.