The personality theories of H.J. Eysenck and J.A. Gray: a comparative review

Dispositional factors in the explanation of symptoms of depression, anxiety, health anxiety and COVID-19 Phobia

Maladaptive personality, the motivational systems, and intolerance of uncertainty play important roles in the statistical explanation of depression and anxiety. Here, we notably examined for the first time whether symptoms of depression, anxiety, health anxiety, and fear of COVID-19 share similar associations (e.g., variance explained) with these important dispositional dimensions. For this cross-sectional study, data from 1001 participants recruited in Germany (50% women; mean age = 47.26) were collected. In separate models, we examined the cross-sectional associations of the symptoms of depression, anxiety, health anxiety, and fear of COVID-19 with the Personality Inventory for DSM Short Form Plus scales, the Behavioral Inhibition System / Flight-Fight-Freeze System / Behavioral Activation System scales, and Intolerance of Uncertainty scales. Relative weight analyses were used to determine the within-model importance of the different scales in the prediction of the symptoms. All in all, our study showed that maladaptive personality and intolerance of uncertainty dimensions are more important sets of predictors of the studied outcomes (with which depressive and anxious symptomatology feature very similar associations) than are the motivational system dimensions. Within predictor sets, the scales with the most important predictors were: Negative Affectivity, the Behavioral Inhibition System, and Burden due to Intolerance of Uncertainty. Our findings highlight the relevance of focusing behavioral targets of psychotherapy on these within-set traits and identify potential research priorities (maladaptive personality and intolerance of uncertainty) in relation to the symptoms of interest.

How is variability in physiological responses to social stress related to punishment and reward sensitivities? Preliminary findings from the revised reinforcement sensitivity theory of personality perspective

OBJECTIVE

Although personality traits are assumed to have biological/physiological foundations, research has yielded mixed evidence regarding the relationship between personality and physiological stress responses. Moreover, the field has often overlooked the contemporary neuroscience-based personality approach, known as the Reinforcement Sensitivity Theory (RST) of Personality, in stress research.

METHOD

The present study examined the relationship between the revised RST's personality dimensions and heart rate and skin conductance level (SCL) in response to the Trier Social Stress Test in a sample of 61 healthy university students.

RESULTS

Piecewise latent growth curve analysis controlling for the participants' current life stress, smoking use, and caffeine intake revealed that individuals with higher behavioral inhibition exhibited higher physiological reactivity, whereas those with high reward sensitivity showed smaller heart rate reactivity. The behavioral disengagement facet of the behavioral inhibition scale was associated with reduced sympathetic arousal during the stress task. Additionally, reward interest was associated with a larger recovery of SCL.

CONCLUSION

Results were generally in line with the revised theory. The study findings were discussed within the paradigm of the approach-avoidance conflict and highlighted the importance of reward sensitivity in stress resilience.

Emotional urgency predicts bipolar symptoms, severity, and suicide attempt better than non-emotional impulsivity: a cross-sectional study

Introduction

Emotional urgency is an emotion-based subdimension of trait impulsivity that is more clinically relevant to psychopathology and disorders of emotion dysfunction than non-emotional subdimensions (i.e., lack of perseverance, sensation seeking, lack of premeditation). However, few studies have examined the relative effects of emotional urgency in bipolar disorder. This cross-sectional study aimed to establish the clinical relevance of emotional urgency in bipolar disorders by (1) explicating clinically relevant correlates of emotional urgency and (2) comparing its effects against non-emotional impulsivity subdimensions.

Methods and results

A total of 150 individuals with bipolar disorder were recruited between October 2021 and January 2023. Zero-order correlations found that emotional urgency had the greatest effect on bipolar symptoms (r = 0.37 to 0.44). Multiple two-step hierarchical regression models showed that (1) positive urgency predicted past manic symptomology and dysfunction severity (b = 1.94, p < 0.001 and 0.35 p < 0.05, respectively), (2) negative urgency predicted current depression severity, and (3) non-emotional facets of impulsivity had smaller effects on bipolar symptoms and dysfunction by contrast, and were non-significant factors in the final step of all regression models (b < 0.30, ns); Those who had a history of attempted suicide had significantly greater levels of emotional urgency (Cohen's d = -0.63).

Discussion

Notwithstanding the study's limitations, our findings expand status quo knowledge beyond the perennial relationship between non-emotion-based impulsivity and bipolar disorder and its implications.

Emotion, motivation, decision-making, the orbitofrontal cortex, anterior cingulate cortex, and the amygdala

The orbitofrontal cortex and amygdala are involved in emotion and in motivation, but the relationship between these functions performed by these brain structures is not clear. To address this, a unified theory of emotion and motivation is described in which motivational states are states in which instrumental goal-directed actions are performed to obtain rewards or avoid punishers, and emotional states are states that are elicited when the reward or punisher is or is not received. This greatly simplifies our understanding of emotion and motivation, for the same set of genes and associated brain systems can define the primary or unlearned rewards and punishers such as sweet taste or pain. Recent evidence on the connectivity of human brain systems involved in emotion and motivation indicates that the orbitofrontal cortex is involved in reward value and experienced emotion with outputs to cortical regions including those involved in language, and is a key brain region involved in depression and the associated changes in motivation. The amygdala has weak effective connectivity back to the cortex in humans, and is implicated in brainstem-mediated responses to stimuli such as freezing and autonomic activity, rather than in declarative emotion. The anterior cingulate cortex is involved in learning actions to obtain rewards, and with the orbitofrontal cortex and ventromedial prefrontal cortex in providing the goals for navigation and in reward-related effects on memory consolidation mediated partly via the cholinergic system.

Reinforcement sensitivity theory may predict COVID-19 infection outcome and vulnerability

Research suggests that specific behavior patterns may be related with the outcome and vulnerability of a COVID-19 infection; nevertheless, much of this information has been obtained by means of psychological paradigms that are not based on research conducted using experimental designs. Thus, the purpose of the present study was to identify behavior patterns associated with COVID-19 outcome and vulnerability from the point of view of the Reinforcement Sensitivity Theory. A total of 464 college students from Mexico-City participated in the study. Participants answered the Behavior Inhibition, Behavior Activation scales (Carver & White, 1994), the Reinforcement Sensitivity Theory Personality Questionnaire (Corr & Cooper, 2016) and a COVID-19 symptom checklist. Data showed that those individuals who respond in an enthusiastic way to rewards develop less symptoms of COVID-19. Additionally, individuals who are keen in the exploration and identification of new rewarding opportunities are less likely to develop a COVID-19 infection. Both findings suggest that a potent Behavior Activation System could protect individuals during the present pandemic. These results are in general agreement with others produced within the same framework.

Social support at work and job satisfaction among midwives: The mediating role of positive affect and work engagement

AIMS

This study examined whether social support at work from superiors and colleagues is associated with positive affect at work, and whether work engagement creates a positive relationship with job satisfaction among midwives. We also investigated whether a positive affect and work engagement mediate the relationship between social support at work and job satisfaction.

DESIGN

This was a quantitative cross-sectional study.

METHODS

Data were collected from 163 midwives working in the Polish public healthcare system between June 2019 and December 2019.

RESULTS

There was a direct relationship between support from superiors and colleagues, positive affect at work, work engagement and job satisfaction. The relationship between support from superiors and job satisfaction was mediated partially by positive affect at work and work engagement. In contrast, the relationship between support from colleagues and job satisfaction was mediated entirely by positive affect at work and work engagement.

CONCLUSION

Support from colleagues, compared to support from superiors, was a stronger predictor of positive affect at work and job satisfaction among midwives. Support at work is a resource that leads to higher job satisfaction by generating positive feelings and increasing work engagement.

IMPACT

We recommend paying particular attention to the role of inter-personal relationships and positive feelings at work in shaping the level of satisfaction with work among midwives. The personnel management policy at healthcare institutions should be oriented towards strengthening supportive attitudes in the workplace.

Two Measures of Interoceptive Sensibility and the Relationship With Introversion and Neuroticism in an Adult Population

Interoception, the ability to detect internal bodily signals, is vital for an individual's well-being and is increasingly connected to mental health disorders. Research investigating relationships between individual differences in interoception and personality types is limited, and mixed results are reported across a variety of interoceptive tasks, measures, and conceptualisations. Guided by biological theories, this study contributed further to the understanding of the relationship between interoception and personality by utilising two interoceptive measures. A sample of adults (N = 114) completed three questionnaires online questionnaire, two assessing interoceptive sensibility (Body Perception Questionnaire, BPQ; and the Multidimensional Assessment of Interoceptive Awareness, MAIA) and one that assessed personality (Eysenck Personality Inventory, EPI). Multiple regression and correlational analyses showed no significant relationship between interoceptive sensibility and introversion, whereas a predictive relationship was demonstrated between interoceptive sensibility and neuroticism. Furthermore, the BPQ and subscales of the MAIA predicted neuroticism in different directions suggesting the two measures assess different constructs and thus strengthened support for a multidimensional consideration of interoception. The results have clinical implications, including the targeting of contemplative training approaches for individuals demonstrating high interoceptive sensibility and neurotic traits to improve the mental well-being of healthy individuals and clinical populations.

Relationships Among Personality, Daily Speaking Voice Use, and Phonotrauma in Adult Female Singers

PURPOSE

This study sought to determine whether personality traits related to extraversion and impulsivity are more strongly associated with singers with nodules compared to vocally healthy singers and to understand the relationship between personality and the types of daily speaking voice use.

METHOD

Weeklong ambulatory voice recordings and personality inventories were obtained for 47 female singers with nodules and 47 vocally healthy female singers. Paired t tests investigated trait differences between groups. Relationships between traits and weeklong speaking voice measures (vocal dose, sound pressure level [SPL], neck surface acceleration magnitude [NSAM], fundamental frequency, cepstral peak prominence [CPP], and the ratio of the first two harmonic magnitudes [H 1 -H 2]) were examined using pairwise Pearson r coefficients. Multiple regressions were performed to estimate voice parameters that correlated with two or more traits.

RESULTS

Singers with nodules scored higher on the Social Potency scale (reflecting a tendency toward social dominance) and lower on the Control scale (reflecting impulsivity) compared to the vocally healthy singers. In vocally healthy singers, vocal dose measures were positively correlated with a combination of Wellbeing (i.e., happiness) and Social Potency, mean SPL was positively correlated with Wellbeing, SPL variability was positively correlated with Social Potency and negatively with Harm Avoidance, and CPP mean was positively correlated with Wellbeing. Singers with nodules had a negative correlation between NSAM skewness and Social Potency. Both groups had negative correlations between H 1 -H 2 mean and Social Potency and Social Closeness.

CONCLUSIONS

Singers with nodules are more socially dominant and impulsive than vocally healthy singers. Personality traits are related to daily speaking voice use, particularly in vocally healthy singers. Individuals with higher levels of traits related to happiness and social dominance and lower Harm Avoidance tended to speak more, with higher laryngeal forces, with more SPL variability, and with more pressed glottal closure, which could increase risk of phonotrauma.

The Big Five Personality Traits and Brain Arousal in the Resting State

Based on Eysenck's biopsychological trait theory, brain arousal has long been considered to explain individual differences in human personality. Yet, results from empirical studies remained inconclusive. However, most published results have been derived from small samples and, despite inherent limitations, EEG alpha power has usually served as an exclusive indicator for brain arousal. To overcome these problems, we here selected N = 468 individuals of the LIFE-Adult cohort and investigated the associations between the Big Five personality traits and brain arousal by using the validated EEG- and EOG-based analysis tool VIGALL. Our analyses revealed that participants who reported higher levels of extraversion and openness to experience, respectively, exhibited lower levels of brain arousal in the resting state. Bayesian and frequentist analysis results were especially convincing for openness to experience. Among the lower-order personality traits, we obtained the strongest evidence for neuroticism facet 'impulsivity' and reduced brain arousal. In line with this, both impulsivity and openness have previously been conceptualized as aspects of extraversion. We regard our findings as well in line with the postulations of Eysenck and consistent with the recently proposed 'arousal regulation model'. Our results also agree with meta-analytically derived effect sizes in the field of individual differences research, highlighting the need for large (collaborative) studies.

The Big Five Personality Traits and Brain Arousal in the Resting State

Based on Eysenck's biopsychological trait theory, brain arousal has long been considered to explain individual differences in human personality. Yet, results from empirical studies remained inconclusive. However, most published results have been derived from small samples and, despite inherent limitations, EEG alpha power has usually served as an exclusive indicator for brain arousal. To overcome these problems, we here selected N = 468 individuals of the LIFE-Adult cohort and investigated the associations between the Big Five personality traits and brain arousal by using the validated EEG- and EOG-based analysis tool VIGALL. Our analyses revealed that participants who reported higher levels of extraversion and openness to experience, respectively, exhibited lower levels of brain arousal in the resting state. Bayesian and frequentist analysis results were especially convincing for openness to experience. Among the lower-order personality traits, we obtained the strongest evidence for neuroticism facet 'impulsivity' and reduced brain arousal. In line with this, both impulsivity and openness have previously been conceptualized as aspects of extraversion. We regard our findings as well in line with the postulations of Eysenck and consistent with the recently proposed 'arousal regulation model'. Our results also agree with meta-analytically derived effect sizes in the field of individual differences research, highlighting the need for large (collaborative) studies.

Personality predictors of creative achievement and lawbreaking behavior

This article investigates how Big Five personality traits are related to creative achievements and lawbreaking behavior in a large sample (N = 1669) of Polish adults. Structural equation modelling with personality modelled as a bi-factor structure demonstrated a weak, yet significant link (r = .21) between latent factors of creative achievements and lawbreaking behavior. A general factor of personality was unrelated to creative achievement, but negatively linked to lawbreaking behavior. Lawbreaking behavior was also negatively predicted by conscientiousness and agreeableness, while only openness positively predicted creative achievement. A person-centered analysis illustrated three distinct personality profiles: resilient, undercontrolled, and overcontrolled that differed in both lawbreaking behavior and creative achievements.

The structural characteristics and influential factors of psychological stress of urban residents in Jiangxi province during the COVID-19 pandemic: cross sectional study

AIMS

To explore the structural characteristics and influential factors of psychological stress of urban residents in Jiangxi province during the COVID-19 pandemic through a survey of psychological stress, personality traits, family function and life satisfaction.

METHODS

By the convenient sampling, 1422 urban residents from Jiangxi province were assessed with Eysenck Personality Questionnaire Short Scale (EPQ-RSC), Psychological Questionnaires for Emergent Events of Public Health (PQEEPH), Family APGAR Scale (APGAR) and Satisfaction With Life Scale (SWLS). The relation among personality traits, psychological stress, family function and life satisfaction during the COVID-19 pandemic was analyzed by using the canonical correlation analysis and the serial mediation model.

RESULTS

(1) Among the estimated correlation coefficients, the first two pairs were significant (P < 0.001 in each). (2) In the first pair of canonical variables, the loadings of neuroticism and neurasthenia were the higher (0.94, 0.70). (3) Neuroticism and life satisfaction mediated the relationship between family function and neurasthenia (β neuroticism = -0.174; 95%CI:-0.224, -0.134; β life satisfaction = -0.034, 95%CI:-0.012, -0.062), respectively. In addition, serial mediation analyses indicated that the association of family function and neurasthenia is mediated by neuroticism and life satisfaction in a sequential manner (β = -0.010; 95%CI:-0.020, -0.004).

CONCLUSIONS

During the COVID-19 pandemic, neuroticism was closely related to psychological stress of urban residents, especially neurasthenia. In addition, the serial mediating effect of neuroticism and life satisfaction played an important role in the process of family function influencing neurasthenia. These findings contributed to a more comprehensive understanding of the influential factors for psychological stress of urban residents during the COVID-19 pandemic.

Comparison of personality profile of prison criminals in the Yasooj Central Penitentiary and noncriminals based on 16 personality factors

AIMS

The study was conducted to examine the personality profile of prisoners in the Yasooj Central Penitentiary (YCP) according to Cattell's 16 Personality Factors (PFs) Model.

SETTINGS AND DESIGN

In doing so, 50 prisoners were selected from among all 20-35-year-old male prisoners at YCP. Moreover, 50 people were selected from the nonprison community to match with the prisoner group.

SUBJECTS AND METHODS

In a causal-comparative study, both groups were matched and were evaluated using two questionnaires: demographic information and Cattell's 16-PF questionnaires.

STATISTICAL ANALYSIS USED

The statistical method used to predict the distinguishing personality traits of the two groups, prisoners and nonprisoners, was discriminant analysis.

RESULTS

The results indicated that from among Cattell's 16 factors, only 7 factors in the two groups were discriminant and predicting crime: Conservative, sober, expedient, self-control, imaginative, reserved, and tough mindedness.

CONCLUSIONS

According to the results, 16 main factors of personality have the ability to predict crime.

Big Five traits as predictors of perceived stressfulness of the COVID-19 pandemic

This study examined the Big Five personality traits as predictors of individual differences and changes in the perceived stressfulness of the COVID-19 pandemic in Germany between early April 2020 and early September 2020. This timeframe includes the first national “lockdown,” the period of “easing” of restrictions, and the summer vacation period. Data were collected from n = 588 full-time employees, who provided baseline data on their personality traits in early December 2019, and then later provided data on perceived stressfulness of the COVID-19 pandemic at five time points, spanning six months. Consistent with expectations based on event and transition theories, results showed that, on average, perceived stressfulness declined between early April 2020 and early September 2020. Moreover, this effect was stronger between early April 2020 and early July 2020. Hypotheses based on the differential reactivity model of personality and stress were partially supported. Emotional stability was associated with lower, and extraversion associated with higher, average levels of perceived stressfulness. Finally, extraversion was associated with increases (i.e., positive trajectories) in perceived stressfulness between early April 2020 and early July 2020 and decreases (i.e., negative trajectories) in perceived stressfulness between early July 2020 and early September 2020.

The search for causality of personality-chronotype associations: insights from a one-year longitudinal study of adolescents

Associations between certain personality traits and individual differences in diurnal preferences, referred to as morningness-eveningness, are well established from cross-sectional studies. However, it is unclear whether personality affects diurnal preference, diurnal preference affects personality, or some third factor influences both. The current study assessed the Big Five personality traits and morningness-eveningness in a one-year, two-wave longitudinal design, in a sample of 169 Polish high school students (59% females), aged 16-17 years (M = 16.80, SD = 0.39) during the first wave of measurement. During the second wave the participants were respectively 1 year older. Cross lagged panel analyses were run to determine wave 1 predictors of wave 2 variables. Cross-sectional analyses replicated the association between morningness and conscientiousness that has been reliably found in previous studies, but the cross-lagged paths between these variables were nonsignificant. These two traits appear to be intrinsically linked to one another by adolescence, possibly as a consequence of genetic influences that shape temperament earlier in childhood. In contrast, emotional stability and morningness were not significantly correlated in wave 1 cross-sectional data, but a significant relationship was found in the cross-lagged panel analysis. Wave 1 emotional stability predicted wave 2 morningness, although wave 1 morningness did not predict personality. We tentatively suggest that there may be a causal effect of personality on diurnal preference, associated with avoidance strategies for coping with academic stress as the high school years approach their end. More neurotic individuals may cope with their aversion to classes by distracting themselves with evening pursuits, such as use of the internet. Further work might examine in more depth how contextual stressors interact with personality to affect daily activities at different times of the day.

What is reinforcement sensitivity? Neuroscience paradigms for approach‐avoidance process theories of personality

Reinforcement sensitivity is a concept proposed by Gray (1973) to describe the biological antecedents of personality, and has become the common mechanism among a family of personality theories concerning approach and avoidance processes. These theories suggest that 2–3 biobehavioural systems mediate the effects of reward and punishment on emotion and motivation, and that individual differences in the functioning of these systems manifest as personality. Identifying paradigms for operationalising reinforcement sensitivity is therefore critical for testing and developing these theories, and evaluating their footprint in personality space. In this paper I suggest that, while traditional self‐report paradigms in personality psychology may be less‐than‐ideal for this purpose, neuroscience paradigms may offer operations of reinforcement sensitivity at multiple levels of approach and avoidance processes. After brief reflection on the use of such methods in animal models—which first spawned the concept of reinforcement sensitivity—recent developments in four domains of neuroscience are reviewed. These are psychogenomics, psychopharmacology, neuroimaging and category‐learning. By exploring these paradigms as potential operations of reinforcement sensitivity we may enrich our understanding of the putative biobehavioural bases of personality. Copyright © 2008 John Wiley & Sons, Ltd.

Gray's model of personality and aggregate level factor analysis

Previous research shows that correlations tend to increase in magnitude when individuals are aggregated across groups. This suggests that uncorrelated constellations of personality variables (such as the primary scales of Extraversion and Neuroticism) may display much higher correlations in aggregate factor analysis. We hypothesize and report that individual level factor analysis can be explained in terms of Giant Three (or Big Five) descriptions of personality, whereas aggregate level factor analysis can be explained in terms of Gray's physiological based model. Although alternative interpretations exist, aggregate level factor analysis may correctly identify the basis of an individual's personality as a result of better reliability of measures due to aggregation. We discuss the implications of this form of analysis in terms of construct validity, personality theory, and its applicability in general. Copyright © 2003 John Wiley & Sons, Ltd.

Evolution, genes, and inter‐disciplinary personality research

Most commentaries welcomed an evolutionary genetic approach to personality, but several raised concerns about our integrative model. In response, we clarify the scientific status of evolutionary genetic theory and explain the plausibility and value of our evolutionary genetic model of personality, despite some shortcomings with the currently available theories and data. We also have a closer look at mate choice for personality traits, point to promising ways to assess evolutionarily relevant environmental factors and defend higher‐order personality domains and the g‐factor as the best units for evolutionary genetic analyses. Finally, we discuss which extensions of and alternatives to our model appear most fruitful, and end with a call for more inter‐disciplinary personality research grounded in evolutionary theory. Copyright © 2007 John Wiley & Sons, Ltd.

Extraversion and Neuroticism as antecedents of emotion regulation and dysregulation in adulthood

This longitudinal study examined the role of Extraversion and Neuroticism as antecedents of emotion regulation and dysregulation among 89 women and 81 men. When participants were 27 years old, their Extraversion and Neuroticism were assessed with the standardized version of the Eysenck Personality Questionnaire. At age 33, they completed the Big‐Five Personality Inventory, an authorized adaptation of the NEO Personality Inventory. Emotion regulation, operationalized as an active attempt to turn a negative emotion toward a more positive direction, and measured by the Repair subscale of the Meta‐Regulation Scale, and emotional social support, as measured by the Life Situation Questionnaire, were assessed when participants reached 36 years of age. Emotional ambivalence, a type of emotion dysregulation, was also assessed in this wave. Structural equation modelling demonstrated that prior Neuroticism led to higher emotional ambivalence and lowered use of Repair at age 36. Prior Extraversion, on the other hand, was linked to lower emotional ambivalence at age 36. Extraversion also led to higher attempts to rely on emotional social support to regulate emotions, but less interest in using Repair. Correlational findings revealed that Extraversion and Neuroticism showed differential continuity between ages 27 and 33. Copyright © 2001 John Wiley & Sons, Ltd.

The conceptualisation, measurement and scope of reinforcement sensitivity in the context of a neuroscience of personality

Reinforcement sensitivity theory (RST) is complex, and there are subtle differences between RST and other approach‐avoidance process theories of personality. However, most such theories posit a common biobehavioural mechanism underlying personality which we must therefore strive to understand: differential sensitivity to reinforcing stimuli. Reinforcement sensitivity is widely assessed using questionnaires, but should we treat such measures as (a) a proxy for reinforcement sensitivity itself (i.e. the underlying causes of personality) or (b) trait constructs potentially manifesting out of reinforcement sensitivity (i.e. the ‘surface’ of personality)? Might neuroscience paradigms, such as those I have reviewed in my target paper, provide an advantage over questionnaires in allowing us to move closer to (a), thereby improving both the measurement and our understanding of reinforcement sensitivity? Assuming we can achieve this, how useful is reinforcement sensitivity—and biological perspectives more generally—for explaining personality? These are the major questions raised in the discussion of my target paper, and among the most pertinent issues in this field today. Copyright © 2008 John Wiley & Sons, Ltd.

Trait BIS predicts alpha asymmetry and P300 in a Go/No‐Go task

Inspired by the revised Behavioural Inhibition System (BIS) theory the present study probed the association between individual differences in Trait BIS and electroencephalogram indicators of conflict processing/inhibition. Sixty‐nine male participants either high or low in Trait BIS completed a Go/No‐Go task while the electroencephalogram was recorded. As expected, Trait BIS was associated with the No‐Go‐anteriorisation of the P300 event‐related potential (i.e. an index of response inhibition presumably generated in the dorsal anterior cingulate—an area implicated in conflict processing) and with No‐ Go‐related changes towards left frontal alpha activity (i.e. presumably more activity in right prefrontal cortex—an area implicated in response inhibition). These findings support the role of conflict processing attributed to BIS functioning in the revised theory. Copyright © 2009 John Wiley & Sons, Ltd.

Personality variable differences between disease clusters

Previous studies of personality and health have focused mainly on the influence of psychological factors on single diseases such as cancer and coronary heart disease (CHD), thereby neglecting the problem of comorbidity (i.e. the combination of different diseases). The main focus of the present study was the discrimination between single‐ and multiple‐disease conditions on the basis of personality traits. An extensive battery of personality scales implicated in health was administered to a sample of n=5133 individuals of both genders between the ages of 40 and 65. Subjects also reported their health or illness status. A factor analysis of the personality scales yielded five dimensions clearly interpretable as “Emotional Lability”, “Type A Behaviour”, “Behavioural Control”, “Locus of Control over Diseases”, and “Psychoticism”. Hierarchical cluster analyses of the subsample of participants who reported suffering from more than one disease led to eight clusters representing individuals with different combinations of diseases. Generally, there were very few significant differences between healthy and single‐disease participants with regard to personality. However, mean factor scores calculated for “Emotional Lability” were higher across the multiple‐disease groups than in the healthy and single‐disease groups. No other personality factor showed this trend. In general the results reported here show the important role negative affectivity (e.g. Emotional Lability, Neuroticism, Depression) plays in differentiating between single and multiple diseases. Copyright © 2003 John Wiley & Sons, Ltd.

From BIS/BAS to the big five

Gray (1987) proposed two systems that underlie much of our behaviour and personality. One system relates to avoidance or withdrawal behaviour, called the Behavioural Inhibition System (BIS), whereas the other system relates to approach behaviour, called the Behavioural Approach System (BAS). In two samples, it was investigated whether individual differences in surface of personality as described by the Big Five can be explained by BIS/BAS. Neuroticism and Extraversion could be explained well by BIS/BAS, but also for Agreeableness and Conscientiousness consistent findings were obtained. Copyright © 2006 John Wiley & Sons, Ltd.

The assessment of behavioural activation—the relationship between positive emotionality and the behavioural activation system

Much personality research suggests that the variance in personality can be accounted for by a few dimensions, often hypothesized to be connected to neurological circuits. Gray's (1982) behavioural activation system (BAS) and behavioural inhibition system (BIS) in particular propose to explain for a variety of behaviour. This investigation sought to determine whether Positive Emotionality is an appropriate measure of the BAS, and how Tellegen's (1985) constructs are related to BAS activity. Measures of BAS and Positive Emotionality were administered to undergraduates. Confirmatory factor analyses revealed that, while Positive Emotionality can be used as an indicator of BAS activity, it is better conceived of as a distinct, correlated construct. In addition, not all components of Positive Emotionality were related to BAS activity, and BAS was further related to components of Negative Emotionality and Constraint. Copyright © 2004 John Wiley & Sons, Ltd.

Relationship Between Trait Mindfulness and Sleep Quality in College Students: A Conditional Process Model

Sleep quality can affect the physical and mental health, as well as the personal development of college students. Mindfulness practices are known to ameliorate sleep disorder and improve sleep quality. Trait mindfulness, an innate capacity often enhanced by mindfulness training, has been shown to relate to better sleep quality and different aspects of psychological well-being. However, how individual difference factors such as trait mindfulness relate to sleep quality remains largely unclear, which limits the optimization and further application of mindfulness-based intervention schemes targeting the improvement of sleep quality. In this study, we aimed to investigate how negative emotions and neuroticism may influence the relationship between trait mindfulness and sleep quality. A conditional process model was built to examine these relationships in 1,423 Chinese young adults. Specifically, the conditional process model was constructed with trait mindfulness as the independent variable, sleep quality as the dependent variable, negative emotions as the mediating variable, and neuroticism as the moderating variable. Our results showed that negative emotions mediated the link between mindfulness and sleep quality and that neuroticism had a moderating effect on the relationship between mindfulness and sleep quality. Together, these findings suggested a potential mechanism of how trait mindfulness influences sleep quality, provided a therapeutic target for which mindfulness-based interventions may act upon to improve sleep quality, and offered a basis for prediction of different intervention effects among individuals.

Hypersexual Behaviors and Personality Traits in Men with Substance Use Disorders in Iran

The present study was conducted aiming to compare the five-factor model of personality in addicted men with and without hypersexual disorder (HD). The research method was causal-comparative, and the study population included all addicted men who were residents of addiction treatment centers in Tabriz city. 216 male addicts with HD and without HD were compared in 2 groups of 108 members through the Big Five Inventory (BFI-44). Data were analyzed using independent t test, chi-square, multivariate analysis of variance, and SPSS 22 version software for Windows (IBM Corporation, Armonk, NY, USA). The results showed that 2 groups were significantly different in the five-factor model of personality. Addicted men with HD obtained lower scores in agreeableness, conscientiousness, and openness to experience; and obtained higher scores in neuroticism personality dimension in comparison to addicted men without HD. There was no significant difference between the 2 groups in extraversion dimension. These findings indicated that there is a significant difference between the 2 groups in the five-factor model of personality, and addicted men with HD scored higher in neuroticism dimension. Therefore, this study illustrates the need to pay attention to the personality dimension of neuroticism (or emotional instability) as a variable comorbid with HD and substance-related disorders.

Cognitive Processes Unfold in a Social Context: A Review and Extension of Social Baseline Theory

Psychologists often assume that social and cognitive processes operate independently, an assumption that prompts research into how social context influences cognitive processes. We propose that social and cognitive processes are not necessarily separate, and that social context is innate to resource dependent cognitive processes. We review the research supporting social baseline theory, which argues that our default state in physiological, cognitive, and neural processing is to incorporate the relative costs and benefits of acting in our social environment. The review extends social baseline theory by applying social baseline theory to basic cognitive processes such as vision, memory, and attention, incorporating individual differences into the theory, reviewing environmental influences on social baselines, and exploring the dynamic effects of social interactions. The theoretical and methodological implications of social baseline theory are discussed, and future research endeavors into social cognition should consider that cognitive processes are situated within our social environments.

Factor Structure of the Early Adolescent Temperament Questionnaire-Revised

Early adolescence (typically aged 9-15 years) is a period of dramatic developmental change, and individual differences in temperament is likely to be an important predictor of the success with which individuals negotiate this period of life. Moreover, early adolescent temperament cannot be adequately captured by measures designed for other age groups. This study examined the empirical validity of the proposed temperament factors of the Early Adolescent Temperament Questionnaire-Revised (EATQ-R) in a large representative sample of 2,453 early adolescents aged between 10 and 12 years of age, and compared it with models that include cross-loadings between items and first-order factors, as well as first- and second-order factors. Furthermore, the reproducibility of the factor structure established by using a cross validation approach. Adding cross-loadings to the EATQ-R fit the data substantially better, resulting in an overall good fit that the original EATQ-R model did not achieve. However, the conceptual interpretation of the first- and second-order factor structures were not substantially altered even with this addition of cross-loadings. Future research should establish the construct validity of the first- and second-order factors as measured by this empirically based factor structure.

Validation of a Questionnaire for Personality Profiling using Cognitive Diagnostic Modeling

This article describes the development of the ENCUIST (Extroversion, Neuroticism, Callous-Unemotional, Instability, Short-Test) questionnaire, which has been created to provide a personality profiling method based on a cognitive diagnostic modeling framework. The ENCUIST measures the attributes of extroversion, neuroticism, callous unemotionality and overt expressions of anger that are relevant in a forensic context. The scores provided by the ENCUIST are binary classifications of the individuals (high/low) in these attributes. The ENCUIST was developed using a sample of 516 subjects to study its validation through psychometric procedures, including factor analysis, cognitive diagnostic modeling and structural equation modeling. The results supported a four-factor structure. Linear regressions were used to evaluate the predictive validity of the scores provided by ENCUIST with respect to two external criteria that are relevant in the forensic context, namely behavioral activation and behavioral inhibition. The results showed that the extroversion dimension is positively related to behavioral activation, although the effect size is modest and the proportion of explained variance is only 11%. Moreover, the dimensions of neuroticism and anger expression are positively related to behavioral inhibition, with 7% of the variance explained. Together, these results suggest that cognitive diagnostic models are useful tools for the elaboration of personality profiles based on classifying subjects along binary attributes.

Social Contact and Cognitive Functioning: The Role of Personality

Objectives

Social contact has been shown to be positively associated with cognitive functioning. It is unclear, however, whether all individuals can equally benefit from social contact with regard to their cognitive functioning. The goal of this study was to examine whether the beneficial effects of social contact are affected by individual differences in personality.

Method

We examined the Big Five personality traits as moderators of the associations between social contact and episodic memory and executive functioning using the second wave of the Midlife in the U.S. study (N = 3,524, M(age) = 55.8).

Results

High levels of Extraversion and low levels of Openness to Experience strengthened the association between social contact and memory and executive functioning. High levels of Neuroticism and Agreeableness weakened the association of social contact with memory but not with executive functioning. The results are consistent across adulthood.

Discussion

Personality modifies the social contact-cognition association. Whereas extraverts may need social contact for cognitive stimulation, those who are high on Openness gain their stimulations elsewhere. The highly neurotic might experience contact as stressful and hence as less beneficial. Emotional rather than cognitive motivation might be the reason that the highly agreeable benefit less from social contact with regard to their cognitive functioning.

Extraversion and behavioural approach system in stimulus analysis and motor response initiation

In this study, we attempt to validate previous findings on extraversion-related differences in speed of sensorimotor processing and to extend them into Behavioural Approach System (BAS) subtraits within the framework of the revised Reinforcement Sensitivity Theory (rRST) of personality. Here, we assessed psychological traits of extraversion (E), four BAS facets (Goal-Drive Persistence, BAS-GDP; Reward Interest, BAS-RI; Reward Reactivity, BAS-RR; Impulsivity, BAS-I), Behavioural Inhibition System (BIS), and Fight-Flight-Freeze System (FFFS) in 51 volunteers (28 women). Stimulus-locked lateralized readiness potential (S-LRP), response-locked LRP (R-LRP), stimulus-locked and response-locked forearm electromyogram (S-EMG and R-EMG), and P3 components of the event-related potentials (ERPs), were recorded during the performance of a two-choice Go/NoGo visual letter-digit discrimination task varying in task difficulty. High extraverts, relative to introverts and individuals high relative to low on BAS-RI, were more likely to exhibit shorter S-LRP latencies and stimulus- and response-locked EMG latencies. Additionally, high BAS-I had a shorter R-RLP latency than low BAS-I participants for the difficult task. High FFFS levels were associated with longer S-LRP and S-EMG latencies, while high BIS levels had larger response accuracy. Extraverts, relative to introverts, along with those high relative to low on BAS-RR and BAS-I, exhibited smaller P3 amplitudes. The faster cortical premotor initiation, found in individuals high on extraversion, BAS-RI and low on FFFS, may account for their faster peripheral motor response initiation and execution. Smaller P3 amplitudes in extraverts and individuals high on BAS-RR and BAS-I may indicate reduced perceptual processing capacity in these individuals.

EXTRAVERSION/INTROVERSION AND AGE-RELATED DIFFERENCES IN SPEED-ACCURACY TRADEOFF

ABSTRACT Introduction: Extraversion/introversion and age differences might influence speed-accuracy tradeoff. Objective: The speed-accuracy tradeoff was investigated in extroverted and introverted female children, young adults and older adults. Method: Participants carried out an alternative version of Fitts’ task, which involved making alternate clicks with the mouse held in the dominant hand, moving as fast as possible, on two rectangular targets on a computer screen in order to make twelve attempts at six random levels of difficulty (twelve combinations of target widths and distances between targets). Each of the three groups was composed of 16 introverted and 16 extroverted subjects, based upon Brazilian versions of Eysenck’s questionnaire. Results: Elderly introverts fell short of the target more often and committed more overall errors than the elderly extroverts. Additionally, compared to their younger adult counterparts, the elderly subjects fell short of the target more often and committed more overall errors, besides taking longer to complete the task with higher levels of difficulty. Conclusion: The findings were interpreted in light of theories designed to explain the main processes underlying extroversion/introversion and age-related differences. Level of Evidence II; Lesser quality prospective study.

Taxonomies of psychological individual differences: biological perspectives on millennia-long challenges

This Editorial highlights a unique focus of this theme issue on the biological perspectives in deriving psychological taxonomies coming from neurochemistry, neuroanatomy, neurophysiology, genetics, psychiatry, developmental and comparative psychology-as contrasted to more common discussions of socio-cultural concepts (personality) and methods (lexical approach). It points out the importance of the distinction between temperament and personality for studies in human and animal differential psychophysiology, psychiatry and psycho-pharmacology, sport and animal practices during the past century. It also highlights the inability of common statistical methods to handle nonlinear, feedback, contingent, dynamical and multi-level relationships between psychophysiological systems of consistent psychological traits discussed in this theme issue.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.

Is Evaluative Conditioning Moderated by Big Five Personality Traits?

Evaluative conditioning (EC), a change in liking of a stimulus due to its paired presentation with a positive or negative stimulus, is a key concept in attitude formation. The present article examines to what extent EC effects are moderated by Big Five personality. For this purpose, 567 participants completed an EC procedure and the Big Five Inventory. People high on neuroticism and agreeableness showed stronger EC effects than people low on those personality traits. In conclusion, attitude formation via EC depends in part on Big Five personality. This novel insight has important ramifications for EC research and personality research. As to EC research, the moderation by neuroticism suggests that EC effects intensify with an increased focus on valent stimuli. As to personality research, our findings reinforce the fundamental nature of the Big Five because they are evidentially able to moderate such basic learning phenomena as EC.

Eysenck's Theory of Personality and the Role of Background Music in Cognitive Task Performance: A Mini-Review of Conflicting Findings and a New Perspective

The question of whether background music is able to enhance cognitive task performance is of interest to scholars, educators, and stakeholders in business alike. Studies have shown that background music can have beneficial, detrimental or no effects on cognitive task performance. Extraversion—and its postulated underlying cause, cortical arousal—is regarded as an important factor influencing the outcome of such studies. According to Eysenck's theory of personality, extraverts' cortical arousal at rest is lower compared to that of introverts. Scholars have thus hypothesized that extraverts should benefit from background music in cognitive tasks, whereas introverts' performance should decline with music in the background. Reviewing studies that have considered extraversion as a mediator of the effect of background music on cognitive task performance, it is demonstrated that there is as much evidence in favor as there is against Eysenck's theory of personality. Further, revisiting Eysenck's concept of cortical arousal—which has traditionally been assessed by activity in the EEG alpha band—and reviewing literature on the link between extraversion and cortical arousal, it is revealed that there is conflicting evidence. Due to Eysenck's focus on alpha power, scholars have largely neglected higher frequency bands in the EEG signal as indicators of cortical arousal. Based on recent findings, it is suggested that beta power might not only be an indicator of alertness and attention but also a predictor of cognitive task performance. In conclusion, it is proposed that focused music listening prior to cognitive tasks might be a more efficient way to boost performance than listening to background music during cognitive tasks.