Although the belief that personality is linked to health goes back at least to Greek and Roman times, the scientific study of these links began in earnest only during the last century. The field of psychosomatic medicine, which grew out of psychoanalysis, accepted that the body and the mind were closely connected. By the end of the 20th century, the widespread adoption of the five-factor model of personality and the availability of reliable and valid measures of personality traits transformed the study of personality and health. Of the five broad domains of personality (extraversion, agreeableness, conscientiousness, emotional stability, and intellect/openness), the most consistent findings in relation to health have been obtained for conscientiousness (i.e., hard-working, reliable, self-controlled). People who are more conscientious have better health and live longer lives than those who are less conscientious. These advantages are partly explained by the better health behaviors, good social relationships, and less stress that tend to characterize those who are more conscientious. The causal relation between personality and health may run in both directions; that is, personality influences health, and health influences personality. In addition to disease diagnoses and longevity, changes on biomarkers such as inflammation, cortisol activity, and cellular aging are increasingly used to chart health in relation to personality traits and to test explanatory models. Recognizing that both personality and health change over the life course has promoted longitudinal studies and a life-span approach to the study of personality and health.
Personality and Health
Sarah E. Hampson
Individual Differences at Work
There is a great deal of research on whether personality, ability, and motivation correlate with behavior in the workplace. This is of great importance to all managers who know the benefits of able, engaged, and motivated staff compared to staff who are alienated and disenchanted. The research is an area of applied psychology that is at the interface of work, personality, and social psychology. Predominantly, the research aims to identify measurable characteristics (i.e., personality traits) of an individual that are systematically related to work output and to explain the mechanism and process involved. Research on the relationship among personality and organizational level, promotion level, and salary, all of which are related, is difficult because in order to validate the findings, it is important to get representative and comprehensive measures of work output, which few organizations can provide. The results suggest that personality plays an important part in all the outcomes and that three traits are consistently implicated. The higher people score on trait Conscientiousness and Extraversion and the lower they score on trait Neuroticism, the better they do at work. Similarly, intelligence plays an important role, particularly in more complex jobs. Recent literature has looked at management derailment and failure, with the idea that studying failure can illuminate success, as well as prevent a number of systematic selection errors. This approach is based on “dark-side” traits and the paradoxical finding that some subclinical personality disorders correlate with management success.
Aggression: Risk Factors in the Person and the Situation
Aggressive behavior is defined as social behavior carried out with the intention to harm. Violence denotes those forms of aggression that are intended to cause severe physical harm. Aggressive behavior has severe negative consequences for individuals, social groups, and societies as a whole. Therefore, understanding why some individuals are more prone to engaging in aggressive behavior than others and some situational circumstances and social contexts are more likely to elicit aggressive behavior is a critical task. Influential psychological theories of aggression conceptualize aggression as the result of the interplay between variables in the person and the situation. To explain individual differences in aggressive behavior, one line of research has looked at broad personality dimensions, such as self-esteem and narcissism, lack of self-control, and the “Big-Five” personality factors. Evidence shows that high narcissism, low self-control, low openness to experience, conscientiousness, extraversion, and agreeableness, and high neuroticism are linked to a higher propensity to engage in aggressive behavior. Another line of research has focused on more circumscribed, aggression-related personality constructs, demonstrating that individuals who are habitually anger-prone, have a tendency ruminate about anger-eliciting experiences, and show a hostile attributional style in terms of seeing other persons’ behavior as an expression of hostile intent are more likely to show aggressive behavior. On the side of the situation and social environment, several conditions have been identified under which the likelihood of aggressive behavior is increased. Individuals are more likely to show aggressive behavior when they have consumed alcohol, after they have experienced social rejection by others, when aggressive cues, such as weapons, are present in the situation, and when they have access to a firearm. Aggression is also more likely to be shown under conditions of anonymity and high temperature and as a result of regular exposure to depictions of violence in the media. In addition to such “main effects,” there is evidence of an interactive effect of individual and situational characteristics. For example, the impact of exposure to violent media is greater on individuals with a higher disposition to show aggressive behavior, and the effect of alcohol consumption on aggression is greater among people who are habitually prone to engage in angry rumination. Approaches to preventing aggression may build on the evidence on personal and situational differences. For example, anger management trainings may promote better control of angry impulses, focusing on the personal risk factors for aggression, whereas providing role models who show nonaggressive responses in anger-eliciting situations reflects a focus on situational interventions. In conclusion, personality and situational variables need to be considered in combination and interaction to predict when aggressive behavior is likely to occur. Gaining a better understanding of the factors promoting aggressive behavior needs to remain high on the agenda for theory building and empirical research in psychology.
Theories of Prejudice
Thomas F. Pettigrew
Prejudice, especially intergroup prejudice, has long been a central topic of social psychology. The discipline has sought to be both socially relevant and useful. Thus, theory and research on prejudice fits directly into these central concerns of the discipline. The study of this topic has developed in direct correspondence with how social psychology itself has been able to devise new theoretical and empirical tools—from self-administered questionnaires and probability sample surveys to laboratory experiments and computer-assisted methods. Given the discipline’s intense research interest in intergroup prejudice, it is not surprising that that there is a plethora of theories concerning prejudice. But these many theories tend not to conflict with one another. Rather, they typically coalesce around interrelated themes across three levels of analysis. The micro level of the attitudes of individuals was the primary focus for the first half-century of modern social psychology (1920–1970). Slowly, the field turned its attention to the meso level of intergroup interaction and how such contact influenced intergroup prejudice and discrimination. Finally, the discipline began to consider more systematically the many relevant structural and cultural factors at the macro level of analysis and how they shaped both intergroup prejudice and discrimination. With time, direct links between the three principal levels of analysis have been uncovered. With this order of attention, social psychology boasts many more theories and studies of prejudice at the micro level of individuals than at other levels. But the field has learned that all three levels of analysis are critical for a fully rounded, more complete understanding of the topic.