PSY 405 Week 2 Trait Theory and Biological Evidence Example

Conscientious to a Fault: Trait Profiles, Heritability and Temperament in a School Principal

[Student Name]

University of Phoenix

PSY/405: Theories of Personality

Week 2 Assignment

[Instructor Name]

[Date]

The principal and her history are composites written for a model paper; theory and research come from the sources listed.

Where Week 1 looked for hidden conflicts, trait theory looks at stable, measurable tendencies that distinguish one person from another. Biological approaches ask where those tendencies come from. This paper profiles the composite principal from Week 1, Renée Castillo, in trait terms and examines what genetic and temperament research add.

The Five-Factor Model

Trait theorists from Allport through Cattell and Eysenck sought the basic dimensions of personality. The five-factor model, now the most widely used, sorts personality into five broad dimensions, from curiosity and organization to sociability, warmth and emotional reactivity, and places every person somewhere along each one. Traits are measured mainly by self-report questionnaires and ratings from close acquaintances.

Renée's Trait Profile

Based on her own ratings and those of her assistant principal, Renée's profile would look like this. Conscientiousness is very high: she is organized, persistent and self-disciplined, and her standards are exacting. Extraversion is high: she draws energy from assemblies, meetings and students. Agreeableness is high with students and families but lower with staff under stress. Neuroticism is moderately high: she worries, ruminates at night and reacts strongly to criticism. Openness is moderate: she adopts new programs that have evidence behind them but distrusts fads.

Do Traits Predict Outcomes?

Roberts et al. (2007) gathered prospective longitudinal studies to compare personality traits with socioeconomic status and cognitive ability as predictors of mortality, divorce and occupational attainment. Traits predicted all three outcomes, and their effects matched those of family income, education and test scores in size. Higher conscientiousness, for instance, was linked to longer life and higher occupational attainment, while neuroticism was linked to divorce.

Renée's career fits this research: her conscientiousness helped carry her from a family restaurant kitchen to a principal's office. Her moderately high neuroticism, however, is the trait most associated with distress under stress, which fits her sleepless nights since the rating drop.

Measuring the Profile Well

A single self-report can mislead. Renée rated her own agreeableness higher than her assistant principal did, since she judges herself by her warmth with students while staff see her pressure. Combining self-ratings with ratings from people who know her in different settings, a teacher, a parent volunteer and her sister, gives a sturdier profile. Trait researchers favor this multi-rater approach because each observer sees a different slice of behavior, and agreement among them is stronger evidence than any one view.

Facets Within the Factors

Each broad factor contains narrower facets. Within conscientiousness, Renée scores highest on achievement striving and dutifulness and somewhat lower on deliberation, since she acts quickly under pressure. Within neuroticism, her highest facet is self-consciousness, the sting of being judged, which fits her reaction to a public rating more closely than general anxiety does.

The Person and the Situation

Critics once argued that traits predict behavior in any single situation only weakly. The answer that emerged is that traits predict average behavior across many situations well, while situations shape behavior in any one moment. Renée's agreeableness drops in high-pressure staff meetings but remains high across her week, a pattern the trait view expects.

How Much Is Genetic?

Polderman et al. (2015) gathered nearly every twin study from 1958 to 2012, about fourteen and a half million pairs and almost every trait ever measured in twins. Across all traits, the average heritability was about forty-nine percent, and for most traits, the pattern of twin similarity fit a simple model in which genes add up rather than interact in complex ways. Personality traits fell in a similar range.

Heritability describes a population, not a person. It means that, in the populations studied, about half of the differences among people in a trait went along with genetic differences. The figure cannot be read as saying half of Renée's conscientiousness came from her genes, and it says nothing about whether the trait can change.

A heritability of about one half tells us about differences among many people; it cannot split Renée's drive into a genetic half and a kitchen half.

Temperament: Early Biological Tendencies

Kagan and Snidman (1991) observed infants' reactions to unfamiliar sights, sounds and smells and identified a group who reacted with high motor activity and distress and another who stayed relaxed. Highly reactive infants were more likely to become shy, cautious toddlers, while low-reactive infants tended to become sociable and bold. The groups also differed in physiological measures such as heart rate, suggesting biological roots for these early styles. Many children, however, moved toward the middle over time, showing that temperament is a tendency, not a destiny.

Renée's mother describes her as an intense baby who cried at loud noises but who became bold and outgoing by school age, possibly helped by early responsibility at the restaurant. Her adult pattern, outward confidence with inner reactivity to criticism, may reflect a reactive temperament channeled by experience into achievement.

Genes Work Through Environments

Genetic tendencies do not operate in isolation. A conscientious child may seek out responsibility, and parents may give more responsibility to a reliable child, so genes and environment become intertwined. Renée's father's demands and her early duties likely amplified an inborn persistence. Research on adult development also shows that conscientiousness and agreeableness tend to rise and neuroticism to fall with age, so traits are stable but not frozen.

What Traits Explain and What They Miss

The trait view describes Renée precisely and predicts her success and her vulnerability to stress. It is less able to explain why the rating drop hurts her so specifically, which the Week 1 reading attributed to an idealized self, or how her thinking about the rating could change. Traits describe what she tends to do; later weeks will examine the beliefs, goals and meanings that explain why.

Conclusion

Renée's trait profile, very high conscientiousness, high extraversion and agreeableness and moderately high neuroticism, fits both her achievements and her distress. Research shows that such traits predict real outcomes, that about half of trait variation across people is associated with genes and that early temperament shapes but does not fix adult personality. The trait and biological view adds precision and evidence to the psychodynamic reading, while leaving the meaning of her struggle for other perspectives.

References

Kagan, J., & Snidman, N. (1991). Temperamental factors in human development. American Psychologist, 46(8), 856-862. https://doi.org/10.1037/0003-066X.46.8.856

Polderman, T. J. C., Benyamin, B., de Leeuw, C. A., Sullivan, P. F., van Bochoven, A., Visscher, P. M., & Posthuma, D. (2015). Meta-analysis of the heritability of human traits based on fifty years of twin studies. Nature Genetics, 47(7), 702-709. https://doi.org/10.1038/ng.3285

Roberts, B. W., Kuncel, N. R., Shiner, R., Caspi, A., & Goldberg, L. R. (2007). The power of personality: The comparative validity of personality traits, socioeconomic status, and cognitive ability for predicting important life outcomes. Perspectives on Psychological Science, 2(4), 313-345. https://doi.org/10.1111/j.1745-6916.2007.00047.x