Key Terms

• Personality traits: broad and relatively stable individual differences in feeling, thought, and behavior that tend to differentiate one social actor from the next

• Big 5: most popular current version of trait taxonomies suggests that there are 5 basic groupings, OCEAN

• Openness to experience (O): individual differences in the quality and breadth of a person’s thoughts, interests, and values

• Epigenetics: factors outside the genome that influence how genes are expressed

• Arc of maturation: path followed as personality develops

• Rank-order stability: the extent to which individual differences in a given trait hold steady over time

• Mechanism of manipulation: actively altering environments in order to tailor them to one’s preexisting personality tendencies

• Nonshared environmental effects: environmental factors that are unique to one member of a family as opposed to others, working to make family members differ from each other

• Mechanism of responsivity: actors respond positively to features in their environment that are consistent with their own predispositions, thus reinforcing those predispositions

• Methylation: influenced by factors like aging, viral infections, and processes in the broad environment

• Cognition: how we think

• Roles: highly structured patterns of activity and commitment that are designed to perform essential functions in an ongoing community of human actors

  • May be instrumental (CEO, boss, teacher)

  • May be expressive (mother, son, lover)

  • May entail formal behavioral protocols (POTUS)

  • May entail a set of vague expectations (uncle)

  • May have high social approval (homecoming queen)

  • May have strong social disapproval (class bully)

• Shared environmental effects: effects that all members of a family share that work to make children in the same family similar to each other

• Mean-level change: the extent to which members of the group, on average, tend to increase/decrease on a given dispositional trait as it is tracked over time

• 5-HTTLPR serotonin transporter gene: gene partly responsible for regulating serotonergic function

• DNA methylation: reduces the likelihood of gene transcription, meaning that the gene is there but is silenced and stays unread

Researchers - Theories

• Wendy Johnson: claims that the particular genes that could produce the exact same levels of extraversion in 2 different people are themselves likely to be very different

• Freud: claims that young girls are first attracted to their mothers, then to their fathers, and ultimately take their mother’s sexual orientation. Girls never lose their “penis envy”

• Karen Horney: claims that girls’ attraction to their fathers and disappointment in their mothers reflect their envy of the power that men and boys enjoy in society. She also says that Freud didn’t understand women’s psychology because he could not empathize with the mothering role

Experiments

• O tends to be positively associated with measures of general cognitive ability

• O tends to be associated with loose boundaries of consciousness and odd thinking patterns

• Many empirical findings show that there is long-term stability in traits

• Individual differences in personality traits (Big 5) show substantial rank-order stability

• At least 50% of the variance in personality traits is accounted for by genetic differences between people

• The proportion of trait variation accounted for by genetic differences between people may decline as people get older and as environmental influences of all kinds rise

• The 5-HTTLPR serotonin transporter gene may lead to depression and psychopathology when combined with a history of life stress

• Adolescents who play specific roles in high school (such as being a jock or a brain) tend to adopt similar roles in later life stages such as in college or in their chosen occupational/leisure interests

• An authoritative parenting style tends to be associated with many positive outcomes in children’s lives

• Authoritative parenting tends to predict higher levels of school achievement, moral development, and overall competence in children and adolescents mostly in Western families

• Children raised in authoritative households tend to develop C characteristics (self-discipline and achievement striving) and O characteristics (curiosity, intellectual initiative, and personalized moral standards)

• Studies show that shared environmental effects are almost 0

• MZ twins who differ in their exposure to stressful life events show correspondingly different scores on neuroticism (exposed to more stress = more N)

• Environmental experiences can essentially turn genes on and off

• Rat studies show that poor mothering increases methylation, which turns off genes that are designed to build a healthy stress response system

• In humans, maternal depression and anxiety in the 3rd trimester of pregnancy can lead to increased levels of DNA methylation, which may lead to a compromised stress response system

• People tend to experience increases in C and A and decreases in N as they move from adolescence through late middle age

• People become more A and C but less N because of universal biological changes that accompany aging

• Brain maturation could be responsible for increases in A and C and decreases in N, since the PFC only reaches maturity until 20 years old

• Social roles could be an important factor explaining Big 5 traits arc of maturation

• Young men high in A tend to engage in community service professions and their engagement in these roles further increases their A

• Getting married is associated with above-average increases in emotional stability

• There are cross-cultural differences in the timing of trait change: Norway/Denmark = later, Mexico/Ecuador = earlier

Examples

• High school reunion changes: Mary was an awkward adolescent but was now socially poised, confident, friendly, and sophisticated. Robert stayed the same, very social dominant

• Most personality psychologists believe that the entire universe of traits can be grouped between 2-7 basic regions/clusters of related traits

• Early differences in socioemotional functioning (temperament/personality) have a staying power

• Rank-order stabilities are strongest over short time intervals, and they become weaker when the temporal distance between assessments increases

• Genes interact with environments on many different levels to drive the development of personality traits

• Parents are the most important agents of socialization in any child’s life

• When a gene is unexpressed, a segment of DNA remains like an unopened book, its knowledge locked away

• Augustine of Hippo: was very sexually active, gave up his sexual pursuits, and became a priest

• Jane Fonda: arc of maturation about finding self-acceptance

• Shawn Corey Carter: violent and criminal, loved music, is now Jay-Z