Developmental Psychology

Nature

genetics influence the person you become

nurture

life experiences influence the type of person you become

behavioral genetics

the study of how genetic factors influence behaviors, traits, and psychological characteristics

50%

genetic factors account for approximately what percentage of the risk of alcohol dependence

40%

genetic heritability accounts for approximately what percentage of the risk of antisocial and criminal behavior

60%

genetic factors account for approximately what percentage of the variance in IQ

40%

genetic factors account for approximately what percentage of the variance in income

60%

genetic factors account for approximately what percentage of the variance in gpa and college plans

40%

genetic factors account for approximately what percentage of the variance in risk of infidelity and in lifetime number of sexual partners

30%

genetic factors account for approximately what percentage of political attitudes

40%

genetic factors account for approximately what percentage of the variance in how much tv you watch

determinism

philosophical view that all events in the universe, including human decisions and actions, are causally inevitable.

deterministic thinking.

the downside of the behavioral genetics findings

when people are primed to disbelieve in free will they behave dishonestly, support harsher punishment from crimes, engage in less prosocial behavior, exhibit lower empathy toward others, and more racial prejudice toward marginalized groups

why is deterministic thinking a problem?

for virtually any trait, even if there is a statistically significant difference between group averages, it affords miniscule predictive power in comparing individal A to individual B

what is the purpose and logic of this figure?

between groups variability is always miniscule in comparison to within-groups variability.

why is there virtually zero value in prejudiced thinking

Piaget’s stages of cognitive development

jean piaget proposed that cognition develops through distinct stages, each characterized by new ways of interacting with the world

sensorimotor stage

birth → around 2 years

infants primarily learn through sensory-motor experiences and develop object permanence (objects continue to exist when out of sight)

preoperational stage

2-7 years

development of symbolic thought. learn to use language and images to represent objects and animism (attributing life to inanimate objects). experience egocentrism followed by the development of theory of mind. also experience difficulty understanding the brules of conservation which is often due to centration (overly focusing on one dimension).

theory of mind

the ability to have a theory about what’s going on in the mind of others

concrete operational stage

7-11 years

emergence of logical thinking about concrete objects and events and mastery of conservation tasks.

formal operational stage

11 + years

ability to think abstractly and reason hypothetically, development of deductive reasoning and systematic problem solving, and capacity fro cognitively grappling with abstract concepts such as justice, love, or hypothetical scenarios.

major criticisms of piaget’s stages of cognitive development

development is messy and different for every kid. deliberate guidance can speed up development of targeted abilities.

erikson’s psychological stages of development

erik erikson proposed that personality develops through eight sequential stages, in each stage, a central conflict or crisis must be resolved, and
the outcome influences future development.futment

trust vs mistrust

infancy, 0-1 year

Core Conflict: The infant develops trust when caregivers provide consistent care and affection. If caregivers are unreliable or neglectful, the child may develop mistrust.

autonomy vs shame and doubt

1-3 years

Core Conflict: As toddlers begin to explore, they strive for independence. Successful experiences foster autonomy, while excessive criticism or control may lead to feelings of shame and doubt about their abilities.

initiative vs guilt

3-6 years

Core Conflict: During this stage, children assert themselves through initiating activities and interacting with others. When their initiatives are met with encouragement, they develop a sense of purpose; if not, they may experience guilt over their needs and desires.

industry vs inferiority

6-12 years

Core Conflict: Children develop skills and competencies through school and social interactions. Success leads to a sense of industry, while repeated failures or a lack of recognition can result in feelings of inferiority.

identity vs role confusion

12-18 years

Core Conflict: Adolescents explore different roles and ideas to develop a clear sense of self. Success results in a strong identity; failure or confusion can lead to uncertainty about one’s place in society

intimacy and isolation

18-40 years

Core conflict: Young adults seek to form deep, committed relationships. A successful resolution leads to strong bonds with others, while failure may
result in isolation and loneliness.

generativity vs stagnation

40-60 years

Core Conflict: During middle adulthood, individuals focus on contributing to society—through parenting, mentoring, or work—thereby achieving a sense of generativity. A lack of such contributions may lead to stagnation and self-
absorption

ego integrity vs despair

65+ years

Core Conflict: In later years, individuals reflect on their life. A sense of fulfillment and integrity comes from viewing one’s life as well-lived, whereas
regret and bitterness may lead to despair.

narrative fallacy

the tendency to explain complex outcomes with simple causes

1. parental mental health

2. high conflict homes

3. neighborhood safety

4. words spoken per day from parent to child

5. corporal punishment

6. sleep quality/ noise and chaos

7. food insecurity

8. over consumption of refined sugars

9. air pollution/toxins

10. parental praise (process vs traits)

11. preschool attendance

12. family dinners

13. disorganization

14. authoritarian parenting

15. screen time

What are the most impactful environmental
influences on psychological and life outcomes?