Developmental psychology explores how our behaviors and thoughts change throughout... Show more
AP Psychology194 views·Updated Jun 2, 2026·4 pagesExploring Developmental Psychology
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Foundations of Development
Our journey begins before birth, with genetics playing a crucial role. A zygote (fertilized egg) develops into an embryo and later a fetus that can respond to sound by six months. During the critical period, harmful substances called teratogens can damage the developing baby if the mother ingests them.
Newborns come equipped with several reflexes - involuntary reactions like sucking, swallowing, and the rooting reflex (turning their head when touched on the cheek). Their senses are developing at different rates - they can hear before birth but are born with underdeveloped vision (essentially "legally blind").
Motor development follows a predictable pattern as babies learn to roll over around 5½ months, stand at 8-9 months, and walk independently by 15 months. This development occurs through maturation - biological growth processes that happen naturally with minimal influence from experience.
💡 Quick Fact: Attachment, the emotional bond between infant and caregiver, is so important that babies often prefer contact comfort (touching something soft) over food when stressed, as shown in Harry Harlow's famous monkey experiments!
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Attachment & Parenting Styles
Researchers like Harry Harlow and Mary Ainsworth revolutionized our understanding of attachment. Harlow's famous monkey studies showed that baby monkeys preferred soft surrogate "mothers" over wire ones that provided food, demonstrating the importance of contact comfort. Ainsworth identified three attachment patterns through the "strange situation" test:
Most babies show secure attachment - they're confident when parents are present and seek comfort when they return after an absence. Others display avoidant attachment (resist being held, don't seek comfort) or anxious/ambivalent attachment (show distress when alone but resist comfort when parents return).
Psychologist Diana Baumrind identified three distinct parenting styles that affect development. Authoritarian parents enforce strict rules with punishment, while permissive parents provide few consistent guidelines. The most effective approach is the authoritative style, where parents set reasonable standards with explanations and balance praise with discipline.
🧠 Think About It: Your attachment style and your parents' approach to discipline likely shaped your own comfort with relationships and authority. Can you identify which patterns you experienced growing up?
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Psychological Development Theories
Sigmund Freud proposed that personality develops through psychosexual stages, where conflicts can cause fixation at particular stages. These include the oral stage , anal stage (1-3), phallic stage (3-5), latency period , and genital stage (puberty onward). Each stage focuses on different body areas as sources of pleasure and psychological development.
Erik Erikson expanded on Freud's work with his psychosocial stage theory, focusing on how social interactions shape identity. Each stage presents a specific challenge, from trust vs. mistrust in infancy to integrity vs. despair in old age. Successfully resolving each stage's conflict builds psychological strength for future challenges.
Jean Piaget revolutionized our understanding of children's thinking with his four stages of cognitive development. He discovered that children of similar ages often make similar "mistakes" in reasoning. His stages include the sensorimotor stage , preoperational stage , concrete operational stage (8-12, developing logical thinking and understanding conservation), and formal operational stage .
👉 Remember: Piaget's theory has been criticized for underestimating children's abilities - many children progress through these stages faster than he predicted!
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Moral Development
Lawrence Kohlberg proposed that moral reasoning develops through three distinct levels. The pre-conventional level focuses on avoiding punishment and gaining rewards. The conventional level emphasizes following social rules and norms. Finally, the post-conventional level involves understanding universal ethical principles beyond specific rules.
Kohlberg's theory faced criticism for not adequately sampling females in his research. Carol Gilligan addressed this gap by studying girls' responses to moral dilemmas like the "Heinz question" (whether a man should steal medicine for his dying wife). She found that girls typically scored lower on Kohlberg's scale but suggested this wasn't due to less developed morality.
Gilligan argued that girls tend to consider situational factors and relationships more carefully, while boys often use more absolute moral judgments. This gender difference highlights how moral reasoning can vary based on different priorities and perspectives.
🔍 Important Insight: The development of morality isn't just about learning rules - it reflects deeper cognitive development, social understanding, and even gender differences in how we approach ethical problems.
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AP Psychology194 views·Updated Jun 2, 2026·4 pagesExploring Developmental Psychology
Developmental psychology explores how our behaviors and thoughts change throughout life, from conception to death. This fascinating field examines key debates like nature vs. nurture and whether development occurs continuously or in distinct stages. Understanding how we develop helps explain... Show more
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Foundations of Development
Our journey begins before birth, with genetics playing a crucial role. A zygote (fertilized egg) develops into an embryo and later a fetus that can respond to sound by six months. During the critical period, harmful substances called teratogens can damage the developing baby if the mother ingests them.
Newborns come equipped with several reflexes - involuntary reactions like sucking, swallowing, and the rooting reflex (turning their head when touched on the cheek). Their senses are developing at different rates - they can hear before birth but are born with underdeveloped vision (essentially "legally blind").
Motor development follows a predictable pattern as babies learn to roll over around 5½ months, stand at 8-9 months, and walk independently by 15 months. This development occurs through maturation - biological growth processes that happen naturally with minimal influence from experience.
💡 Quick Fact: Attachment, the emotional bond between infant and caregiver, is so important that babies often prefer contact comfort (touching something soft) over food when stressed, as shown in Harry Harlow's famous monkey experiments!
2
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Attachment & Parenting Styles
Researchers like Harry Harlow and Mary Ainsworth revolutionized our understanding of attachment. Harlow's famous monkey studies showed that baby monkeys preferred soft surrogate "mothers" over wire ones that provided food, demonstrating the importance of contact comfort. Ainsworth identified three attachment patterns through the "strange situation" test:
Most babies show secure attachment - they're confident when parents are present and seek comfort when they return after an absence. Others display avoidant attachment (resist being held, don't seek comfort) or anxious/ambivalent attachment (show distress when alone but resist comfort when parents return).
Psychologist Diana Baumrind identified three distinct parenting styles that affect development. Authoritarian parents enforce strict rules with punishment, while permissive parents provide few consistent guidelines. The most effective approach is the authoritative style, where parents set reasonable standards with explanations and balance praise with discipline.
🧠 Think About It: Your attachment style and your parents' approach to discipline likely shaped your own comfort with relationships and authority. Can you identify which patterns you experienced growing up?
3
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Psychological Development Theories
Sigmund Freud proposed that personality develops through psychosexual stages, where conflicts can cause fixation at particular stages. These include the oral stage , anal stage (1-3), phallic stage (3-5), latency period , and genital stage (puberty onward). Each stage focuses on different body areas as sources of pleasure and psychological development.
Erik Erikson expanded on Freud's work with his psychosocial stage theory, focusing on how social interactions shape identity. Each stage presents a specific challenge, from trust vs. mistrust in infancy to integrity vs. despair in old age. Successfully resolving each stage's conflict builds psychological strength for future challenges.
Jean Piaget revolutionized our understanding of children's thinking with his four stages of cognitive development. He discovered that children of similar ages often make similar "mistakes" in reasoning. His stages include the sensorimotor stage , preoperational stage , concrete operational stage (8-12, developing logical thinking and understanding conservation), and formal operational stage .
👉 Remember: Piaget's theory has been criticized for underestimating children's abilities - many children progress through these stages faster than he predicted!
4
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Moral Development
Lawrence Kohlberg proposed that moral reasoning develops through three distinct levels. The pre-conventional level focuses on avoiding punishment and gaining rewards. The conventional level emphasizes following social rules and norms. Finally, the post-conventional level involves understanding universal ethical principles beyond specific rules.
Kohlberg's theory faced criticism for not adequately sampling females in his research. Carol Gilligan addressed this gap by studying girls' responses to moral dilemmas like the "Heinz question" (whether a man should steal medicine for his dying wife). She found that girls typically scored lower on Kohlberg's scale but suggested this wasn't due to less developed morality.
Gilligan argued that girls tend to consider situational factors and relationships more carefully, while boys often use more absolute moral judgments. This gender difference highlights how moral reasoning can vary based on different priorities and perspectives.
🔍 Important Insight: The development of morality isn't just about learning rules - it reflects deeper cognitive development, social understanding, and even gender differences in how we approach ethical problems.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Similar Content
Most popular content: Lawrence Kohlberg
1Most popular content in AP Psychology
9Most popular content
9Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.6/5App Store
4.7/5Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan SiOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha KlichAndroid user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
AnnaiOS user