IB DP Psychology: Option: Developmental psychology – Revision Notes

Course note: these notes follow IB DP Psychology for first assessment 2019, whose last examination session is November 2026. The replacement course is first assessed in May 2027.

Developmental psychology is one of the four IB DP Psychology options, examined on Paper 2 through 22-mark essays. It asks what influences children’s cognitive and social development, how children develop as learners, and how they form an identity – through attachment, gender identity and social roles, and the development of empathy and theory of mind – drawing on biological, cognitive and sociocultural research.

Related: Developmental psychology study guide and practice questions.

Syllabus coverage (first assessment 2019)

Topic	Content
Influences on cognitive and social development	Role of peers and play; childhood trauma and resilience; poverty and socio-economic status
Developing as a learner	Brain development; cognitive development
Developing an identity	Attachment; gender identity and social roles; development of empathy and theory of mind

Key theories

Theory	Claim	Evaluation
Piaget’s stages	Sensorimotor, pre-operational, concrete operational, formal operational; children actively construct knowledge through assimilation and accommodation	Influential and testable; underestimated young children’s abilities; less attention to culture
Vygotsky	Learning is social; the zone of proximal development (ZPD) and scaffolding by more knowledgeable others; play builds self-regulation	Emphasises culture; harder to test precisely
Bowlby’s attachment theory	Infants have an innate need to attach to a caregiver; an internal working model guides later relationships	Supported by animal and human research; critics question monotropy and the critical period
Social learning / gender schema	Gender roles are learned by observation and reinforcement (Bandura); children build gender schemas that organise information (Martin and Halverson, 1981)	Explains cultural variation; biological factors also play a part

Key studies

Study	Finding	Content point
Harlow (1958)	Infant rhesus monkeys preferred a cloth “mother” for comfort over a wire mother that gave milk	Attachment (contact comfort)
Ainsworth et al. (1978)	Strange Situation classified infants as secure, avoidant or resistant; most of the Baltimore sample were secure	Attachment
Van IJzendoorn and Kroonenberg (1988)	Meta-analysis of Strange Situation studies in eight countries: secure attachment most common everywhere; avoidant more common in Germany, resistant in Japan and Israel	Attachment and culture
Hodges and Tizard (1989); Rutter et al. (English and Romanian Adoptees study)	Children raised in institutions showed later social difficulties; children adopted early from Romanian orphanages recovered better than those adopted later	Childhood trauma and resilience
Werner and Smith (Kauai longitudinal study)	About a third of high-risk children grew into competent adults; protective factors included a close bond with a caregiver and community support	Resilience
Luby et al. (2013)	Childhood poverty linked to smaller hippocampal and amygdala volumes, partly through caregiving quality and stressful events	Poverty and brain development
Hart and Risley (1995)	Large differences in the number of words children heard at home by family socio-economic status, linked to vocabulary growth	Poverty and cognitive development
Chugani (1987); Gogtay et al. (2004)	PET and longitudinal MRI studies show brain regions mature at different rates, with the prefrontal cortex maturing last	Brain development
Baron-Cohen, Leslie and Frith (1985)	Most autistic children failed the Sally-Anne false-belief task, unlike most children with Down syndrome and typically developing children	Theory of mind
Wimmer and Perner (1983)	Children typically pass false-belief tasks around age four	Theory of mind
Smith and Lloyd (1978)	Mothers chose gender-typed toys for infants according to the sex they were told the baby was	Gender identity and social roles

Worked example: linking a study to resilience

Question: Explain one study of resilience. [part of a 22-mark essay]

1. Define resilience: positive adaptation despite significant adversity.
2. Study: Werner and Smith followed all children born on the Hawaiian island of Kauai in 1955. Around 30% faced several risk factors such as poverty, family discord or parental mental illness.
3. Finding: about a third of these high-risk children were already developing into competent, caring young adults by age 18, and many others recovered in adulthood.
4. Explanation: protective factors – an easy temperament, at least one close caregiver, school and community support – helped them adapt.
5. Evaluation: long-term longitudinal design and a whole birth cohort; but one community, correlational data and attrition over decades.

Common mistakes / exam traps

• Describing Piaget’s stages without linking them to a question on learning. Focus on what they show about cognitive development.
• Treating attachment types as fixed. Research shows they can change with circumstances.
• Using Harlow without ethical evaluation. Animal research raises ethical issues and questions of generalisation to humans.
• Equating poverty with neglect. Explain mechanisms such as stress, nutrition and language exposure.
• “Gender identity” essays that ignore social roles. The content point includes both.

Frequently asked questions

How is the developmental option examined? On Paper 2: three 22-mark ERQs per option; you answer one at SL, or one from each of two options at HL.

Which theories are essential? Piaget and Vygotsky for cognitive development, Bowlby and Ainsworth for attachment, and at least one explanation of gender identity and of theory of mind.

Can I use studies from the core? Yes, if they are relevant – for example Bandura’s social cognitive theory for gender roles – but link them to development.

Self-test

1. What is the zone of proximal development? The gap between what a child can do alone and with help.
2. Name the three main attachment types in the Strange Situation. Secure, avoidant (insecure-avoidant), resistant (insecure-resistant).
3. What does a false-belief task test? Theory of mind – understanding that others can hold beliefs different from reality.
4. Which brain region matures last? The prefrontal cortex.
5. What is a protective factor? A factor that reduces the effect of adversity, such as a supportive caregiver.