Development
Developmental Psych – what is it?
 Branch of psychology that studies physical, cognitive, and
social change throughout the life span
 Much research centers on three issues:
 Nature vs. nurture – how do genetic inheritance and
experience influence development?
 Continuity and stages – is development gradual and
continuous or does it proceed through a series of stages?
 Stability and change – do our early personality traits
persist through life or do we become different people as
we age?
Prenatal Development and the Newborn
 Prenatal development
 zygote – fertilized egg; conception to two weeks
 embryo – developing human organism from 2 weeks after
conception through 2nd month
 fetus – developing human organism from 9 weeks after conception
to birth
 teratogens – harmful substances (chemicals, viruses) that can cause
harm to the embryo or fetus during prenatal development
 fetal alcohol syndrome – physical and cognitive abnormalities in
children caused by heavy drinking during pregnancy
 Newborn
Researchers study what babies are
capable of through habituation – a
decrease in responding with repeated
stimulation
 Infant pays attention to a new stimulus but
loses interest the more often it is presented
Infancy and Childhood:
Physical development
 Brain development
 Have most of the brain cells
you’ll ever have at birth but
neural networks grow with age
 Association areas (linked with
thinking, memory and
language) are last to develop
 Motor development
 Sequence is universal (roll over,
sit, crawl, walk) but there are
individual differences in timing
 Genes play a major role in
motor development
 Infantile amnesia - our
earliest memories
seldom predate our 3rd
birthday
 Hippocampus is not
yet developed
 Toddlers don’t have
the language to index
memory
Infancy and Childhood:
Cognitive Development
 Jean Piaget
 Believed the mind was not a miniature model of an adult but
developed in a series of stages
 Maturing brain builds schemas - concept or framework that
organizes and interprets information
 Assimilation - interpreting new experiences in terms of our existing
schemas
 Thinking all four-legged animals are cows
 Accommodation - adjusting our current understandings (schemas)
to incorporate new information
 Adjusting schema for four-legged animal to include a moose
 Piaget’s four stages of
cognitive development
 Sensorimotor stage birth to nearly age 2
 Babies take in the world
through their senses and
actions
 Young infants lack object
permanence - awareness
that things continue to
exist even when not
perceived
 Develops by 8 months
but gradually
 Preoperational stage - age 2 to 7
 Child learns to use language but doesn’t yet
comprehend the mental operations of concrete logic
 Develop conservation - principle that properties (mass,
volume and number) remain the same despite changes
in the forms of objects
 Display egocentrism - difficulty in taking another’s view
 Lose this when they develop theory of mind - the
ability to take another’s perspective
The impossible outcome
Theory of mind
 Concrete operational - 6 or 7 to 11
 Children gain the mental operations that enable them to think
logically about concrete events
 Can understand conservation and mathematical transformations
 Formal operational - age 12 on
 Children begin to think logically about abstract concepts
 Piaget’s legacy
 Identified specific milestones and sparked interest in cognitive
development
 Today’s researchers see development as more continuous
 See formal logic as a smaller part of cognition
Infancy and childhood:
Social Development
 Around 8 months infants
develop stranger anxiety - fear
of strangers
 Peaks around 13 months
 Develop attachment with
caregivers who provide them
with love and comfort
 Harlow monkey study (1950s)
 Critical period - optimal period
shortly after birth when an
organism’s exposure to certain
stimuli or experiences
produces proper development

Children prefer familiarity
 Attachment Differences: Temperament and Parenting
 Mary Ainsworth’s strange situation
 Secure attachment
 60%
 Play in mother’s presence
 Are distressed when she leaves
 Seek contact with her when she comes back
 Insecure attachment
 Less likely to explore and may cling to mom
 Either cry or are indifferent when she leaves and returns
 Is attachment the result of parenting or temperament -
characteristic emotional reactivity and intensity
 Many researchers believe early attachments form foundation for our
adult relationships

Most abusers were abused as children but most abused children do not
become abusive adults
 Self-concept - our understanding and evaluation of who we are
 Developed by age 12
 Parenting styles
 Authoritarian - impose rules and expect obedience
 Permissive - submit to children’s wishes; make few demands and use
little punishment
 Authoritative - demanding and responsive

Results in highest self-esteem, self-reliance and social competence
Nature of Gender
 X chromosome - sex chromosome found in both men
and women; females have 2, men have 1
 Y chromosome - sex chromosome found only in men
 Triggers production of the testes and testosterone
Nurture of Gender
 Role - set of expectations about a social position defining
how those in that position ought to behave
 Gender role - set of expected behaviors for males or for
females
 Gender identity - our sense of being male or female
 Gender typing - acquisition of a traditional masculine or
feminine role
 Social learning theory - theory that we learn social behavior
by observing and imitating and by being rewarded or
punished
Adolescence: Physical development
 Transition period from childhood
to adulthood
 Primary sex characteristics - body
structures (ovaries, testes, and
external genetalia) that make
sexual reproduction possible
 Secondary sex characteristics -
nonreproductive sexual
characteristics, such as female
breasts and hips and male voice
quality and body hair
 Menarche - first menstrual period
Adolescence:
Cognitive development
 Lawrence Kohlberg’s Levels of Morality:
 Preconventional morality

Before age 9
 Focused primarily on self-interests
 Obey rules to either avoid punishment or gain rewards
 Conventional morality
 Early adolescence
 Focuses on caring for others
 Uphold laws and social rules, simply because they are laws and social rules
 Postconventional morality
 Actions are judged “right” because they flow from people’s rights or from
self-defined, basic ethical principles
 Jonathan Haidt’s social intuitionist account of morality
 Moral feelings precede moral reasoning
Erikson’s Stages of Psychosocial
Development
Adulthood: Physical development
 Menopause - time of natural cessation of menstruation
 Usually within a few years of 50
 Men experience no equivalent but do experience a gradual decline in
sperm count
 Distance perception and adaptation, vision muscle strength,
reaction time, stamina, sense of smell and hearing decrease with
age
 Become more susceptible to life-threatening ailments (cancer,
pneumonia) but less susceptible to short-term ailments
 Alzheimers - loss of brain cells and deterioration of neurons that
produce acetylcholine
Adulthood: Cognitive development
 Cross-sectional study - study in
which people of different ages are
compared with one another
 Longitudinal study - research in
which the same people are
restudied and retested over a long
period
 Crystallized intelligence - our
accumulated knowledge and
verbal skills

Tends to increase with age
 Fluid intelligence - our ability to
reason speedily and abstractly

Tends to decrease during late
adulthood
Adulthood: Social development
 Social clock - culturally preferred timing of
social events such as marriage, parenthood and
retirement