Developmental Psychology: is the study of a continuity and change across the life span
Prenatality a Womb with A view:
Prenatal stage of development ends with birth but begins 9 month earlier
As soon as the sperm manages to penetrate through the egg’s protective layer, the egg
quickly releases a chemical that seals and oats all remaining sperm from entering
Zygote: a fertilized egg that contains chromosome from both a sperm and an egg
A zygote has one thing in common with the person it will become-the gender
The sperm and egg contain 23 chromosomes-which become the blueprints. On the 23
chromosome there is a variation in X and Y chromosomes (sperm can carry X-female or
Germinal stage: the 2 week period of prenatal development that begins at conception.
During this stage the zygote begins to divide, and it migrates back down the fallopian
tube and implants itself to the walls of the uterus
Embryonic stage: the period of prenatal development that lasts from the second week
until about the eighth week (cells begin to differentiate as well)
Embryos will X chromosome and Y chromosome produce testosterone-which
masculinizes their reproductive organs. Without testosterone-embryo develops as
Fetal stage: the period of prenatal development that lasts from the ninth week until birth.
You begin to grow the skeleton and the size of the fetus increases
The cells that become the brain divide very quickly. These brain cells also generate
axons and dendrites.
During this stage they undergo myelination: the formation of a fatty sheath around the
axons and the neuron. This helps prevent the leakage of neural signals that travel along
Humans are born with undeveloped brains?
o Because if the baby’s head was big it could not pass through the birth canal.
o The second reason is because our undeveloped brains are specifically shaped
by our unique environment which allows us to adapt.
The womb influences the development-e.g. through the placenta (organ that physically
links the bloodstreams of the mother to the embryo-exchanges material)
o A mother who receives insufficient nutrients during pregnancy can cause health
Almost anything a woman does passes through the placenta.
Teratogens: agents that damage the process of the development (including
environmental poisons- tobacco-second hand smoke)
Fetal Alcohol Syndrome: developmental disorder that stems from heavy alcohol use by
the mother during pregnancy
o FAS can cause brain abnormalities and cognitive defects
The prenatal development is rich with chemicals it also information. The fetus can hear
sounds and become familiar with its mother’s voice.
Infancy and Childhood Becoming A Person
Infancy: the stage of development that begins at birth and last between 18 and 24
months Perceptual and Motor Movement:
Newborns have a limited range of vision (distance of 20 feet)
When visual stimuli are close enough newborns are quite responsive (e.g. suddenly
changing the orientation of the circle)
Newborns are attentive to social stimulis (e.g able to move their head and body parts in
response to the stimulis being presented)
Newborns have shown to mimic facial expression in their first hour of their life
Motor Development: the emergence of the ability to execute physical action (grasping)
Infants are born with some reflexes: specific patterns of motor responses that are
triggered by specific patterns of sensory stimulation
o Sucking reflex (tendency to suck on an object) and rooting reflex (to move their
mouths towards the object) helps them with breastfeeding
Cephalocaudal rule: “top to bottom” rule that describes the tendency for motor skills t
emerge in sequence from the head to the feet
Proximodistal rule: “inside outside” rule that describes the tendency for motor skills to
emerge in the sequence from the periphery.
o E.g. babies learn to control their trunks before their elbows
The timing of these skills are influenced by body weight, baby’s incentive for reaching,
muscular development and general level of activity
Jean Piaget believed that children move throw a stages of cognitive development, which
is the emergence to think and understand.
Between infancy and adulthood, children must come to understand: (3 essential task)
o How the physical world works
o How their minds represent it
o How other minds represent it
Discovering the World:
Piaget believed that cognitive development occurs in 4 stages: sensorimotor,
preoperational, concrete operational and formal operational.
Sensorimotor: a stage of development that begins at birth and last through infancy in
which infants acquire information about the world by sensing it and moving around with
By exploring the environment with their eyes and fingers, the infants begin to construct
schemas: theories about or models of the way that world works
o Key advantage to having theories is that you can predict and control what will
happen in novel situations (e.g. tugging for their toy)
Assimilation: the process by which infants apply their schemas in novel situations
Accommodation: when infants revise their schemas in light of new information
Piaget suggest that infants must acquire some very basic understanding about the
Infants do not have a theory of object permanence: the idea that object continue to
exists even when they are not visible
o The impossible event-infants watched a drawbridge-then lost interest. Then a
box was placed at the back, the studies found they were more intrigued by the
impossible event than the possible events
Infants have some understanding of object permanence by the time they are just 4
Discovering the Mind: the long period following infancy is called childhood: stage of development that begins
at about 18 to 24 months and last until adolescence, which begins between 11 and 14
Childhood consists of 2 stages.
First stage is preoperational stage: the stage of development that begins at the age of
2 years and ends at about 6 years, in which children have a preliminary understanding of
the physical world.
o During this time the child learn about the physical or the concrete objects
Concrete operational stage: the stage of development that begins at about 6 years
and ends at about 11 years, in which children learn how various actions or “operations”
can affect or transform “Concrete” operations.
Experiment: preoperational children are shown equal size glasses filled with same
amount of liquids; they say one has more than the other. But when the content of one
glass is poured into a taller glass-they say volume increase. Concrete operational
understand that volume is the same.
Conservation: the notion that quantitative properties of an object are invariant despite
changes in the object’s appearance.
Why do preoperational children don’t understand the concept of conservation?
Piaget suggest that children have several tendencies to explain their mistakes
o E.g. centration: is the tendency to focus on just one property of an object to
the exclusion of others
o Children also fail to thin about reversibility
The main reason why preoperational children do not understand conservation is
because they do not fully understand that they have minds and that these minds
have mental representation of the world.
Once children make a distinction between mental representation of an objects,
between an objects properties and an object’s appearance, they can understand the
operational changes what an objects look like without changing what it is.
Formal Operational: the stage of development that begins around the age of 11 and
last through adulthood, in which people can solve nonphysical problems
o Childhood ends when this stage begins
o Through this stage people are able to reason out abstract concepts such as
Discovering Other Minds:
Preoperational children do not understand hat they have minds that mentally represent
objects, they also don’t understand that people may have minds that may mentally
represent the same objects in different ways
Egocentrism: the failure to understand that the world appears differently to different
Perception and Beliefs: the false belief test-where a chocolate bar was places in the first
cupboard, but then someone put it in the second cupboard-children claim that they
should look in the second cupboard even though the person did know it was placed
Desires and Emotions: young children seem to understand that other people have
However, children take a long time to understand that other people may have different
reactions unlike their own
About 6 years of age-they begin to understand that others have different knowledge,
they and others may also experience different emotions in the same situation .Theory of Mind: the vast majority of children understand that they and others have
minds that represent the world in different ways
Theory of Mind: the idea that human behaviour is guided by mental representation
o Two groups of children that lag in theory of the mind are autistic children. These
children do not understand that others can have false beliefs, belief-based
emotions or self-conscious emotions
o The second group of children who lag are the mind and deaf children whose
parents that don’t know sign language. The language restricts their development
in understanding the minds of others
Language seems to be a very important indicator at what age the child acquires the
theory of mind.
Language about thoughts and feeling is an important tool for helping children make
sense of their and other’s minds.
Piaget Remixed: Piaget thought that children graduated from one step to another.
Modern psychologist see development as more of a continuous step-like progression
The second claim Piaget made was that children acquire many of these abilities much
earlier than he realized.-He believed that it takes years to overcome egocentrism, but
that is not true
Discovering Our Cultures
Lev vygotsky: he believed that cognitive development was largely the result of the
child’s interactions with members of cognitive development was a result of the child’s
interaction with members of his culture rather than his interactions with concrete objects
He noted that cultural tools, such as language and counting system, influence cognitive
The ability to learn from others depend on three fundamental skills that they acquire:
o The ability to focus on what the other person is focused-point attention
o The ability to use another person’s reaction as information about the world-social
o The ability to do what another person does-or what another person meant to do-
Joint attentions, social referencing and imitation are the three basic skills that allow
infants to learn from other member.
John bowdly: tried to understand how human infants forma attachments to their
He suggested that newborns are not physically developed and thus in order for them to
stay close to their caregivers they cry and make eye contact etc.
Bowdly claimed that babies begin their lives by sending these signals to anyone within
range to receive them, but during the first 6 mont