3 : Themes & Methods in Developmental Psychology
Notes in this color were spoken in class.
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What is developmental psychology?
Developmental psychology is the branch of psychology that studies physical,
cognitive, and social change throughout the lifespan.
In developmental psychology, we see major issues that are continually debated:
● Nature vs. nurture: How does our genetic inheritance (our nature) interact with our
experiences (our nurture) to influence our development?
● Continuity vs. stages: What parts of development are gradual and continuous, like
riding an escalator? What parts change abruptly in separate stages, like climbing rungs
on a ladder?
● Stability vs. change: Which of our traits persist through life? How do we change as we
age?
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
How do we study development?
● Longitudinal Studies: Research that follows and retests the same people over time.
● Cross-Sectional Studies: research that compares people of different ages at the same
point in time.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Physical Development : Influences on Prenatal Development
A growing human is fully dependent on the human it inhabits, and the life they lead and
the choices they make can have a huge impact on the development of their baby. Teratogens
are agents, such as chemicals and viruses, that can reach the embryo or fetus during prenatal
development and cause potential harm:
● Environment → Pollution, toxins, and other environmental factors can disrupt
development.
○ Stress → Stress hormones can cause early delivery.
○ Diet → Pregnant people are encouraged to eat lots of fruits and vegetables, and
discouraged from deli meats, soft cheeses, fish, raw meat/eggs, sugar, spicy
food, and fast food.
● Illness → While you cannot always prevent yourself from getting sick, certain illnesses
should be avoided at all costs while pregnant, as they can affect the development of a
fetus (ex. Zika virus).
● Genetic Mutations → As the embryo develops from a zygote, cells multiply and
chromosomal abnormalities can lead to loss of pregnancy or physical/intellectual
disabilities.
● Hormones → Pregnancy leads to hormonal changes, but imbalances can lead to
miscarriage or premature birth.
● Medicine → Certain medications can cause issues with fetal development.
● Drugs → Drugs and alcohol should be strictly avoided during pregnancy. Fetuses
exposed to certain drugs may experience withdrawal after birth, as well as, serious
health complications and physical abnormalities.
○ Fetal Alcohol Syndrome: physical and cognitive abnormalities in children caused
by excessive drinking during pregnancy
, ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Newborns
Having survived prenatal hazards, we as newborns came equipped with automatic reflex
responses ideally suited for our survival. We withdrew our limbs to escape pain. If a cloth over
our face interfered with our breathing, we turned our head from side to side and swiped at it.
New parents are often in awe of the coordinated sequence of reflexes by which their baby gets
food. When something touches their cheek, babies turn toward that touch, open their mouth,
and vigorously root for a nipple. Finding one, they automatically close on it and begin sucking.
Other adaptive reflexes include the startle reflex (when arms and legs spring out, quickly
followed by fist clenching and loud crying) and the surprisingly strong grasping reflex, both of
which may have helped infants stay close to their caregivers.
Habituation: decreasing responsiveness with repeated stimulation → similar to sensory
adaptation
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Maturation
Maturation is the biological growth processes that enable orderly changes in behavior,
relatively uninfluenced by experience. In other words, regardless of the environment, as long as
a baby is alive, it will continue to grow and develop, though the extent of that development
depends on exterior factors.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Critical Periods
A critical period is a time during someone's development in which a particular skill or
characteristic is believed to be most readily acquired, and if not acquired by a certain time, it
may be impossible to learn.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Motor Development
Notes in this color were spoken in class.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
What is developmental psychology?
Developmental psychology is the branch of psychology that studies physical,
cognitive, and social change throughout the lifespan.
In developmental psychology, we see major issues that are continually debated:
● Nature vs. nurture: How does our genetic inheritance (our nature) interact with our
experiences (our nurture) to influence our development?
● Continuity vs. stages: What parts of development are gradual and continuous, like
riding an escalator? What parts change abruptly in separate stages, like climbing rungs
on a ladder?
● Stability vs. change: Which of our traits persist through life? How do we change as we
age?
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
How do we study development?
● Longitudinal Studies: Research that follows and retests the same people over time.
● Cross-Sectional Studies: research that compares people of different ages at the same
point in time.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Physical Development : Influences on Prenatal Development
A growing human is fully dependent on the human it inhabits, and the life they lead and
the choices they make can have a huge impact on the development of their baby. Teratogens
are agents, such as chemicals and viruses, that can reach the embryo or fetus during prenatal
development and cause potential harm:
● Environment → Pollution, toxins, and other environmental factors can disrupt
development.
○ Stress → Stress hormones can cause early delivery.
○ Diet → Pregnant people are encouraged to eat lots of fruits and vegetables, and
discouraged from deli meats, soft cheeses, fish, raw meat/eggs, sugar, spicy
food, and fast food.
● Illness → While you cannot always prevent yourself from getting sick, certain illnesses
should be avoided at all costs while pregnant, as they can affect the development of a
fetus (ex. Zika virus).
● Genetic Mutations → As the embryo develops from a zygote, cells multiply and
chromosomal abnormalities can lead to loss of pregnancy or physical/intellectual
disabilities.
● Hormones → Pregnancy leads to hormonal changes, but imbalances can lead to
miscarriage or premature birth.
● Medicine → Certain medications can cause issues with fetal development.
● Drugs → Drugs and alcohol should be strictly avoided during pregnancy. Fetuses
exposed to certain drugs may experience withdrawal after birth, as well as, serious
health complications and physical abnormalities.
○ Fetal Alcohol Syndrome: physical and cognitive abnormalities in children caused
by excessive drinking during pregnancy
, ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Newborns
Having survived prenatal hazards, we as newborns came equipped with automatic reflex
responses ideally suited for our survival. We withdrew our limbs to escape pain. If a cloth over
our face interfered with our breathing, we turned our head from side to side and swiped at it.
New parents are often in awe of the coordinated sequence of reflexes by which their baby gets
food. When something touches their cheek, babies turn toward that touch, open their mouth,
and vigorously root for a nipple. Finding one, they automatically close on it and begin sucking.
Other adaptive reflexes include the startle reflex (when arms and legs spring out, quickly
followed by fist clenching and loud crying) and the surprisingly strong grasping reflex, both of
which may have helped infants stay close to their caregivers.
Habituation: decreasing responsiveness with repeated stimulation → similar to sensory
adaptation
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Maturation
Maturation is the biological growth processes that enable orderly changes in behavior,
relatively uninfluenced by experience. In other words, regardless of the environment, as long as
a baby is alive, it will continue to grow and develop, though the extent of that development
depends on exterior factors.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Critical Periods
A critical period is a time during someone's development in which a particular skill or
characteristic is believed to be most readily acquired, and if not acquired by a certain time, it
may be impossible to learn.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Motor Development
