Child Dev Mid 1

Plato and Aristotle

Thought that schools and parents had responsibilities for teaching kids the self-control that would make them effective citizens

Plato

Believed children are born with knowledge already inside them. He thought our senses can be unreliable, so experiences don’t create knowledge—they simply trigger knowledge that was already present from birth.

Aristotle

Children gain knowledge gradually through their sensory experiences, meaning the child’s mind starts as a blank tablet.

John Locke

Believed babies are born as a “blank slate” (tabula rasa) and that their experiences shape who they become. Parents should guide, reward, and discipline children, while gradually giving them more independence as they grow.

Jean-Jacques Rousseau

Believed children are born with an innate sense of justice and morality that develops naturally as they grow. He believed children go through stages such as infancy, childhood, and adolescence, and that parents should be responsible and responsive to their children’s needs.

Industrial Revolution

England became more urban and factory-based. Many children moved to cities and worked long hours in dangerous factories and mines for very little pay, with some being seriously injured or killed. Reformers pushed for laws limiting child labour and increasing education, and by the 1800s, child labour had become a major national concern.

5 major theoretical perspectives in child-development research

Biological

Psychodynamic

Learning

Cognitive-development

Contextual Perspectives

The Biological Perspective

Intellectual, personality, physical, and motor development are influenced by biology.

• Manturational Theory

• Ethological theory

Maturational Theory

Children develop according to a prearranged biological plan in the body. Gesell believed development naturally unfolds over time, so parents should let children develop at their own pace.

Eventually rejected because it did not explain how the environment affects development.

Ethological Theory

Explains development from an evolutionary perspective. It suggests that many behaviours are inherited because they have survival value, such as babies crying or clinging to get care from adults. It also says that certain types of learning are easier during specific ages.

Lorenz and the baby geese

Critical Period

Time when a specific type of learning can take place; before or after this period, the same learning is difficult or impossible (Ethological Theory)

The Psychodynamic Perspective

Oldest scientific perspective on child development

Freuds psychodynamic theory

Three components of personality that emerge at distinct ages

Id: The part of personality present at birth that seeks immediate satisfaction of basic needs and wants.

Ego: The practical and rational part of personality that helps balance the id’s desires with the demands of reality.

Superego: The moral part of personality that develops as children learn right and wrong.

Freuds stages of development

Focused on different bodily needs and conflicts.

Oral stage: Birth–2 years. Children explore and experience pleasure mainly through the mouth.

Anal stage: 2–3 years. Development is focused on toilet training.

Phallic stage: 3–7 years. Children become aware of differences between the sexes.

Latency stage: 7–11 years. Energy is focused on activities such as school, friendships, and athletics.

Genital stage: 11 years–adulthood. Development involves mature sexuality.

Freuds 2 insights that had a lasting impact on child development research

• Early experiences can have long-lasting effects on development.

• Children often experience a conflict between what they want to do and what they know they should do.

Eriksons Psychosocial Theory

Development happens through a series of stages, with each stage involving a unique challenge or crisis.

• Basic trust vs mistrust (birth–1): Learn that the world is safe and trustworthy.

• Autonomy vs shame and doubt (1–3): Develop independence and learn to make decisions.

• Initiative vs guilt (3–7): Become willing to try new things and handle failure.

• Industry vs inferiority (6–adolescence): Learn skills and how to work with others.

• Identity vs identity confusion (adolescence): Develop a clear and lasting sense of who you are.

• Intimacy vs isolation (young adulthood): Form loving and committed relationships.

• Generativity vs stagnation (middle adulthood): Contribute to younger generations through parenting, childcare, work, or other activities.

• Integrity vs despair (late life): Look back on life and feel that it was meaningful and worthwhile.

John B. Watson

One of the first theorists to apply the learning perspective to child development. He believed that experience was the main factor shaping what children become, and that with the right methods, almost anything could be learned.

He studied classical conditioning and applied this idea to humans and showed that fear could be learned through conditioning, most famously in the Little Albert study.

Classical Conditioning

Pavlov and the dogs salivating

Skinner

Skinner studied operant conditioning, which means that the consequences of a behaviour affect whether it happens again.

Reinforcement vs Punishment

Reinforcement makes a behaviour more likely to happen again, while punishment makes it less likely.

Positive Reinforcement vs Negative Reinforcement

Positive reinforcement means giving a reward for good behaviour, while negative reinforcement means taking away something unpleasant to encourage a behaviour.

Positive Punishment vs Negative Punishment

Positive punishment adds something unpleasant, while negative punishment takes away something pleasant to reduce a behaviour.

Social Cognitive Theory

Albert Bandura developed social cognitive theory, which says children learn by watching and imitating others, especially when the person is admired or the behaviour is rewarded. He believed children actively think about and understand what they observe, and that self-efficacy (beliefs about their own abilities) affects what they choose to imitate.

The Cognitive-Developmental Perspective

• Focuses on how children think and how their thinking changes as they grow 

Jean Piaget

Piaget believed children naturally try to understand their world by creating and testing theories based on their experiences. When something doesn’t match their expectations, they revise their theories, sometimes making major changes. He believed these major changes happen around ages 2, 7, and before adolescence, leading to four stages where children’s thinking becomes increasingly sophisticated.

Piagets 4 stages of cognitive development

Sensorimotor (birth–2): Babies learn through their senses and movements and eventually develop mental representations.

Preoperational (2–7): Children use symbols to represent the world but mainly see things from their own perspective.

Concrete operational (7–11): Children can use logical thinking about things they can directly experience in the here and now.

Formal operational (adolescence+): Teens and adults can think abstractly, consider hypothetical situations, and use logical reasoning.

Overall, Piaget believed children’s thinking becomes more sophisticated as they develop.

The Contextual Perspective

The environment plays an important role in a child’s development, including influences from parents and siblings. Culture is the shared knowledge, attitudes, behaviours, traditions, and values of a group. Culture provides an important context for a child’s development.

Vygotskys Theory of Contextual Development

One of the first theorists to emphasize the importance of culture in child development. He believed adults pass on their culture’s beliefs, customs, and skills to children, and that children develop through an apprenticeship where they learn by working with skilled adults. He also viewed families as a system, where parents and children influence each other and are influenced by extended family and friends.

Bronfenbrenner’s Theory of Ecological Systems 

Bronfenbrenner’s ecological systems theory says that children develop within five connected systems that influence each other.

Microsystem includes people and things closest to the child, like parents and school.

Mesosystem is how different parts of the child’s life affect each other.

Exosystem includes settings the child doesn’t directly experience, but that still affect them.

Macrosystem includes the larger culture and society around the child.

Chronosystem refers to how all of these systems change over time.

Continuity of Development

The continuity vs. discontinuity issue asks whether development is predictable over time. The continuous view says that once a child starts on a certain developmental path, they generally stay on that path throughout life. However, neither view is completely accurate because development is not perfectly predictable.

Nature and Nurture

The nature-nurture issue looks at how biology (nature) and the environment (nurture) influence child development. Scientists now understand that development is shaped by both heredity and environment, rather than being caused entirely by one or the other.

Active-passive

Asks whether children are simply shaped by their environment or actively influence their own development.

Today, researchers believe children and their environments influence each other, meaning development is a two-way process.

Systematic Observation

Involves watching children and carefully recording what they do

Two types: Naturalistic and structured

Naturalistic Observation

In naturalistic observation, children are watched as they behave naturally in a real-life setting. Researchers decide what behaviours to record and how to measure them. A nominal scale groups behaviours into categories, while a checklist is a prepared list of behaviours or characteristics to look for.

Structured Observation

In structured observation, researchers create a situation that is likely to produce the behaviour they want to study. It is useful for behaviours that are rare or usually happen in private, but researchers must make sure the setting does not change the behaviour they are studying.

Two forms of bias for systematic observation

Observer bias occurs when researchers notice or interpret behaviours in ways that support their hypothesis. The expectancy effect is when the observer’s expectations influence what they see. Inter-rater reliability checks for bias by having two observers record the same behaviours and comparing their results.

Observer influence occurs when participants change their behaviour because they know they are being watched, while habituation helps by allowing participants to get used to the researcher’s presence.

Sample Behaviour with Tasks

Involve creating tasks that are meant to measure a specific behaviour.

Convenient, but the task may not accurately represent the behaviour being studied.

Self-Reports

Self-reports are children’s answers to questions about a topic. Written questions are called questionnaires, while spoken questions are called interviews. They are convenient and provide direct information, but answers may be inaccurate because people forget events or experience response bias, where they choose answers they think are more socially acceptable.

Physiological Measures

Physiological measures involve measuring children’s physical responses to understand their behaviour. For example, heart rate can show attention, while cortisol levels in saliva can indicate stress. These measures usually focus on a specific aspect of behaviour and are often used with other research methods.

Construct Validity

Means the test actually measures the concept it is supposed to measure.

A test designed to measure anxiety actually measures anxiety, not something else like sadness.

Concurrent Validity

means the test actually measures the concept it is supposed to measure.

• A new reading test gives similar results to an already established reading test.

Correlational Studies

A correlational study looks at how two variables are related naturally. The relationship is measured using a correlation coefficient (r), which ranges from -1.0 to +1.0.

The closer r is to 0, the weaker the relationship; the closer it is to -1 or +1, the stronger it is. However, correlation does not show cause and effect

Positive Correlation

A positive correlation means both variables increase together,.

Negative Correlation

Means one increases as the other decreases.

Experimental Studies

Study where a researcher changes a factor to see if it causes a change in behaviour.

Often done in laboratory settings so researchers can control other factors, but this can make the situation feel artificial.

Independent Variable

The factor that the researcher changes or controls.

Dependent Variable

The behaviour or outcome that the researcher measures.

Inferential Statistics

Statistics used to analyze results and draw conclusions.

Null Hypothesis

The idea that the experiment had no effect and that any results happened by chance

Field Experiment

A field experiment is when researchers change the independent variable in a natural, real-world setting. This makes the results more realistic and still allows researchers to study cause and effect. However, field experiments can be difficult to carry out because researchers have less control and people may not want to change their normal routines for the study.

Longitudinal Study

Follows the same people over a period of time, testing or observing them at different points in their lives. This allows researchers to directly see how development changes and how earlier experiences may affect people later in life. These studies usually last for years, but they can also be shorter.

Microgenetic Study

Type of longitudinal study where children are tested repeatedly over days or weeks to closely observe a specific developmental change as it happens.

Disagvantages of longitudinal studies

Cost, Practive affect, selective attrition, cohort effect

Practice effect

when children become familiar with the tests and get better at taking them, rather than actually improving in the skill being measured.

Selective attrition

when some participants drop out of the study, which can change the results.

Cohort effect

when the changes researchers observe are specific to a particular generation or group of people, rather than being true for everyone.

Cross-Sectional Design

Looks at children of different ages at the same point in time. For example, researchers might compare 6-, 9-, and 12-year-olds without waiting years to study them. This is faster than a longitudinal study and avoids problems like practice effects and selective attrition.

Disadvantages of Cross-Sectional Design

Results may only apply to the specific generation of children being studied and may not apply to children in the past or future.

Also, because children are only tested once, researchers cannot see how their development changes over time or whether development is continuous.

Longitudinal-Sequential Design

A sequential study combines longitudinal and cross-sectional methods. Researchers study different age groups over time. For example, they might test 6- and 9-year-olds, then test the same groups again 3 years later. This helps researchers identify whether practice effects or cohort effects are affecting the results.

Meta-Analysis

A meta-analysis combines the results of many different studies on the same topic to find overall patterns or relationships between variables. Researchers compare the results and methods used in the studies to see whether a finding applies across different studies. It can also show research gaps and how different research methods affect the results.

Guidelines included in all major ethic codes

• Seek to do research that benefits humanity

• Minimize risks to research participants

• Describe the research to potential participants so they can determine whether they wish to participate 

• Avoid deception

• Keep results anonymous or confidential

• Give a debriefing afterward

Research Ethics Board

5 members: 2 must understand the particular field of research, and 1 must know ethics 

Chromosome

Tiny structures in the nucleus that contain genetic material

Louise Brown

Did the first “test tube baby”

Vitri Fertilization (IVF)

Involved mixing sperm and egg together in a dish, and then placing a few of these eggs in the uterus

Only 1/3 succeed

Cystic Fibrosis

Excess mucus clogs the respiratory and digestive tracts. Lung infections are common

Phenylketonuria

Phenylalanine, an amino acid, accumulated in the body and damages the NS, causing intellectual disabilities 

Albinism

Tissues lack melanin; in the eyes this causes visual problems and extreme sensitivity to light 

Tay-Sach Disease

The NS degenerated in infancy, causing deafness, blindness, intellectual disability, and, during the preschool years, death

Behavioural Genetics

Branch of genetics that deals with the inheritance of behavioural and psychological traits 

Period of the Zygote

The period of the zygote (weeks 1–2) begins when the egg is fertilized. The zygote quickly divides into more cells as it travels through the fallopian tube toward the uterus. After about 4 days, it becomes a blastocyst. The blastocyst reaches the uterus and implants into the uterine wall. Some cells become the baby, while others form structures that support the baby, including the placenta. The zygote period ends when implantation and cell differentiation are complete.

Germ disc

Small cluster of cells near the center of the blastocyst eventually developing into a baby

Placenta

Structure of exchanging nutrients and wasts between mom and baby

Period of the Embryo

The period of the embryo (weeks 3–8) begins when the blastocyst is fully attached to the uterus. During this stage, the body’s major structures and organs begin to develop. The embryo grows and its cells become specialized very quickly. It is protected by the amniotic sac, which contains fluid that cushions it and keeps its temperature stable. The umbilical cord connects the embryo to the placenta and allows oxygen, nutrients, and waste products to be exchanged between the mother and embryo.

3 layers of the embryo

• Outer layer, ectoderm, will become hair and the outer layer of the skin and the NS

• Middle layer, mesoderm, will form muscles, bones and the circulatory system

• Inner layer, endoderm, will form the digestive system and lungs

Period of the Fetus

The fetal period is the final and longest stage of prenatal development, beginning around 9 weeks after conception and lasting until birth. During this stage, the fetus grows larger and its body systems continue to develop and mature. The brain grows rapidly, especially the cerebral cortex, and the reproductive organs develop. The fetus also develops hair, eyebrows, and eyelashes, while vernix forms on the skin to protect it from the amniotic fluid. By around 22–28 weeks, most body systems are developed enough that the fetus may survive if born. This is called the age of viability, although premature babies may have trouble breathing and controlling their body temperature because their lungs and body fat are not fully developed.

Five steps towards a healthy baby

Regular prenatal checkups

Eat healthy food

No alcohol or caffeine; no smoking

Excercise

Get enough rest

Five important general principles about how teratogens usually work

1. The impact of a teratogen depends on the genotype of the organism

2. The impact of a teratogen changes over the course of prenatal development

3. Each teratogen affects a specific aspect(s) of prenatal development 

4. The impact of teratogens depends on the dose

5. Damage from teratogens is not always evident at birth but may appear later in life 

Genetic Counselling

• counsellor constructs a family tree for each prospective parent to check for heritable disorders 

3 stages of labour

• Muscles of the uterus contract, forcing amniotic fluid against the cervix, the opening at the bottom of the uterus that is the entryway to the birth canal 

• When cervix is fully enlarges, the second stage begins 

• Third stage is the placenta expelling from the uterus (afterbirth)

Cephalipelvic disproportion

Infants head is larger than pelvis, making it impossible for the baby to pass through the birth canal

Irregular position

In shoulder presentation, the baby is lying crosswise in the uterus and the shoulder appears first, in breech presentation, the butt appear first

Pre-eclampsia

a pregnant woman has high blood pressure, protein in urine and swelling in her extremities (due to fluid retention)

Prolapsed umbilical cord

The umbilical cord preceded the baby through the birth canal and is squeezed shut, cutting off oxygen to the baby

Caesarean Section (C-Section)

Incision is made in the abdomen to remove the baby from the uterus

Premature babies

Born less than 37 weeks after conception

Small-For-Date (SFD)

A baby that is smaller than expected for how long the pregnancy has lasted.

Apgar score

a measure devised by obstetrical anesthesiologist Virginia Apgar, is used to evaluate a newborn baby's condition

5 vital signs — apgar score

breathing, heartbeat, muscle tone, presence of reflexes, skin tone

Neonatal Behavioural Assessment Scale (NBAS)

• Used within 2 months to provide a detailed portrait of the babies behavioural repertoire

  • Baby's performance is used to evaluate the functioning of 4 systems 

    • Autonomic: ability to control body functions

    • Motor: ability to control body movements and activity level

    • State: ability to maintain a state

    • Social: ability to interact 

Major baby reflexed

• Babinski: a babies toe fans out when the sole of the foot is stroked from heel to toe

• Blink: baby's eyes close in response to bright light or loud noise

• Moro: baby throws its arms out and then inward in response to a loud noise or when its head falls 

• Palmar: a baby grasps an object placed in the palm of its hand 

• Rooting: when a baby's cheek is stroked, it turns its head toward the stoking and opens its mouth

• Stepping: a baby who is held upright by an adult and is then moved forward begins to step rhythmically

• Sucking: baby sucks when an object is placed in its mouth

• Withdrawal: baby withdraws its foot when the sole is pricked with a pin

Alert inactivity

• calm and attentive, eyes open, baby appears to be inspecting environment

Waking activity

• eyes open but seem unfocused, moves arms or legs in bursts of uncoordinated motion

Crying

• cries vigorously, usually accompanied with agitated but uncoordinated motion

Sleeping

• eyes closed, baby drifts back and forth from periods of regular breathing and stillness to periods of irregular breathing and gentle arm and leg motions

Basic cries

• Basic cry – starts softly then gradually becomes more intense and usually occurs when baby is hungry or tired

• Mad cry – more intense version of a basic cry

• Pain cry – sudden, long shriek, followed by long pause and gasping crying 

Growth

The most obvious way to measure growth is by looking at height and weight. It is fastest during the first year, steadier during the preschool years, speeds up again during early adolescence, and then slows down as children reach adulthood. Growth follows two main patterns. Cephalocaudal and proximodistal. Children develop control of large muscle movements before they develop control of smaller movements in their hands and feet. Different parts of the body also grow at different rates.

Cephalocaudal

Heal to tail growth

Proximodistal

Closer to further out growth

Muscle, Fat and Bones

All muscle fibres are present at birth, and muscles become longer and thicker as children grow, especially during adolescence. A layer of fat develops before birth and helps babies regulate their body temperature. Fat increases rapidly during the first year, decreases during the preschool years, and increases again during early elementary school and adolescence. Fat accumulation during adolescence is generally greater in girls. Bones begin forming before birth as cartilage, a soft and flexible tissue. During development, the cartilage gradually changes into bone, starting in the centre and spreading toward the ends.