Psychology of Human Development

Characteristics of Friendships

• Mutual trust becomes important in friendships as individuals grow older
• Characteristics of friendships vary with age, representing discontinuity

Continuity-Discontinuity in Human Development

• Can be viewed in terms of quantitative and qualitative changes
• Quantitative change: a continuous process involving a change in amount
• Qualitative change: a change in characteristic or type, representing discontinuity
• Examples of qualitative changes: puberty, menopause

Study of Human Development

• Considers whether development is a continuous, quantitative process or a discontinuous, qualitative process
• Theories of development differ on whether they view development as stage-based or continuous
• Most theorists agree that age-related changes can be categorized into three types: universal changes, group-specific changes, and individual differences

Universal Changes

• Changes that occur in every individual of a species and are associated with specific ages
• Can be due to biological nature and genetically programmed maturation process
• Examples: infant transitioning from crawling to walking, older adult experiencing skin wrinkles
• Shared experiences, such as a 'social clock', also shape lives into common patterns of change

Group-Specific Changes

• Common to all members of a particular group, with culture being a significant group
• Culture influences individual development and shapes our perceptions of what constitutes normal development
• Examples: retirement-related phenomena in developing nations, where work transitions occur gradually rather than ceasing completely for retirement

Correlations

• A correlation represents a relationship between two variables, expressed as a number between -1.00 and +1.00
• Positive correlation: high scores on one variable typically correspond with high scores on the other
• Negative correlation: a strong inverse relationship where the variables change in opposite directions
• Examples: temperature and air conditioner use, temperature and heater use

Experiments

• A study designed to test a causal hypothesis
• Examples: renowned Canadian longitudinal studies, such as the Concordia Longitudinal Risk Project (CLRP) and the Quebec Longitudinal Study of Child Development (QLSCD)
• Limitations: time-consuming, maintaining contact with subjects over extended periods, participant attrition, practice effects, bias, and cohort issue

Sequential Designs

• A method that can overcome the limitations of both cross-sectional and longitudinal designs

Inheritance of Traits

• Genes causing different shades of brown can combine their effects, resulting in children's eye color phenotypes that differ from those of their brown-eyed parents.
• Many physical traits, such as height, are influenced by both genes and environment (multifactorial inheritance).
• Numerous genes contribute to a child's height and growth rate, but factors like illness, poor nutrition, or emotional neglect can result in a child being smaller than their peers.

Mitochondrial Inheritance

• Mitochondrial genes are only passed from mother to child.
• Mitochondrial inheritance is related to genetic material in the mitochondria of a woman's eggs, not in the nucleus.
• Several serious disorders, including certain types of blindness, are transmitted this way.

Epigenetics

• Epigenomics studies how epigenetic changes, which continually modify DNA markings throughout a person's life, affect gene expression and increase the risk of developing both physical and psychological disorders.
• Acquired epigenetic traits or predispositions can be passed onto subsequent generations.
• Epigenomics is swiftly enhancing our comprehension, diagnosis, and treatment of human diseases and disorders.

Early Intervention

• Evolutionary theory and research are increasing scientists' understanding of the significant impact of early-life events on the susceptibility to chronic diseases and socioeconomic disadvantages in later life.

Research Report

• Type 2 diabetes was uncommon among Indigenous populations before the mid-20th century, but an epidemic seemed to be emerging by the 1970s.

Human Development

Maslow's Hierarchy of Needs

• Maslow proposed a hierarchy of needs, which must be satisfied in a sequential order, starting from the bottom of the pyramid.
• Physiological needs come first, followed by safety needs, love needs, esteem needs, and finally self-actualization needs.

Epigenomics and Personal Growth

• Carl Rogers believed that individuals have the potential and motivation to pursue personal growth and become "fully functioning" without excessive guilt or significant defenses.
• Early experiences with caregivers who conditionally accept a child based on their behavior can undermine the child's self-esteem.

Piaget's Theory

• Piaget proposed that each of us begins life with a small repertoire of sensory and motor schemes, such as looking, tasting, touching, hearing, and reaching.
• He proposed three processes to explain how children get from built-in schemes to complex mental schemes: assimilation, accommodation, and equilibration.

Bandura's Social-Cognitive Theory

• Bandura's early theory underscored the significance of psychological modelling in influencing our thoughts, emotions, and behaviors.
• His later work explored how we exert control over the events that impact our lives.
• Observational learning (modelling) is involved in a broad spectrum of behaviors.
• Learning does not always necessitate reinforcement.

Reciprocal Determinism

• Albert Bandura introduced the concept of reciprocal determinism, a human development process based on the interaction of three factors: personal, behavioral, and environmental.

Conception and Fetal Development

• Conception occurs when a sperm fertilizes an egg cell (ovum) in the fallopian tube, resulting in a zygote with 23 pairs of chromosomes.
• Sperm and ovum each contain 23 single chromosomes, which combine to form 23 pairs in the zygote.
• The 23rd pair, the sex chromosomes, determine the sex of the individual: XX for females and XY for males.

Multiple Births

• Multiple births occur in about 3.1 out of every 100 births in Canada.
• Approximately two-thirds of these multiples are fraternal (dizygotic), originating from two separate sets of eggs and sperm.

Teratogens: Drugs

• Any drug, including antibiotics, can potentially cause birth defects.
• Doctors usually inquire about the possibility of pregnancy in women of childbearing age before prescribing medications.
• Determining the effects of various drugs on prenatal development is complex due to multiple factors, including maternal stress and poverty.

Prescription and Over-the-Counter Drugs

• Thalidomide, a mild tranquilizer, caused serious limb malformations in thousands of exposed fetuses in the 1960s.
• Benzodiazepine tranquilizers and selective serotonin reuptake inhibitors (SSRIs) have been found to have teratogenic effects.
• Pregnant women may need to take certain drugs to manage health conditions, and the benefits of the medication are weighed against potential teratogenic effects.

Tobacco and Smoking

• Infants born to mothers who smoke tend to be about 150 grams lighter, leading to various short- and long-term risks.
• Smoking during pregnancy is associated with higher rates of miscarriage, stillbirth, premature birth, neonatal death, low birth weight, and neurobehavioral disorders.

Alcohol

• Research shows that alcohol can negatively impact prenatal development, affecting an ovum even before ovulation or during its journey to the uterus.
• A zygote can also be affected by alcohol before it implants in the uterine lining.

Maternal Age and Health

• Older mothers (over 35) are more likely to have infants weighing less than 2.5 kilograms at birth, partly due to a higher incidence of multiple births.
• Teenage mothers have higher rates of congenital anomalies, and their infants are more likely to have non-chromosomal congenital anomalies.
• Chronic illnesses like heart disease, diabetes, and epilepsy can negatively impact prenatal development.

Legal Protection for Pregnant Mothers and Fetuses

• Canadian law does not recognize a fetus as a human being and does not classify the termination of a fetus as homicide or infanticide.
• The Canadian Charter of Rights and Freedoms declared everyone's right to life, liberty, and security in 1982.
• The Supreme Court of Canada ruled in 1988 that the abortion law violated Section 7 of the Charter, effectively decriminalizing abortions.

Developing Body Systems and Motor Skills

• The acquisition of motor skills depends on brain development and significant changes in various body systems such as bones, muscles, lungs, and heart.
• Physical development follows two key patterns: the cephalocaudal pattern, which means development progresses from the head downward, and the proximodistal pattern, indicating that development moves from the centre of the body outward.

Bone Development

• During infancy, there are significant changes in the size, number, and composition of bones.
• The growth in the length of long bones in the arms and legs contributes to height increase.
• The number and density of bones in specific body parts change, enhancing coordinated movement.
• Ossification, the process of bone hardening, starts in the final weeks of prenatal development and continues until puberty.
• Ossification plays a significant role in motor development.

Muscle Development

• At birth, the body has all its muscle fibres, but they are small and have a high water-to-muscle ratio.
• Newborns' muscles also contain a significant amount of fat.
• By the age of one, the water content in an infant's muscles equals that of an adult, and the fat-to-muscle ratio starts to decrease.

Gender Differences

• During infancy, girls tend to mature physically faster than boys in some respects.
• Boys are generally more physically active, and differences in physical aggression between boys and girls become apparent towards the end of the second year.

Explaining Motor Skill Development

• The sequence of motor skill development remains virtually identical for all children, including those with significant physical or mental anomalies.
• Motor skill development adheres to the cephalocaudal and proximodistal patterns.
• Experience significantly influences motor development in infants.
• The transition from crawling to walking is driven by several benefits that outweigh the immediate costs.

Preterm Infants

• Infants born before 32 weeks of gestation often lack fully developed adaptive reflexes, making survival tasks like sucking and swallowing difficult.
• Preterm infants are at a higher risk for various health complications, including neurological impairment, cardiovascular disorders, respiratory difficulties, and more.
• Most infants with low birth weight (less than 2.5 kilograms at birth) are preterm, but it's possible for a full-term infant to also be low birth weight.
• Preterm and low birth weight infants typically reach developmental milestones slower than full-term babies due to their younger maturation age.
• Parental responses, particularly from mothers, significantly influence the developmental progress of preterm infants.
• Kangaroo care, which involves holding the newborns for extended periods, has been found to alleviate pain response in premature neonates and promote faster development.

Post-Term Infants

• Infants born after 42 weeks of gestation are classified as post-term.
• Post-term pregnancies carry a higher risk for maternal medical complications and fetal and neonatal mortality.

Infant Mortality in Canada

• In Canada, about half of infant deaths occur in the neonate stage and the rest between 4 weeks and 1 year of age.
• The country's infant mortality rate has significantly declined from 134 per 1000 live births in 1901 to approximately 5 in 2007.
• However, Canada has made less progress in reducing infant deaths compared to 17 peer countries.
• Socioeconomic disparity remains a problem, with lower-income families, those with the lowest education levels, and those experiencing high levels of unemployment and material deprivation having higher rates of infant mortality.
• Infant mortality rates are particularly high among Indigenous populations in Canada.

Depth Perception

• Pictorial (monocular) cues, such as interposition, relative sizes, and linear perspective, require input from only one eye.
• Kinetic cues come from either one's own motion or the motion of an object.
• Binocular cues are used starting at about 4 months of age.
• Linear perspective and other pictorial cues are utilized, possibly between 5 to 7 months of age.

What Babies Look At

• In the first two months, a baby's visual attention is driven by the search for meaningful patterns.
• Babies scan their surroundings until they find a sharp light-dark contrast, typically indicating an object's edge.
• Between 2 and 3 months, babies' attention shifts from the location of an object to its identity.

Imitation and Intermodal Perception

• Infants can't imitate others' facial gestures until substage 4 (8-12 months)
• Imitation requires intermodal perception, combining visual cues from observing another's face and kinesthetic cues from one's own facial movements
• Deferred imitation, where a child imitates an action at a later time, is only possible in substage 6, requiring internal representation

Development in the Real World

• Television viewing is the primary digital activity for families and children up to 14 years old
• Infants are exposed to an average of 5 hours of background television daily, often while playing or eating
• By 24 months, television becomes a regular part of 90% of babies' daily routines
• Extensive TV viewing in early childhood predicts greater viewing in later years

Memory and Cognitive Development

• Infants as young as 3 months can form associations between objects that appear together in their environment
• By 6 months, infants can form new associations with their memories of objects, suggesting that their observations can trigger memories and enable them to combine them in new ways
• Infants' memories are strongly context-dependent, and even slight changes in context can cause 6-month-olds to fail to recognize or remember
• Lost infant memories can be "reactivated" with cues that remind the baby of the association between a behavior and a stimulus

Measuring Intelligence in Infancy

• The Bayley Scales of Infant and Toddler Development is a widely used test that assesses cognitive, language, and motor development

Influences on Language Development

• The interactionist approach emphasizes the role of environmental influences during different stages of language development
• Infant-directed speech (IDS) is a unique way adults and older children communicate with infants, characterized by a higher pitch and repetition with minor variations
• Adults also 'expand' or 'recast' a child's sentences into longer, grammatically correct forms
• Babies display a right-mouth bias when babbling, suggesting that babbling is linked to the beginnings of language production
• Infants develop at least two "tunes" in their babbling, with rising and falling intonations

Word Recognition

• Babies start storing individual words in their memories around 6 months of age
• By 9 or 10 months, most babies understand the meanings of 20 to 30 words
• 14-month-old infants can associate words with objects, but 8-month-old infants can discern fine differences in speech sounds
• Infants are sensitive to subtle differences in speech sounds and are equipped to categorize words into two groups: grammatical and lexical
• Lexical words, which carry significant meaning, are typically longer and have a more complex syllable structure

Mental Health and Attachment

• Mental health issues, such as depression, in caregivers can affect the quality of attachment between the infant and caregiver.
• Mothers with depressive symptoms may struggle to respond to infant signals, such as crying, and may engage in less social touching.
• Infants of mothers with depressive symptoms are at a higher risk of developing insecure attachments and future emotional problems.

Long-Term Consequences of Attachment Quality

• Securely attached children tend to be more sociable, positive towards friends and siblings, less dependent on teachers, less aggressive, and more empathetic and emotionally mature.
• Adolescents who were securely attached in infancy have better social skills, closer friendships, and higher self-esteem.
• Insecurely attached individuals, especially those with avoidant attachments, may have fewer positive friendships and engage in riskier sexual behavior.
• The quality of attachment in infancy predicts sociability and relationship quality in adulthood.

Development in the Real World

• Indigenous Canadians' attachment patterns have been disrupted due to colonization, leading to intergenerational continuity and change in attachment patterns.
• Individuals who have developed a secure attachment can lose it under extreme circumstances, such as colonization.

Temperament

• Negative emotionality/irritability/anger is a tendency to respond with anger, fussiness, loudness, or irritability, and a low frustration threshold.
• Effortful control/task persistence is the ability to stay focused, manage attention, and persist with tasks.
• Temperament differences appear early in life, with both genetic and environmental factors contributing.
• Research suggests that about half of the variation in human temperament can be attributed to 736 specific genes.
• Epigenetic mechanisms, such as prenatal exposure to adversities, can influence neural development and temperament.

Neurological Processes and Long-term Stability

• Temperament theorists suggest that behavioral differences can be traced back to variations in physiological patterns, influenced by heredity.
• Developmentalists argue that the match between children's temperaments and their interpersonal environments influences how inborn temperamental characteristics are manifested.
• Certain aspects of temperament remain stable from infancy through adulthood, such as positive affectivity and disinhibition, which are linked to extroversion and career success.
• Issues with peers, associated with traits like negative emotionality and low sociability, are moderately stable from infancy to childhood.

Self-Concept

• Infants form an internal model of attachment and express their unique temperament while developing an internal model of self.
• The development of self-permanence is crucial for the formation of a sense of self.
• Infants use categorical descriptors like "good" and "big" to describe themselves.

The Emotional Self

• Infants begin recognizing changes in others' facial expressions at 2 to 3 months of age.
• Infants are better at understanding the emotional expressions of familiar faces than unfamiliar ones.
• By 5 to 7 months, infants respond to single-channel information, like facial or vocal expressions alone, even from strangers.
• Infants' understanding of others' emotions helps them anticipate others' actions and guide their own behavior.
• Infants' expression of emotions also progresses, with distinct facial expressions for interest, pain, and disgust, and enjoyment expressions developing quickly.

Emotional Comfort and Attachment

• Emotional comfort is crucial for infant monkeys, often taking precedence over physical needs.
• The ethological perspective suggests that evolution has equipped infants with genes to form emotional bonds with caregivers, known as attachment theory.
• Infants who do not form a close relationship with a caregiver by age 2 are at risk for future social and personality issues.

Adoption and Development

• Adopted children may develop differently due to inherited temperament and personality traits.
• Children adopted before 6 months of age, with no history of institutionalization or abuse, generally show similar attachment security, cognitive development, and social adjustment as non-adopted children.
• Contingent responsiveness in parents fosters secure attachment, while low responsiveness contributes to insecure attachment.

Attachment Security

• Secure attachment is associated with sensitive and responsive parenting.
• Insecure attachment types (avoidant, ambivalent, disorganized/disoriented) are linked to specific parental behaviors and circumstances.

Marital Status

• Infants with married parents are more likely to have secure attachment compared to those with cohabiting or single parents.
• Marital conflict can impact attachment development, and infants as young as 6 months old may show signs of emotional withdrawal.

Interpersonal Milieu

• Shy children may process dopamine and serotonin differently, and have different neurological patterns.
• Temperament and interpersonal interactions can reinforce inherent qualities, and people select experiences based on their temperaments.

The Objective Self

• Around 18-24 months, toddlers develop self-awareness, understanding that they have distinct properties (e.g., gender, size, name, traits).
• Self-awareness is assessed using the mirror test, where the child recognizes themselves and their own reflection.
• As toddlers develop self-awareness, they start to exhibit ownership, identify themselves by name, and recognize their belonging to the "child" category.

Awareness of the Intentions of Others

• Infants develop an understanding that others have separate intentions or "internal mental states".
• Around 1 year, infants expect adults to act beneficially towards others, and by 17 months, they expect adults to help those in need within their group.
• Around 2 years, children understand that others may not always pay attention to what they are focusing on, and they can redirect their attention by pointing.

Infant Cognition and Imitation

• Newborns can imitate facial gestures, such as tongue protrusion, if the model maintains the gesture for a significant period (up to a minute).
• Infants as young as 6 weeks can defer imitation for a few minutes, extending to about 10 minutes by 6 months.
• Babies as young as 9 months can defer their imitation for up to 24 hours, and by 14 months, toddlers can recall and imitate actions up to two days later.

Object Concept and Cognitive Development

• Elizabeth Spelke's research suggests that babies are born with inherent assumptions that guide their interactions with objects, such as the 'connected surface principle'.
• Infants as young as 3 months can form associations between objects that appear together in their environment.
• By 6 months, infants can form new associations with their memories of objects, suggesting that their observations can trigger memories and enable them to combine them in new ways.

Memory and Context

• Infants' memories are strongly context-dependent, and even slight changes in context can cause them to fail to recognize or remember.
• Lost infant memories can be "reactivated" with cues that remind the baby of the association between a behavior and a stimulus.
• Memories become less tied to specific cues or contexts as infants age.

Measuring Intelligence in Infancy

• The Bayley Scales of Infant and Toddler Development is a widely used test that assesses cognitive, language, and motor development.

Language Development

• Nativist theories of language development propose that an innate language processor guides children's comprehension and production of language.
• Infant-Directed Speech (IDS) plays a significant role in language development, helping infants identify specific sounds in their mother's speech.
• IDS also contributes to grammar development, and children are more likely to imitate correct grammatical forms if they hear their sentences recast in that form.

Early Language Experiences

• Children whose parents frequently engage them in conversation, read to them, and use a diverse vocabulary tend to develop language skills earlier and have better outcomes in school.
• Early language experiences, particularly conversational turn-taking interactions between 18 and 24 months of age, are associated with better developmental outcomes in school-aged children.

Indigenous Children and Language Development

• It's crucial to distinguish between language differences and language delays in Indigenous children, who may score lower on language skills assessments due to cultural differences in child-rearing practices.
• Culturally valid, unbiased assessment tools and methods, as well as culturally focused speech-language facilitation and interventions, are important for preparing Indigenous children for school.

Early Milestones of Language Development

• Children, regardless of cultural background, generally follow a similar pattern of language development, including:
  • Crying and making other sounds from birth to about one month.
  • Making laughing and cooing vowel sounds at around 1 or 2 months.
  • Producing consonant sounds and combining them with vowel sounds to form syllables around 6 or 7 months.
  • Babbling and repeating sounds from 6 to 12 months.

Physical Changes

• Babies grow 25-30 cm and triple their body weight in the first year.
• By age 2 for girls and 2½ for boys, toddlers reach about half their adult height.
• 2-year-olds have proportionately larger heads than adults to accommodate their nearly full-sized brains.

The Brain and the Nervous System

• The brain and nervous system undergo rapid development in the first two years.
• At birth, the most developed parts of the brain are the midbrain and the medulla.
• The least developed part at birth is the cortex, which is involved in perception, body movement, thinking, and language.
• The brain doubles in size during the first year.
• Specialized resting-state functional magnetic resonance imaging (rs-fMRI) scans reveal that brain networks become increasingly organized and specialized as connections within and between brain regions strengthen.

Gender Differences

• Girls tend to mature physically faster than boys in some respects.
• Girls' separate bones in the wrist appear earlier, giving them a slight advantage in developing manipulative skills like self-feeding.
• Boys are generally more physically active and tend to prefer rough-and-tumble play from a very early age.
• Differences in physical aggression between boys and girls become apparent towards the end of the second year.

Explaining Motor Skill Development

• The sequence of motor skill development remains virtually identical for all children, including those with significant physical or mental anomalies.
• Motor skill development adheres to the cephalocaudal and proximodistal patterns.
• Research suggests that experience significantly influences motor development in infants.
• The transition from crawling to walking is driven by several benefits, including a broader perspective, faster exploration, and the opportunity for new interactions.

Development in the Real World

• Circumcision is a contentious issue in Canada, with consensus unlikely soon.
• Female circumcision is illegal in Canada, while male circumcision is legal but not medically necessary.
• Both female and male circumcision are deeply rooted practices, often tied to religion, culture, or tradition.

Preterm and Low-Birth-Weight Infants

• In Canada, infants born live before 37 weeks of gestation are classified as preterm.
• The preterm birth rate has remained steady at approximately 8 per 100 live births for the last decade.
• Infants born before 32 weeks of gestation often lack fully developed adaptive reflexes, making survival tasks like sucking and swallowing difficult.
• Preterm infants are at a higher risk for various health complications, including neurological impairment, cardiovascular disorders, and respiratory difficulties.

Perceptual Development

• The development of perceptual skills is best understood as an interaction between innate abilities and experiential factors.
• A child can make visual discriminations between people or objects within the first few days or weeks of life.
• The specific discriminations a child learns and the number of separate objects they recognize depend on their experiences.
• Both innate abilities and experiences contribute to the development of perceptual skills.

The Mother's Experience

• Pregnancy is divided into three trimesters: first (from the first day of the last menstrual period (LMP) to 12 weeks after LMP), second (from 12 weeks after LMP to 24 weeks after LMP), and third (from 25 weeks after LMP to the beginning of labor).
• The first trimester involves a missed period, breast enlargement, and abdominal thickening, with prenatal care involving confirmation of pregnancy, calculation of the due date, and blood and urine tests.
• Serious problems that can occur during the first trimester include ectopic pregnancy, abnormal urine or blood tests, increased blood pressure, malnutrition, bleeding, and miscarriage.

Prenatal Care and Fetal Development

• Prenatal care involves monthly doctor visits to monitor vital functions, uterine growth, weight gain, sugar and protein in urine, and to detect any potential problems.
• The second trimester involves weight gain, "showing," and fetal movements, with prenatal care involving ultrasound to measure fetal growth and locate the placenta.
• Serious problems that can occur during the second trimester include gestational diabetes, excessive weight gain, and Rh incompatibility between the mother and fetus.
• The third trimester involves weight gain, breast discharge, and preparation for labor, with prenatal care involving weekly visits, ultrasound to assess fetal position, and treatment of Rh incompatibility.

Birth and the Neonate

• Birth choices include deciding who will be present during the birth, pain management, and the location of the birth.
• The APGAR score assesses the newborn's condition, with a perfect score of 10 being rare immediately after birth.
• Screening procedures in Canada include detection of rare metabolic disorders in newborns using tandem mass spectrometry technology.
• The Brazelton Neonatal Behavioral Assessment Scale monitors a newborn's development during the first couple of weeks after birth.

Low Birth Weight

• Low birth weight (LBW) is classified as a weight of less than 2500 grams at birth, with a higher incidence of hospitalization, illness, and mortality.
• Most LBW infants are preterm, but it's possible for a baby to be born at term and still be LBW.

Legal and Ethical Issues

• The Supreme Court of Canada ruled in 1997 that a fetus has no legal rights, and a pregnant woman's rights cannot be restricted for the benefit of the fetus.
• The Dobson v. Dobson case involved a pregnant woman who had a car accident, resulting in her child having permanent mental and physical issues, and the court ruled in favor of the boy's compensation.
• The Supreme Court later overturned the ruling, emphasizing the unique relationship between a mother and her fetus, and that the mother's actions cannot be compared to those of a third party when it comes to potential harm to the fetus.

Inheritance Patterns

• Inheritance of curly hair is determined by a dominant gene, but the exact curliness may not match the parent's due to interactions with other genes.
• Blood type is determined by a dominant-recessive inheritance pattern, with type O requiring two recessive genes and types A and B being dominant.

Polygenic and Multifactorial Inheritance

• Polygenic inheritance involves multiple genes contributing to a phenotype, often following a dominant-recessive pattern.
• Skin color is a polygenic trait, with dark skin dominant over light skin, and blending of the two.
• Eye color is also polygenic, with dark colors (black, brown, hazel, and green) dominant over light colors (blue and grey).

Piaget's Theory

• Piaget proposed three processes to explain how children develop from birth to adulthood: assimilation, accommodation, and equilibration.
• Assimilation involves using existing cognitive schemes to interpret new experiences.
• Accommodation involves modifying existing schemes in response to new information.
• Equilibration is the process of achieving a balance between assimilation and accommodation to develop cognitive schemes that align with the environment.

Stages of Development

• Piaget proposed that logical thinking develops in four stages.

Bronfenbrenner's Theory

• Bronfenbrenner's bioecological theory explains development in terms of the relationships among individuals and their environments, or interconnected contexts.
• The microsystem refers to the immediate context, including family, school, and neighbourhood.
• The mesosystem represents the interconnections between these components.

Ecobiodevelopmental Theory

• This theory promotes an interdisciplinary approach to human development, integrating cognitive, emotional, social, and environmental factors.
• It emphasizes the need for a science-based approach toward creating early childhood policies, practices, and interventions aimed at health promotion and disease prevention.

Key Terms

• Accommodation: changing a scheme because of new information.
• Assimilation: the process of using schemes to make sense of events or experiences.
• Behaviourism: the view that defines development in terms of behaviour changes caused by environmental influences.
• Behaviour genetics: the study of the role of heredity in individual differences.
• Behavioural epigenetics: the study of how the environment and personal behaviour can cause epigenetic changes that affect gene expression.
• Bioecological systems theory: Bronfenbrenner's theory that explains development in terms of the relationships among individuals and their environments, or interconnected contexts.
• Chromosomes: strings of genetic material in the nuclei of cells.
• Classical conditioning: learning that results from the association of stimuli.
• Cognitive theories: theories that emphasize mental processes in development, such as logic and memory.
• Defence mechanisms: strategies for reducing anxiety, such as repression, denial, or projection, proposed by Freud.
• Deoxyribonucleic acid (DNA): a chemical material that makes up chromosomes and genes.

Changes in Adulthood

• Life expectancy has significantly increased in developed countries, with a Canadian male born today expected to live beyond 80, and a female past 84.
• The proportion of older adults in the population has grown, with those over 100 being one of the fastest-growing age groups in Canada, expected to increase fivefold to 40,000 by mid-century.
• The lifespan perspective posits that significant changes occur at all stages of development and must be understood within their cultural and contextual framework.
• Paul Baltes, an early pioneer in developing a comprehensive theory of lifespan human development, proposed that the potential for positive change, or plasticity, in response to environmental demands exists throughout life.
• Baltes emphasized the positive aspects of aging, suggesting that as people age, they adopt strategies to maximize gains and compensate for losses.

Domains of Development

• Scientists studying age-related changes typically categorize these changes into three broad domains of development: physical, social, and cognitive.
• The physical domain encompasses changes in body size, shape, and characteristics.
• The social domain encompasses changes in relationships, such as mutual trust becoming important in friendships as individuals grow older.

Continuity-Discontinuity Question

• The continuity-discontinuity question in human development can be viewed in terms of quantitative and qualitative changes.
• Quantitative change involves a change in amount, like children growing taller with age.
• Qualitative change involves a change in characteristic or type, representing discontinuity.
• Examples of qualitative changes include puberty and menopause.

Theories of Development

• Theories of development differ primarily on whether they view development as stage-based or continuous.
• Most theorists and researchers agree that age-related changes can be categorized into three types: universal changes, group-specific changes, and individual differences.

Universal Changes

• Universal changes refer to changes that occur in every individual of a species and are associated with specific ages.
• These changes can be due to our biological nature and the genetically programmed maturation process.
• Examples of universal changes include an infant transitioning from crawling to walking and an older adult experiencing skin wrinkles.

Group-Specific Changes

• Group-specific changes are common to all members of a particular group, with culture being a significant group we all belong to.
• Culture influences individual development and shapes our perceptions of what constitutes normal development.
• Examples of group-specific changes include cultural norms and expectations surrounding retirement.

Research Methods and Designs

• Developmental researchers use the scientific method to achieve four goals: to describe, explain, predict, and influence human development from conception to death.
• Descriptive research involves stating observable changes, such as "Older adults make more memory errors than young and middle-aged adults."
• Explanatory research involves understanding the reasons behind certain events, such as age-related brain changes or experiential factors contributing to memory decline.
• Longitudinal studies, such as the Concordia Longitudinal Risk Project (CLRP) and the Quebec Longitudinal Study of Child Development (QLSCD), are crucial in understanding human development, but have limitations such as participant attrition and bias.
• Sequential designs are a method that can overcome the limitations of both cross-sectional and longitudinal designs.