Chapter 1 Notes
The Scientific Study of Human Development
 Developmental psychology- age-related changes in our bodies, behavior, thinking, emotions, social
interactions, and personalities
o First psychology course taught at Dalhousie in 1838 then St. George’s School for Child Study
o Canadian Psychological Association- wanted to generate solutions to child-care problems in
WW2
o Was part of mental/ moral philosophy
 Philosophical approaches- internal factors or external make a person good or bad
o Philosophical Approaches to Development
 Augustine of Hippo- Original sin- children are sinful and parents must intervene to
correct, Christian belief, nature
 John Locke- The blank slate- children are neutral and parents must shape behavior,
nurture
 John Lock drew upon empiricism: the view that humans possess no innate
tendencies and that all differences among humans are attributable to
experience.
 Jean- Jacques Rousseau- Innate goodness- children are naturally good and parents
must nurture/protect, nature
o Limitations- doesn’t take genetics into account, did not have complete info when theories
were developed
 The field of psychology played a major role in establishing human development
 Physical development- improve muscle control, strength, and coordination
 Cognitive development- strengthen language, numeracy development, imagination, reasoning,
creativity, and problem-solving
 Emotional development- inner thoughts/ feelings, learn persistence and mastery
 Social development- share, co-operate, practice social-cultural value and rules
 Contemporary development
o The term development now encompasses the entire lifespan
o Inborn characteristics interact with environmental factors
o Norms are only 1 measure of change
Early Developmental Scientists
 Darwin
o Can understand development of humans by studying children
o Darwin’s baby biographies were the first organized studies of development
o Critics of baby biographies thought that studying children to prove a theory might result in
misinterpretation
 G. Stanley Hall
o Wanted to find more objective ways to study development
 Used questionnaires and interviews to study large numbers of kids entering schools
 “The Contents of Children’s Minds on Entering School” was the first scientific study
of child development.
o Agreed with Darwin that the childhood milestones were similar to those seen in the
development of humans.
 Wanted to identify norms, or average ages at which milestones are reached
 Arnold Gesell
o Used the term maturation to explain gradual sequential changes
 Suggested the existence of a genetically programmed sequential pattern of change.
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Believed that maturation occurred regardless of practice/ training/ effort
Pioneered the use of cameras and one-way observation to study behaviour
Findings were used to create norm-referenced tests- standardized tests
 Used today to see whether individual children are developing at the same rate as
others
Jean Piaget
o Studied logical thinking in children
 Studies showed that logical thinking develops in four stages between birth and
adolescence.
o 4 stages of development
 Infants explore the world using senses and motor abilities to develop concept of
time/ space
 Develop ability to use symbols (primarily words) to think and communicate
 Then develop skills for logical thinking to solve problems (around age 6 or 7)
 In the teenage years, can apply logic to both abstract and hypothetical problems
o These stages became the foundation of modern cognitive-developmental psychology.
Development in the real world
 Play is critical to children’s development
 Create toys to promote development
o Physical development- improve muscle control, strength, and coordination
o Cognitive development- strengthen language, numeracy development, foster imagination,
reasoning, creativity, and problem-solving
o Emotional development- inner thoughts/ feelings, learn persistence and mastery
o Social development- share, co-operate, practice social-cultural value and rules
 Canadian toy testing council ensures toys are age-appropriate, safe, appealing, useful, challenging
and stimulating for a given age
Brief History of the Roots of Developmental Psychology in Canada
 First psychology course taught at Dalhousie in 1838
o In the beginnings, psychology was seen as part of mental/ moral philosophy
 In 1889 modern scientific psychology came to Canada
 By 1920 funding became available for child-related and family research and in 1925 William Blatz
opened the St. George’s School for Child Study
o Blatz is regarded as the founder and leader of child study in Canada
 Canadian Psychological Association:
o CPA was created in 1939 as a result of psychologists deliberating how they could provide
their services for war effort.
o In Britain, they focused on personnel selection, recruitment and training methods, morale
issues, and aspects of public opinion.
o During WW2, children were evacuated from urban centers
 Canadian psychologists wanted to generate solutions to child-care problems in
WW2
The Lifespan Perspective
 The Lifespan Perspective is the idea that changes occur during every period of development and can
be interpreted by culture and context
 It was once thought that adulthood was a long period of stability followed by a short span of
unstable years immediately preceding to death
o However, adults go through major life changes resulting in stage models of development
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Interdisciplinary approach
o Paul Baltes
 Proposed plasticity or the capacity for positive change in response to the
environmental demands.
 Emphasis on positive aspects of advanced age- strategies to maximize gains/
compensate for losses
Periods of Development
 Prenatal Stage
o Begins at conception and ends at birth
 Infancy Stage
o Begins at birth and ends when the children begin to use language to communicate
o Typically, the first two years of life
 Early Childhood
o The use of language to communicate marks the beginning of Early Childhood.
o Age of the milestone achieved varies across children, but typically this term refers to
children aged 2-6.
 Middle Childhood
o A social event – the child’s entrance to school or another form of social training – marks the
transition from early childhood to middle childhood.
o Varies culturally but typically encompasses children between age 6 and puberty.
 Adolescence
o Typically thought of as beginning at puberty and ending at age 18 but the timing of the
transition varies across individuals.
o Tough to define when adolescence ends because legal adulthood is defined differently for
different activities
 Emerging Adulthood is being proposed as the period to encompass the late teens
and the early 20s.
 Early Adulthood
o Beginning is marked by the attainment of physical maturity and the social norms of each
culture.
 Individuals between the ages of 18 and 40.
o Early Adulthood socially is the period where individuals begin to work towards attaining
independence.
 Middle Adulthood
o Transition begins around age 40 and ends around age 60.
 Late Adulthood
o Commonly known as beginning at age 60, but is not distinguished by any biological or social
events
The Domains of Development
 Physical Domain: includes changes in size, shape, and characteristics of the body (puberty)
o Also included in this domain are changes in individuals’ sense and perceive the physical
world (development of depth perception)
 Cognitive Domain: changes in thinking, memory, problem-solving, and other intellectual skills.
 Social Domain: includes changes in variables associated with the relationship of an individual to
others (ex. studies of children’s social skills)
Developmental Changes in terms of Continuity and Discontinuity
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Whether age-related change is primarily a matter of amount or degree (continuity) or of changes in
type of kind (discontinuity).
o Amount or degree  continuity/ quantitative (change in amount)
 Example: Height (increases with age, but the variable stays the same)
o Type or kind  discontinuity/ qualitative (change in characteristic, kind, or type)
 Example: puberty (before puberty can’t reproduce and after they can)
If development is quantitative then there are no stages (distinct periods) of development
If development includes reorganizations or acquisition of new skills, then qualitative
Age-related changes (Three Categories)
o Universal Changes: common to every individual in a species and linked to specific ages like
shifts from crawling to walking
 Some changes are universal because of shared experiences
 Social clock- set of age norms defines normal life experiences
 Age norms can lead to ageism
 Ageism: a prejudicial attitude toward older adults, analogous to sexism and
racism.
o Group-Specific Changes: shared by individuals who grew up together in a group
 Culture = system of meanings and customs
 Culture shapes development of individuals/ ideas of what normal
development is.
 Cohort = group of individuals born in a narrow span of years and share historical
experiences at the same time in their lives
o Individual differences: changes resulting from unshared events (genetic differences and
hereditary/environmental differences)
 Critical period: specific periods when an organism is sensitive to presence (or
absence) of experience
 Sensitive periods: span of months or years where a child may be responsive to
specific forms of experience or their absence
 On time events occurring at an appropriate time have fewer difficulties than off
time events
 Atypical development: deviation from normal developmental pathway
The Interactionist Model of Development
 Considers development to be the result of complex reciprocal interactions between personal and
environmental factors
 Nature vs nurture interact
 Vulnerability and resilience
o Each child is born with certain vulnerabilities (emotional irritability, alcoholism, or an allergy)
o Each child is also born with protective factors (high intelligence, physical coordination, or a
lovely smile)
 These vulnerabilities and protective factors interact with the child’s environment
o Thus, the same environment can have different effects depending on the qualities of a child
 Highly vulnerable children and an adverse/disadvantaged environment have the more negative
outcomes
 These negative conditions alone can individually be overcome
o A vulnerable child may do quite well in a supportive environment
Research Design and Methods
 Goal of the scientific method is to describe, explain, predict, and influence development
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Describe= state what happens
Explain= why an event occurs
Predict= useful theories produce predictions, or hypotheses that researchers can test
Influence= we can use tests and then provide useful feedback on these tests
Descriptive Methods
 Case studies
o In depth examinations of single person
o Don’t know if findings apply to others
 Naturalistic observation
o Observe people in their environments
o Can have observer bias- ignore behavior that goes against your point of view
 Often use blind observers who don’t know what the research is about
o Time consuming, cannot be generalized
 Survey
o Use interviews and/or questionnaires to collect data/ gather info quickly
 Can combine case study/ survey, case study/ natural observation, survey/ natural observation
Correlations
 Relationship between 2 variables expressed as a number ranging from -100 and +100
o Positive Correlation: as one goes up so does the other
o Negative Correlation: as one goes up the other goes down
o Zero: no relationship between those variables
 Limitation: do not indicate causal relationships
Experiments
 Studies that test a causal hypothesis
 Key feature of experiments is that participants are randomly assigned to groups
 Experimental group receives treatment
 Control group does not or receives neutral treatment
 Independent variable: causal element
 Dependent variable: affected by independent
 Limitations:
o Ethics: Many of the question researchers want to answer are unethical
o Random Assignment: The independent variable that developmentalists are interested is
commonly age, and we cannot randomly assign participants into age groups.
 Solution is Quasi-Experiments
 Quasi-experiments
o Compare groups without assigning the participants randomly
o Cross-sectional studies are an example
Studying Age Related Changes
 Cross-sectional design
o Description: Participants of different ages studied at one time
o Advantages: Quick access to data about age differences
o Limitations: Ignores individual differences and cohort effects
 Cannot tell us anything about sequences of change with age or about the
consistency of individual behaviour over time (each participant tested only once)
 Longitudinal design
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Description: Participants in one group studies several times (solves issue in cross-sectional
designs)
o Pros: Track changes in individuals and groups
o Cons: Time consuming, findings may apply only to the group studies
Sequential design
o Description: Combines the previous 2
o Pros: Both types relevant to same hypothesis
 Allows for the comparison of cohorts
o Cons: Time consuming, different attrition rates across groups
Cross-Cultural Research
 Ethnography- description of a single culture or context based on observation
o Usually, the observer undergoes several years of cultural immersion
 Alternatively, we may test two or more cultures directly by testing the children or adults with
comparable measures
 Canada in 1971 was the first to make multiculturalism an official policy; the Canadian Multicultural
Act was passed in 1988
 Cross Cultural Research is important because:
o Want to identify universal changes
o Helps produce findings that can be used to improve people’s lives
 Cross-Cultural research helps identify specific variables that explain cultural differences.
Research Ethics
 Guidelines to protect the rights of people and animals used in research
o Published by the CPA based on respect for dignity, responsible caring, integrity in
relationships, and responsibility to society
 Protection from harm
o It is unethical to do research that may cause participants permanent physical or
psychological harm.
o If temporary harm exists, need to provide some way of repairing the damage.
 Informed consent
o For anyone over the age of 7
 Confidentiality
o No info is associated with a person so they cannot be identified
 Knowledge of Results
o Summary of results can be provided to participants if requested
 Deception
o Deception may be necessary (placebo drug) but cannot cause distress and participants must
be told about deception once the study is over
Chapter 2 Notes
Genetics
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Cells contain 23 pairs of chromosomes that are made of up of almost 2 meters of deoxyribonucleic
acid (DNA)
DNA
o Double helix made up of Adenine, Thymine, Cytosine, and Guanine
o DNA is found around histones to form nucleosomes (beads on a string)
o On the nucleosomes, there are epigenetic markers that make up the epigenome
o Epigenetic markers control gene expression by either opening or tightening nucleosomes
(chromatin)
 When chromatin open = genes are transcribed and translated
Each chromosome contains segments called genes (that control a specific characteristic)
A gene controlling a specific characteristic always appears in the same place/locus on the same
chromosome
Genome- all the DNA an organism has
o Each body cell nucleus has 20 000 protein-coding genes that tell the body to combine 20
amino acids to build proteins the body needs
Genotype, Phenotype, and Patterns of Inheritance
 Genotype- actual DNA that determines the unique genetic blueprint
 Phenotype- whole set of observable traits
 Dominant-recessive pattern: a single dominant gene influences phenotype (ex. blood type)
o Homozygous- people with 2 recessive or 2 dominant traits
o Heterozygous- one dominant and one recessive
o Dominant traits are seen unless a person has 2 recessive genes
 Dominant and recessive genes differ in expressivity
o This means that the degree to which any gene influences phenotypes varies from person to
person
 Polygenic inheritance: multiple genes influence phenotype (ex. skin color)
o Other examples include eye colour
 Multifactorial inheritance: influenced by genes and environment (ex. Height)
o Other examples include neurodevelopmental disorders.
 Mitochondrial inheritance:
o Genetic material found in the mitochondria of a woman’s eggs
o Passed from mother to child only
 In some cases, serious disorders are passed on to the child this way
 Main idea- emphasize genetic origins
 Strength- medicine and biotechnology
 Weakness- ethical issues
Epigenetics
 Epigenome: molecular biological compounds that overlay our DNA
 Epigenetic markers: signal some genes to turn on (gene expression) or turn off (gene silencing)
o Signal a gene or polygene to make a protein or stop making a protein to regulate normal
bodily functions like blood sugar levels, immune functions, or controlling brain activity
 Epigenetic factors affect development across the lifespan
o Maternal care can physically alter the molecular epigenome
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It has been found that some epigenetic modifications can be passed on
Behavioral epigenetics
o The study of the epigenetic changes related to the development of the brain, behavior, and
psychological processes in relation to environmental factors
o Main areas of research: parenting style and cognition (learning and memory)
Video
o Separate rats to high and low licking
o Mother that takes care of the rats effects the outcome not the mother who gave them the
genes
o Stress of a pregnant mother affects behavior of the fetus
Main idea- environment and life experiences have immediate and long-term influences
Strength- helps understand inheritance factors involved in vulnerability and resilience
Weakness- precise underlying mechanism is unknown
Evolutionary Theories
 Ethology: emphasizes genetically determined survival behaviours that are assumed to have evolved
through natural selection.
 Behaviour Genetics: focuses on the effect of hereditary on individual differences
 Evolutionary Psychology: an approach to explain human behaviour that involves all branches of
psychology and life sciences
o Specifically looks at how genetically inherited cognitive and social traits have evolved
through natural selection
Evolutionary Developmental Psychology
 The mind is not a blank state
 Evolutionary developmental psychology theorists agree that nature (genes) and nurture
(environment) interact in determining individual intelligence, personality, and social behavior
o Need to display different behavior at different points in life (adult vs. child behaviours)
o Age-dependent traits promote survival and adaptation
 Predictive-adaptive responses: epigenetic changes the fetus undergoes to ensure survival in the
anticipated future environment
o The prenate (fetus) picks up cues about existing environmental conditions from its mother
and can predict the environment it will live in
 Fetus undergoes epigenetic changes that ensure best chance for survival in the
anticipated future environment
o Predictive-adaptive responses are only adaptive if the forecast is correct
 Developmentally disruptive: response goes beyond the ability to adapt
 Main idea- changes over generations by favouring traits that help survive and reproduce
 Strength- focuses on the importance of early- life influences on health outcomes
 Weakness- underestimates environment and too much emphasis on heredity
Appling Biological and Evolutionary Theories
 Disease control
o Human genomics can help prevent and predict diseases
o Will help to treat multifactorial diseases like heart disease and cancer
 Human Epigenomics
o Looks at how changes alter gene expression, which can increase risk of physical and
psychological disorders
 Main idea- bio/ physiological processes
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Strength- genetics and epigenetics
Weakness- neglect impact of psych/ sociocultural factors and family conditions
Research Report
 Type 2 diabetes was rare among indigenous populations in the 20th century
 Now it is three times as prevalent and 20% of First Nations live with the disease
o Type 2 diabetes is the leading cause of death and disability among First Nations
 Discovered that a specific genetic mutation (affects liver protein) made a certain population (OjiCree) more susceptible to develop type 2 diabetes.
 Type 2 diabetes epidemic suggests that a genetic susceptibility interacts with multiple environmental
factors
o Transition from low carb to high card diets and increased sedentary lifestyles
Psychoanalytic Theories
 Sigmund Freud
 These theories believe that developmental changes happen because internal drives and emotions
influence behavior
 Libido- internal drive for physical pleasure
o Freud believed libido to be the motivating force behind most behaviour
 Personality has three parts
o Id: contains libido and operates at an unconscious level
 It is the basic sexual and aggressive impulses, present at birth
o Ego: conscious, thinking part of the personality, develops in first 2-3 years
 Job of Ego is to keep the id happy
 Responsible for keeping the three components of personality in balance
o Superego: acts as a moral judge, contains rules of society, develops at end of childhood (6),
 Once developed the ego must make the id happy without violating the rules of the
superego
 Defence mechanisms: ways of thinking about a situation that reduces anxiety, without this tension
would be intolerable
 Really messes with the original sin theory
 5 psychosexual stages
o Oral stage- infant, mouth focused
o Anal stage- libido focused on anus
o Phallic stage- libido focused on genitals
o Latency stage- after a period of dormancy
o Genital stage
 Fixation: behaviors that reflect unresolved problems and unmet needs
 Main idea- 5 stages of personality from birth to adolescence
 Strength- emphasizes infancy and early childhood, psychological explanations for mental illnesses
 Weakness- overemphasizes sexual feelings in development
Erikson’s Psychosocial Theory
 Development was continuous
 In Erikson’s view, to achieve a healthy personality, an individual must successfully resolve a
psychosocial crisis
o Successful resolution of a crisis results in the development of the characteristic on the
positive side of the dichotomy
 8 psychosocial crises to resolve
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Trust vs mistrust: birth to 1 year, depends on reliability of care and affection received at
birth, child gains hope
o Autonomy vs shame and doubt: 1 to 3 years children express independence and self-care
skills, child develops will
 Caregivers must encourage children to function independently with regards to selfcare skills
o Initiative vs guilt- 3 to 6 years develop sense of social initiative and purpose
o Industry vs inferiority- 6 to 12 years, focus on acquiring culturally valued skills, child
develops competence
o Identity vs role confusion- 12 to 18 years, teens must examine identity and roles to achieve
and integrated sense of self, child develops fidelity (a unified and consistent sense of self)
 There is risk that the adolescent will suffer from confusion arising from the
profusion of roles opening up to him
o Intimacy vs isolation- 18 to 30 years, capacity for intimacy is dependent on positive
resolution of identity crisis, develops sense of love
o Generativity vs stagnation- 30 years to adulthood, primary concern is establishing and
guiding the next generation, develop sense of care
o Integrity vs despair- late adulthood, goals is acceptance of life in preparation for facing
death, develops wisdom
Main idea- eight life crises
Strength-helps explain the role of culture in personality development
Weakness- describing each period as a crisis is an oversimplification
Humanistic Theory
 Humanistic theories are based on the premises of the theory of innate goodness
o Most important internal drive is each individual’s motivation to achieve his or her full
potential
 Main idea- emphasis on the basic goodness of human beings
 Strength- focus of development to individual choices
 Weakness- concepts difficult to test empirically
 Abraham Maslow: use the term self- actualization- fulfilling your unique potential
o Was interested in the development of motives/needs
o Two types of motives:
 Deficiency motives: drive to maintain physical or emotional homeostasis (inner
balance)
 Physiological/ safety/ love/ belongingness/ esteem needs
 Being motives: desire to understand, give to other, and grow, to achieve selfactualization
o Main idea- ultimate goal in life is to achieve self-actualization
o Strength- focuses attention on healthy development
o Weakness- terms and ranking are unproven
 Maslow’s Hierarchy of Needs:
o Various needs must be met in order (bottom up)
 Example: only when physiological needs are met do satisfy needs come to the fore;
only when love and esteem needs are met can the need for self-actualization
become dominant
o Being motives only significant in adulthood
 Carl Rogers: personal growth
o Ability to become a fully functioning person without undue guilt or distorting defences
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Can overcome early conditioning or unresolved dilemmas – process known as personal
growth
Main idea- individual’s responsibility for personal growth
Strength- individual can effect change towards growth
Weakness- discounts importance of past events
Learning Theories
 Learning theories assert that development results from an accumulation of experiences
o Based on John Locke’s philosophy
 Behaviorism views development in terms of behavior changes caused by environmental influences –
a process called conditioning
 Main idea- behaviour determined by the environment through conditioning
 Strength- theories can explain consistency and changes in behaviour
 Weakness- approach not developmental; doesn’t tell us much about change over the lifespan
 Pavlov’s classical conditioning
o Unconditioned unlearned natural stimulus eventually becomes conditioned learned stimulus
that elicits the same response every time
 Example:
 Salivation happens when we put food in our mouth
o Food = unconditioned (unlearned) stimulus
o Salivating = unconditioned (unlearned response)
 Stimuli presented just before the unconditioned stimulus are those
associated with it
o Food odours will become conditioned (learned) stimuli to elicit
salivation (conditioned response)
o Unconditioned unlearned natural response
o Classical conditioning plays a role in the acquisition of emotional responses
 Ex. parents are around when a kid is happy, kid feels happy around parent, presence
of a parent comforts the child
o Main idea- learning happens when neutral stimuli are associated with natural stimuli and
elicit a consistent response
o Strength- useful in explaining emotional response/ phobia explanation
o Weakness- explanation is too limited
 Skinner’s operant conditioning
o Operant conditioning involves learning to repeat or stop behaviours because of the
consequences they bring about
 Reinforcement: consequence that follows behaviour increases the likelihood of
repeating behaviour
 Punishment: consequence decreases the likelihood of repeating behaviour
o Positive reinforcement- add a consequence (something pleasant) to increase the chance of
the behaviour occurring again
o Negative reinforcement- take away a condition (something unpleasant)
 Example: taking cough syrup to get rid of cough
o Negative punishment- take away something good to stop behaviour
 Type of extinction: gradual elimination of a behaviour through nonreinforcement
o Positive punishment- add something bad (scolding)
o Partial reinforcement- reinforce a behavior sometimes but not all the time, takes longer to
learn a new behavior but these new behaviors are resistant to extinction
o Shaping- reinforcement of intermediate steps until a complex behavior is learned
o Main idea- behaviour shaped by reinforcement and punishment, people are passive
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Strength- useful strategies for behavior change
Weakness- theory ignores hereditary, cognitive, emotional, and social factors in
development
Cognitive Theories
 Cognitive theories emphasize mental aspects of development, such as logic and memory.
 Main idea- behaviour explained by how the mind operates (memory, thinking, problem-solving)
 Strength- lab experiments
 Weakness- artificial lab tests, can’t always apply to real world
 Jean Piaget: Cognitive-Developmental Theory
o All children go through the same sequences of discovery, making the same mistakes
o Schemes- internal cognitive structures provide an individual with a procedure to follow in a
specific circumstance
 Everyone has a small repertoire of sensory and motor schemes that become
adapted to the world when used
o Assimilation: process of using schemes to make sense of events or experiences
o Accommodation: changing the scheme due to new information acquired through
assimilation
 Process of accommodation is the key to developmental change because through
accommodation, we improve our skills and reorganize our ways of thinking
o Equilibration: balancing assimilation and accommodation to create schemes that fit the
environment
o Logical thinking evolves in four stages
 Sensorimotor: birth to 18 months, infants use sensory and motor schemes to act on
the world
 Preoperational: 18 months to 6 years, acquire symbolic schemes such as language
that they use in thinking and communicating
 Concrete operational stage- 6 to 12 years, think logically and capable of solving
problems
 Acquire conservation: the understanding that a change in appearance
doesn’t necessarily mean that a substance has changed in quantity
 Formal operational- 12 years and older, think logically about abstract ideas and
hypothetical situations
o Main idea- reasoning develops in 4 universal stages to build schemes
o Strength- explains how children of different ages think and act
o Weakness- inexact about some ages, may cause adults to underestimate child reasoning
 Information- processing theory
o The goal of information-processing theory is to explain how the mind manages information
o Focus on types of information:
 Input: info coming in
 Throughput: info transformed by mental programs
 Output: info used to perform actions
o Memory is broken down into subprocesses of encoding, storage, and retrieval
 Encoding: info is organized to be stored in memory
 Storage- keeping info
 Retrieval- getting info out of memory
o Memory Components
 We hear the word when it enters sensory memory
 Next the word moves into short term memory (STM), component where all info is
processed
 Also known as working memory
Knowledge of the words meaning s called out of long-term memory (LTM),
component where info is permanently stored.
o Short term memory: limited capacity, 7 items at a time
o Long term memory- unlimited capacity
o Main idea- cognitive functioning changes with brain maturation
o Strength- explains how different ages manage and process info
o Weakness- human information processing is more complex than this
Juan Pascual-Leone: Neo-Piagetian theory
o Connected info-processing and Piaget
o Older children and adults can solve complex problems because they can hold more pieces of
info in their STM than younger children can
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Sociocultural Theory
 Lev Vygotsky’s Sociocultural Theory
o This theory asserts that complex forms of thinking have origins in social interactions rather
than private learning
o Scaffolding: learning of new skills is guided by someone with more knowledge, adult must
gain and keep attention, model the best strategy, and adapt to the child’s zone of proximal
development (tasks that are too difficult to do alone but can be done with help)
o Main idea- cognitive development is strengthened through social interactions
o Strength- importance of sociocultural interaction
o Weakness- verbal instructions may not benefit cognitive development in some cultures
 Albert Bandura’s Socio-Cognitive Theory
o Observational learning, or modelling
 Watching someone else perform some action and experience reinforcement or
punishment
o Phobias can be learned vicariously
o What a child learns by observing others is influenced by attention and memory
o Reciprocal determinism:
 A process of human development based on personal, behavioral and environmental
factors
 We are affected by our circumstances but can exert influence over our situation,
which in turn affects our expectations about how much influence we have over
future events (coevolution)
o Self-efficacy:
 The belief in one’s own capacity to cause an intended event to occur
 People with a stronger sense of self- efficacy have higher expectations for success
and will put forth more effort and persistence
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Main idea- people learn from models and their interpretation
Strength- explain influence of models, integrates cognitive, emotional, social, environmental
Weakness- does not provide an overall picture, ignores biology
Systems Theory
 Considers the dynamic interactions between personal (biophysical, spiritual, intellectual) and
external factors (physical environment and social and cultural influences)
 Holism: whole is primary/ greater than the sum of its parts
 A person develops in relation to changes in any part of the whole dynamic system
o Growth is a reorganization of the system as it adjusts to change
 When adjustment is adaptive it promotes wellness, when maladaptive= dysfunction or disorder
 Main idea- human and environment active together in the developmental process
 Strength- captures the complexity of individual and contextual variables and their interactions
 Weakness- hard to generalize and predict
Bronfenbrenner’s Bioecological Systems Theory
 Explains development based on relationships between people and their environment or
interconnected contexts, over the passage of time (chronosystem)
o Macrosystem: outermost sphere; manifestation of the overarching sociocultural ideologies,
values, beliefs, and organization of the social systems and public policy
 Macrosystem= Socio-Cultural Context
o Exosystem: socioeconomic context, institutions of the culture that affect development
indirectly
 Ex. The social services, health care, and education.
o Microsystem: immediate context; includes direct variable like families, schools, religion, and
neighbourhoods
o Mesosystem: interconnections within the microsystem
o The person: genetic makeup and developmental stage (individual context) also influences
development
 Main idea- development is a product of individual and contextual variables interacting over time
 Strength- highlights need for research examining interactions
 Weakness- underplays physical environmental influences (pollution, nutrition, disease)
Ecobiodevelopmental Theory
 Jack P. Shonkoff and the American Academy of Pediatrics (AAP)
 Framework for designing, testing, and refining early childhood interventions aimed at health
promotion and disease prevention
o The EBD framework is informed by evidence that indicates the foundations of healthy
development, and the origins of many impairments and susceptibilities to diseases can be
biologically embedded through epigenetic-environment interactions.
 The most cost-effective way to bring improvements in health is to intervene prior to and during the
prenatal and early childhood periods of development
o Formation and implementation of policies and strategies that reduce the disruptive effects
of prolonged and intense adversity in early childhood (toxic stress)
 Main idea- science-based approach towards creating policies aimed at health promotion and disease
prevention
 Strength- promotes advocacy across socioeconomic and political spectrums (health care
professionals take the lead role)
 Weakness- methodological and ethical problems in determining causal links
Chapter 3 Notes
Conception
 One ovum/egg cell per month is released from ovaries, if unfertilized it travels down the fallopian
tubes to the uterus where is disintegrates and is expelled as part of the menstrua fluid
 Every cell in the human body contains 23 pairs of chromosomes
o Sperm and ovum are called gametes with 23 single unpaired chromosomes
 At conception these (ovum + sperm) combine to form a zygote (23 pairs of chromosomes)
o 22 pairs of the chromosomes are autosomes that contain genetic info
 The 23rd pair is the sex chromosomes (determines the sex)
o The x is one of the largest with a lot of genes, but the y is small with a few genes
o 2 x= female
o 1 x 1 y= males
o Meaning sex is determined by the sperm
Multiple Births
 3.1 in 100 births in Canada more than one baby is born (usually twins)
o 2/3 are fraternal twins – come from 2 sets of ova and sperm – also known as dizygotic twins
 1/3 are identical twins – monozygotic – one zygote separates into 2 parts with identical genes
 The annual number of multiple births has increased by 1/3 in the past 3 decades due to the increase
in women over 35 giving birth for the first time
o For unknown reasons it is more likely for older women to have multiple births
o May rely on assisted human reproduction procedures (ovulation stimulation drugs)
 Research Report
o If identical twins (whose genes are the same) who are raised apart are more similar than
fraternal twins (similar but not identical genes) who are raised together, heredity must play
a role in the trait being studied.
o Intelligence Test Scores
 Identical twins reared together > Identical twins reared apart > fraternal twins
reared together > fraternal twins reared apart
 Intelligence test scores are more strongly correlated in identical twins than
fraternal twins; this shows evidence for HERITABILITY of intelligence.
o Difference in attitudes in fraternal twins could be attributed to genetic factors
o There are strong genetic components in both intelligence and attitudes
 Environment (epigenetics) may be even more important
Assisted human reproduction (AHR)
 Regulated in Canada by bill C-6 (Assisted Human Reproduction Act)
 Fertility drugs (hormones that stimulate gamete production)
o Stimulate gamete production
 In-vitro fertilization (IVF)
o Also known as “test-tube baby” method
o Gametes united in a dish and implanted into a uterus
o Typically, they make multiple embryos that are cryopreserved (frozen)
 Newer protocols immerse embryos in cryoprotectants (anti-freeze) and put them in
liquid nitrogen
 This vitrification protocol improves survival rate of embryos when thawing and
implanting
 Lowers the risk of multiple gestations because less embryos need to be implanted
o Older women have lower success with IVF
o
o
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No guarantee that freezing young eggs then using them later will be more successful
Multiple births are more frequent in women who use IVF because doctors transfer several
embryos at once, but multiple embryos put both mom and baby at risk.
o Single embryo transfer (SET) will likely become the IVF norm
 Under 35 you get 2 embryos per cycle
 Over 39 you get 4 embryos per cycle
Artificial insemination
o More successful and less likely to result in multiple births
o Sperm injected into uterus directly
o Often used with men who have a low sperm count or women who want to conceive without
a man
o Carries a risk of infection
Cannot determine genetic heritage when using a sperm donor which is why AHR techniques are
somewhat controversial
Pregnancy and Prenatal Development (gestation)
 Pregnancy is a physical condition in which a woman’s body is nurturing a developing embryo or
fetus.
 Prenatal Development/Gestation is the process that transforms a zygote into a newborn
 The mother’s experience
o 1st trimester
 Zygote implants itself onto the uterus lining (also known as womb)
 Zygote send chemical messages that causes the periods to stop
 Breast enlargement and other physical changes happen
 Cervix thickens and secretes a mucus barrier that protects the developing embryo
 Uterus shifts to put pressure on the bladder- urinate more often
 Fatigue and breast tenderness, may interfere with sleep
 Early symptom is morning sickness
 Prenatal care during the 1st trimester is critical to prevent congenital anomalies (all
organs form during first eight weeks)
 Early prenatal care can identify maternal conditions like STIs
 Cannot drink or do drugs
 Ectopic pregnancy- zygote implants in fallopian tubes
 15% end in miscarriage or spontaneous abortion similar to a period
nd
o 2 trimester
 End of week 12 to week 24
 Increased appetite and morning sickness usually disappear
 Gains weight and the uterus expands to accommodate the growing fetus
 Begin to “show”
 Mother can feel movement between 16th and 18th weeks
 At monthly checkups they monitor mother and baby vitals
 Can determine sex at 13th week via ultrasounds tests
 Urine tests check for gestational diabetes
 A type of diabetes that only happens during pregnancy
 Any type of diabetes poses many risks:
 Baby grows too fast leading to premature labor or a baby too big for vaginal
delivery
 Risk of miscarriage drops in the second trimester but can deliver a premature baby
after the 21st week (may survive)
rd
o 3 trimester
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25 weeks
Mainly characterized y weight gain and abdominal enlargements
Breasts secrete colostrum to prepare for nursing
Begin got feel emotionally connected to fetus
Individual differences in fetal behavior like hiccups or thumb sucking may become
obvious (last weeks of pregnancy)
 Notice that the fetus has regular periods of activity and rest
 Weekly visits at week 32
 Toxemia of pregnancy- sudden increase in blood pressure that can cause a stroke
 Need to monitor blood pressure
Cephalocaudal pattern – development proceeds from the head downward
Proximodistal pattern – development happens from the centre outwards
Milestones in Prenatal development
o Germinal stage
 First 2 weeks from conception to implantation
 Cells specialize
 By day 4 the zygote contains dozens of cells
 Day 5 – cells become a hollow fluid-filled ball called a blastocyst and inside of it cells
clumps together
 Day 6/7 the blastocyst comes into contact with the uterine wall
 Day 12 – blastocyst is buried in the uterine wall (implantation), body cells are
formed
 Some of the blastocyst cells combine with the uterine wall to create the placenta
that provides oxygen and nutrients to the baby
 Brings blood close but it does not mix
 Placenta secreted hormones that stop periods and keep the placenta connected to
the uterus
 The blastocysts inner cells begin to specialize
 One group of cells form the umbilical cord (connects embryo to placenta)
 Other cells form the yolk sac that produces blood cells until the embryo’s
blood-cell producing organs are formed
 Other will cause the Amnion to be formed- fluid-filled sac that the baby
floats in until birth
o Embryonic stage- critical period
 Begins at implantation- 2 weeks after conception until end of week 8
 At week 3 neurons form neural tube – will become spine and brain
 Heart and kidneys develop in week 3, and 3 sacs that will become the digestive
system
 Week 4- neural tube swells to form the brain, eye spots appear, heart begins to
beat, backbone and ribs are visible, bone and muscle cells move into place, face
takes shape, endocrine system develops
 Week 5- 6.5mm long, 5 fingers, eyes have corneas and lenses, lungs begin to
develop
 Week 6- brain produces patterns of electrical activity, gonads develop
 Development of gonads depends upon the presence or absence of androgens
 Androgens (testosterone) cause testes, lack of androgens cause ovaries
 Week 7- move spontaneously, visible skeletons, fully developed limbs, semi-upright
posture, eyelids seal shut, tooth buds in jaw
 Week 8- liver and spleen begin to function, heart is developed, organogenesis
(organ development) is complete
o
 Liver and spleen allow the embryo of make and filter its own blood cells.
Fetal stage
 End of week 8 until birth
 2 grams and 2.5 cm to the end of 38 weeks when a fetus is 3.2 kg and 50 cm
 Week 9-12: fingerprints, grasping reflex, facial expressions, swallowing and rhythmic
breathing or amniotic fluid, urination, genitalia appear, activity and rest
 Week 13-16- hair follicles, responses to mother voice and loud noises, 8-12 cm long
from crown to rump, 25-100 grams
 Week 17-20- Fetal movements felt by mother; heartbeat detectable with
stethoscope; lanugo (hair) covers body; eyes respond to light introduced into the
womb; eyebrows; fingernails; 13 to 17 centimetres long, crown to rump; weighs 140
to 300 grams
 Weeks 21-24- Vernix (oily substance) protects skin; lungs produce surfactant (vital
to respiratory function); viability becomes possible, although most born now do not
survive
 By the end of week 22, 20-33% have viability and can live outside the womb
 By the end of week 23 survival rates go up to 38-58%
 By the end of week 24 survival rates are 58-87%
 Weeks 25-28- Recognition of mother’s voice; regular periods of rest and activity; 35
to 38 centimetres long, crown to heel; weighs 660 to 1000 grams; good chance of
survival
 Weeks 29-32- rapid growth; antibodies acquired from mother; fat deposited under
skin; 39 to 43 centimetres long, weighs 1.2 to 1.7 kilograms; excellent chance of
survival
 Weeks 33-36- Movement to head-down position for birth; lungs mature;
approximately 44 to 48 centimetres long, crown to heel; weighs about 1.9 to 2.6
kilograms; virtually 100% chance of survival if delivered
 Weeks 37+- Full-term status; about 49 centimetres long, crown to heel; weighs 3 kg
The Fetal brain
 Formation/ fine-tuning
 Neural formation speeds up between 10-18th weeks (known as neural proliferation)
 Week 13-21- neurons (cell bodies) migrate to designated part of brain
o While migrating, neurons only consist of cell bodies
o Once they reach their destination, they begin to develop connections called synapses
o Synapses are spaces tiny spaces between neurons across which neural impulses travel from
one neuron to the next via neurotransmitters (chemical messengers)
 Yawning is a sign of normal fetal brain development
 Once they reach their destination synapses form- synapse formation requires growth of axons and
dendrites
 Dendrite development is sensitive to adverse environment (maternal malnutrition)
 Simultaneously with neuronal migration, glial cells develop and hold neurons together
o Now the brain, can be seen on MRI
 4% of babies have a congenital abnormality at birth
Sex Differences
 Sex-determining region Y (SRY) gene on the Y chromosome signals the male embryo’s body to
secrete androgens
 Female embryos exposed to androgens via medications or congenital adrenal hyperplasia can
develop male appearing genitalia
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Androgens affect the developing brain
o Some areas may be larger while others are smaller – some areas of the brain can be more
masculine in males and more feminine in females
o May play a role in the development of sex differences in areas of cognitive functioning,
spatial ability, communication skills, the development of sexual orientation later in life and
also in neuropsychiatric disorders
 Major depressive in girls and autism in boys
Females grow more slowly, male fetuses more responsive to touch, female fetuses responsive to
sound
Females are 1-2 weeks ahead in bone development at birth, however boys are longer and heavier,
thus, girls acquire coordinated movements and motor skills faster
o Gap widens until the teens where boys catch up and surpass girls in physical coordination.
Females have 2 X chromosomes so the other can compensate for defects
Prenatal Behaviour
 Fetuses can tell the difference between familiar and novel stimuli by the 32/33rd weeks
 Newborns can remember stimuli they were exposed to prenatally
o Adapted sucking patterns to listen to a familiar song
o Fetuses had a different heart rate in response to mother’s voice (higher HR) than a stranger
(lower HR)
Genetic disorders
 Autosomal disorders caused by non-sex genes
o Phenylketonuria: recessive gene causes problems digesting phenylalanine, so toxins build
up and cause developmental delays
 Cannot have milk or other foods with phenylalanine, more likely in Caucasian
o Sickle-cell disease: more likely in west African or African American, red blood cell
deformities, cannot carry enough oxygen to keep tissues healthy
 With early diagnosis and antibiotic treatment, 90% of children survive
o Tay-Sachs disease: eastern European Jewish and French Canadians; intellectually delayed
and blind, few live past the age of 3
o Huntington’s disease- not diagnosed until adulthood, brain deteriorates and affects
psychological and motor functions, diagnosed with blood test
o Most disorders caused by recessive genes are diagnosed in infancy and early childhood and
disorders caused by dominant genes are not diagnosed until early adulthood.
 Sex-linked disorders caused by X chromosome recessive genes
o Most sex-linked disorders are caused by recessive genes
o Red-green color blindness
 Difficulty distinguishing between the colours red and green; 7-8% men and 0.5%
females
o Hemophilia: lack chemical components required for blood clotting, 1 in 5000 boys, few girls
 When a person bleeds, the bleeding doesn’t stop naturally
o Fragile-X syndrome: X chromosome has a damage that gets worse with age
 Causes developmental delay and becomes progressively worse with age
Trisomies
 Chromosomal error/chromosomal anomaly: having too many or too few chromosomes
 In trisomies, the child has 3 copies of a specific autosome
 Most common is trisomy 21: down syndrome
o
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Intellectually delayed, distinctive facial features, hypothyroidism, hearing loss, heart
anomalies
o Greater risk for mothers over age 35 for bearing a child with trisomy-21
Also found trisomies in the 13th and 18th chromosomes and these trisomies are more severe than
trisomy-21.
Sex chromosome anomalies
 XXY pattern, Klinefelter’s syndrome
o Affected boys usually look normal but have:
 Underdeveloped testes, low sperm count, language/ learning disabilities,
experience male and female changes during puberty
 Turner’s syndrome XO pattern
o Anatomically female but show stunted growth
o Are at higher risk of heart and kidney malformations
o Without hormone therapy, they do not menstruate or develop breasts at puberty
Teratogens: Maternal Diseases
 Teratogens: agents that cause damage to an embryo or a fetus.
o During the first eight weeks of gestation, this I the period when exposure to teratogens
carries the greatest risk.
 Viral Infections
o Organ systems are most vulnerable when they are developing the fastest
 3-16- CNS
 3- 6- heart
 4-5- arms and legs
 4-9- ears and eyes
 6-8- teeth and palate
 7-9- genitals
o Rubella and German measles can pass through the placental filter to the embryo causing
death, hearing/ visual impairment, heart anomalies
o Mosquito- transmitted Zika Virus (insect borne diseases) can cause adverse birth outcomes
like microcephaly and other neurological disorders, and there’s no effective vaccine
o Cytomegalovirus CMV: in the herpes group and is transmitted through contact with body
fluids
 Can cause deafness, CNS damage, intellectual delay
 As many as 60% of Canadian women carry CMV but have no recognizable symptoms
o HIV/ AIDS: HIV is the virus that causes AIDS
 Crosses placenta into fetal bloodstream
 The virus can be contracted in the birth canal during delivery or can be passed
through breast milk after delivery
 Infected moms can have baby is they have C-section and formula feeding (lowers
risk of transmission)
 Infants become sick within 2 years of birth, weakens immune system, more likely to
get pneumonia or meningitis
 Children with HIV cannot be properly vaccinated with vaccines that use live viruses.
o Syphilis: most harm during last 26 weeks, causes ear/ eye/ brain anomalies
o Genital herpes: passed during birth, causes death in 1/3 and blindness/ brain damage in ¼
o Gonorrhea- passed during birth, causes blindness, eyes must be treated with special
ointment
 Drugs
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Thalidomide- mild tranquilizer for morning sickness caused limb malformations in fetuses
Benzodiazepine- risk of preterm delivery, low birth weight, low agpar score, higher NICU
admissions, and respiratory distress syndrome
o SSRI- preterm delivery if started after first trimester
o Must weigh risk vs reward- need to take anti-seizure meds, heart meds, diabetes, asthma,
and psychiatric drugs
Tobacco
o 150 grams lighter at birth
o Pregnant women who smoke have higher rate of miscarriage, stillborn, preterm, neonatal
death, neurobehavioral disorders
o More common in indigenous mothers
Alcohol
o Fetal Alcohol Syndrome (FAS): these children have smaller brains and bodies, heart
anomalies, hearing loss, distinctive faces (small wide set eyes, flat nose, thin upper lip, flat
space between nose and mouth), mild developmental delays, learning/ behavior difficulties
o Fetal Alcohol Effects (FAE)- milder or partial adverse effects of ethanol
 Children with FAE may not exhibit physical characteristics of FAS, but the secondary
disabilities (mental health problems) become apparent during childhood.
o Fetal Alcohol Spectrum Disorder (FASD)- includes both FAS and FAE
o Should abstain during conception
o Prevalence of FASDs is significantly higher in Indigenous populations
Cannabis
o Studies on marijuana use during pregnancy has yielded mixed results
o Unable to see the effects because of confounding variables (smoking cigarettes, drinking)
o Cannabinoids (THC) affect the mom’s mind and body, so it does the same to the baby
o No concise evidence on the negative effects of cannabis has been found
Psychotropic drugs
o Heroin and methadone: miscarriage, preterm, early death, 60-80% are born addicted, highpitch cries,
 Babies suffer from withdrawal symptoms, irritable, tremors, vomit, convulsions,
sleep problems
o Cocaine: developmental problems, women who use are typically poor and use multiple
substances, disruption of placental function, premature
o Marijuana- mixed results, excreted in breast milk
Diet
o Folic acid (b vitamin) is vital to prenatal development, low amounts can cause spina bifida in
the earliest weeks of pregnancy
o Must prevent malnutrition during final 3 months to prevent a low-birth-weight infant under
2500 g who will have intellectual difficulties in childhood
 Impacts nervous system
 Reduced brain weight and capacity for learning
o Women should gain 11.5-16 kg during pregnancy
Age
o Greater risk of multiple births with age
 Babies are also at risk of weighing less than 2.5 kgs and these babies are at higher
risk of having problems such as heart malformations and chromosomal disorders.
o Higher rates of congenital anomalies in teens
 Neural tube, CNS, GI, female genitalia, MSK, integumental anomalies
 Teen moms less likely to receive adequate prenatal care
 More likely to have mood disorders, STIs, partner abuse
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Chronic illnesses
o New speciality of fetal-maternal medicine is to manage pregnancies in a way that supports
mother with chronic illnesses and the baby
o Erratic blood sugar levels
o Immigrants have fewer problems
Maternal mental health
o Fetuses of stressed mothers more likely to have emotional/ cognitive disorders
o Anxiety and depression change body chemistry in the mom that gets passed to the fetus
o Fetus grows slower when mom is stressed or depressed
Teratogens fall within three broad categories:
o Mutagenic 15-25%
 Mutagens alter genomic DNA
 Radiation/biological toxins can cause germinal mutations interfere with conception
and normal development of embryo and the fetus
 High levels of X-rays can cause failure to implant or miscarriage
 Fetuses may develop somatic mutations- chromosome/ genetic errors that cause
congenital anomalies
o Environmental 10%
 Environmental teratogens have direct, nonheritable effects by damaging/ disrupting
cells
 These agents my interfere with proliferation in the embryo (formation of specific
tissues)
 May interfere with migration (movement of cells to predetermined location)
 Can cause cell structure/ function abnormalities
 The destruction or degeneration of cells
 First Nation woman are subject to transplacental transfer of heavy food sources
(mercury, cadmium, lead) to the fetus.
 Prenatal exposure to pollutants causes preterm birth, low-body-weight,
and small for gestation age infants who are at high risks of morbidity and
other adult diseases (CVD, cancer)
o Epimutagenic 67%
 Epimutagens are agents that cause alterations to the epigenome without changing
the genomic DNA
 Can be shaped by genetic, ecological, and social factors
 Cause alterations to epigenome but do not change genomic DNA
 Alteration present in only one generation as the acquired epimutations resets after
conception
 In some cases, acquired epimutations can be passed on (ex. Diet)
Paternal influences
 Fathers pass on roughly 55 genetic mutations compared to a mother’s 14
o Decreased sperm performance contributes to infertility, decreased fertility, and miscarriage.
o DNA damage to sperm contributes to congenital anomalies, cancer, and neurobehavioral
disorders.
 Genetic effects (gene mutation and chromosomal errors) and epigenetic effects (altered gene
expression) have the greatest impact during the first 2 trimesters of pregnancy
o Contaminating the mother and prenate may involve toxins in seminal fluids that can be
transmitted during intercourse or via indirect exposure
 Male-mediated teratogenic and mutagenic risk is related to paternal exposure to toxic substances
o Sperm adversely affected 2-3 months before conception can impact the prenate
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Preconceptual factors such as poor diet and fitness, obesity, smoking can also impact their offspring
Congenital anomalies have been linked with both teenage fathers and fathers who are in their 40s or
older
o The number of mutations a father will pass on to his child doubles every 16.5 years from the
time the father reaches puberty
o Specifically, older men- children with autism/ schizophrenia
Physical abuse of the mother can lead to preterm, placenta breaking away from uterine wall, LBW
Fetal Assessment and Treatment
 There are medical risks involved with genetic testing for both mother and prenate
 Genetic Non-Discrimination Act (GNA):
o GNA provides legal protection against discrimination based on genetic information
 Ultrasonography
o Monitor fetal growth
 Amniocentesis
o Week 14-16
o Needle extracts amniotic fluid and fetal cells are filtered out to test for chromosomal or
genetic disorders
o Lower risk of miscarriage/ fetal injury
o Amniocentesis is routinely used as a screening tool for Down Syndrome and other
chromosomal disorders in women over 35.
 Chorionic Villus Sampling (CVS)
o Cells are extracted from the placenta and used in tests during the early weeks of prenatal
development
o Used when a medical condition in mother makes in necessary to determine fetal
abnormalities
o Can screen for down syndrome and chromosomal disorders
 Lab tests
o Use maternal blood, urine, and amniotic fluid samples to monitor fetal development
o Presence of alpha-fetoprotein is bad
o Assess maturity of fetal lungs
 Fetoscopy
o Insert camera into womb to monitor development and correct surgically
o Fetoscopy makes it possible for doctors to correct anomalies surgically
o Enables fetal blood transfusion and bone marrow transplants
 Identify bacterial infection that causes slow growth that can be treated by injecting
antibiotics into amniotic fluid or into the umbilical cord.
Birth Choices
 The Location of the Birth
o A traditional hospital maternity unit
o A birth centre or birthing room within a hospital
o A free-standing birth centres
o The mother’s home
 Midwife
o Assess, supervise, care for women prior to and during pregnancy, labour and the
postpartum period
o To become a midwife, it requires midwifery education program
 Drugs
o
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Analgesics reduce pain
Sedatives or tranquilizers reduce anxiety
Anaesthesia blocks pain
 Either totally (general anaesthesia) or certain portions (local anaesthesia, such as an
epidural)
 Mother who has an epidural has less power for pushing, so the birthing process
slows down, and other procedures will be used (vacuum suction)
o All drugs given during labour pass through placenta into fetal bloodstream
 Infant whose mothers received any type of drug are typically more sluggish, can
have trouble suckling (“latching on”), gains less weight, sleeps more
Natural childbirth
o Lamaze method
o Select support labour coach and attends childbirth classes that psychologically prepare the
woman and her labour coach for the experience of labour and delivery.
 For example, learn to use word contraction instead of pain
The physical process of birth
 Stage 1
o Cervix opens up (dilation) and flattens (effacement) to about 10cm
o Early/ latent phase: contractions are spaced out
o Active phase: cervix is 3-4 cm dilated until 8 cm dilated, and the contractions are closer
together and more intense
o Transition phase: last 2 cm of dilation
 Contractions are closely spaced and strong, but this phase is usually the shortest
phase
 At the end of this phase pushing can start and stage 2 begins
 Stage 2 (Delivery)
o Less than an hour usually
o Pushing
 Stage 3
o Afterbirth/ placental delivery
 Caesarean deliveries
o If breech (baby is positioned butt first), fetal distress, long labour process, large fetus,
maternal health conditions, this may be the preferred method
o Even though C-sections are warranted, the procedure itself is controversial
 Concerns about possible increased risk due to complications (blood loss/blood clots)
o Sudden change in BP
 Birth complications
o Fetal distress
 Change in heart rate from pressure on umbilical cord, collapsed blood vessels
cannot carry blood to and from baby so anoxia occurs
o Infants may dislocate shoulders or hips, fractures, temporary paralysis due to facial nerve
compression
 After giving birth, women typically require one month to recover
Assessing the neonate
 First month of life a baby is actually referred to as a neonate
 Heath of the baby is assessed right after birth then 5 min later using Apgar scale
o Measures heart rate, respiratory rate, muscle tone, response to foot stimulation, and color
o Score >7 is great, 4-6 needs help, <3 critical condition
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Tandem mass spectrometry can detect inborn metabolic anomalies pre-symptomatically
Brazelton Neonatal Behavioral Assessment Scale tracks development in first 2 weeks following birth
and looks at responses to stimuli, reflexes, muscle tone, alertness, cuddliness, ability to self soothe
Low Birth Weight (LBW)
 Neonates below 2500 grams are classified as having LBW
 Most LBW infants are usually preterm
o The small-for-date neonates have retarded fetal growth and poorer prognoses than infants
who weigh an appropriate amount for their gestational age.
 LBW infants display low levels of responsiveness
 Those born more than 6 weeks early are more likely to have respiratory distress syndrome (hyaline
membrane disease)
o Poorly developed lungs cause serious breathing difficulties
o Require administration of surfactant
 Any infants below 1500 grams remain smaller than normal and have long term health problems and
neurodevelopmental outcomes (ex. motor and sensory impairments)
 Boys are more likely to show the long-term effects than girls
Law- in 1969 section 287 of the Canadian criminal code made abortions illegal, later got thrown away in 1988
Chapter 4
Physical Changes: The Brain and the Nervous System
 The first two years of life is the period where the greatest degree of physical change occurs
o Grow 25-30 cm and triple their body weight.
o By age 2 (females) and 2 ½ (boys) toddlers will be half as tall as they will be as adults
 The brain and the nervous system rapidly develop during the first two years
o At birth, the midbrain and the medulla are fully developed and are connected to the spinal
cord to regulate vital functions (heartbeat, respiration)
o Cortex is the least developed part of the brain (involved in perception, thinking, language)
 Connectome: a map of all the neural connections
o Human brain doubles in size during the first year.
o Brain networks become hierarchically organized and specialized as connections within and
between brain regions are strengthened.
 Brain networks link via “connector hubs” that facilitate information exchange
Synaptic Development
 Brain structures are composed of neurons and glial cells
 Synapses: connections between neurons
 Synaptogenesis: the creation of synapses
o Happens in spurts (not continuous) and results in the quadrupling of the brain’s weight by 4
 Synaptic Pruning: a period where unnecessary pathways and connection are eliminated
o Follows the period of synaptogenesis
 Infants have denser dendrites than and adult does but less efficient compared to the adult
 Neuroplasticity: the brains ability to change in response to experience
Myelinization
 Myelin: sheaths around axons which insulate them from one another electrically and improves their
conductivity
 Myelinization: the process of developing this sheath
o Myelinization follows both cephalocaudal and proximodistal patters.
 Nerves serving muscles in the neck and shoulder are myelinated before those
serving the abdomen.
o Most rapid during the first two years but continues at a slower pace during childhood and
adolescence.
 Reticular Formation: the part of the brain responsible for keeping your attention on what you’re
doing and helping you sort out important info
o Myelinization for RF begins in infancy and continues into childhood and adolescence
Reflexes
 Adaptive Reflexes: reflexes that help us survive
o The Rooting Reflex: when cheek is touched, head will turn to that side
o Sucking Reflex: newborns automatically start sucking an object that enters the mouth
 Research suggests that stimulation of some reflexes may facilitate later development
o Infants who were encouraged to exercise (stepping reflex) were likely to display stepping
movement and began walking at an earlier age.
 Primitive Reflexes: controlled by the medulla and the midbrain and their purposes are unclear
o The Startle Reflex (Moro): loud noise makes baby throw her arms outwards and arch back
o The Babinski Reflex
o
By 6-8 months primitive reflexes start to disappear
Behavioural States
 States of Consciousness: five different states of sleep and wakefulness in neonates
 Neonates sleep as much as 80% of the time
o By week 8 the total amount of sleep drops and circadian rhythms become evident
o By 6 months babies sleep around 13 hours a day but the sleep is regular and predictable
 Cultural beliefs play an important role in parents’ responses to infants sleep patterns.
 Infants have different cries for pain, anger, or hunger
o The basic cry (hunger): cry, silence, breath, cry, silence, breath
o The anger cry: louder and more intense
o Pain cry: abrupt onset
 Crying increases in frequency over the first 6 weeks and tapers off; parental attention decreases the
frequency of crying
 Colic: a pattern involving intense bouts of crying (3+ hours a day), 3+ times per week for more than 3
weeks for no apparent reason
o Appears around 2-3 weeks and then disappears at about 3-4 months
o No single form of treatment has been found to be universally effective
Developing Body Systems and Motor Skills
 Bones
o During infancy, bones change size, number, and composition
 Increasing length of long bones underlie increases in height
 Changes in bone number and density are responsible for coordinated movements
 Example: development of wrist bones (cartilage  nine separate bones)
o Ossification: the process of bone hardening
 Begins in the last two weeks of prenatal development and continues into puberty
 Muscles
o Body’s full complement of muscle fibers are present at birth, but the fibers are small and
have a high-water content and a high proportion of fat
 By age 1, ratio of fat to muscle starts to decline
 Changes in muscle composition leads to increases in strength that allows 1-year old
to run, jump, climb, etc.
 Lungs and Heart
o Lungs grow rapidly and become more efficient during the first 2 years
Motor Skills
 Locomotor Skills (gross motor skills): include abilities such as crawling that enable the infant to get
around in the environment
 Non-locomotor skills: improve babies’ ability to use their senses and motor skills to interact with the
objects and people around them (ex. Controlling head movement)
 Manipulative skills (fine motor skills): involve the use of the hands
 Development during the first 24 months:
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o
There’s a wide variety in the ages that infants reach developmental milestones.
Gender Differences
 Throughout infancy, girls are ahead of boys in some aspects of physical maturity but typically boys
are more physically active
 Despite the rate of physical development, the sequence of motor skill development is virtually the
same for all children (even those with physical or mental anomalies)
o Developmentally delayed children may be slower, but they go through the same sequence
 Believed that experience influences motor development
Health Promotion and Wellness
 Nutrition
o Breastfeeding is superior to bottle-feeding
 Breastfeeding should be the sole form of infant nutrition for the first 6 months
 Women who have higher SES are likely to initiate and maintain breastfeeding
 Breast milk contributes to rapid weight and size gain
 Breastfed infants are less likely to suffer from diarrhea, ear infections,
bronchitis, and colic and are also less likely to die
 Long term they have lower risks for chronic diseases (diabetes, obesity) and
neurodevelopmental disorders
 The positives may be because breast milk stimulates guy microbiota and immune
system function
o Breastmilk is not sufficient for preterm babies
 Need special formulas containing amino acids and fats (typically mixes these with
breastmilk)
o
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Order of food introduction for babies
 Iron fortified grain cereals, pureed vegetables, fruits, and lastly, meat
Malnutrition
o Macronutrient Malnutrition: a diet that contains too few calories
 The world’s leading cause of death for children under the age of 5
o Marasmus: a disease that occurs when calorie deficit is severe
o Kwashiorkor: disease caused by diets that have enough calories but not enough proteins
o Micronutrient Malnutrition: a deficiency of certain vitamins and/or minerals
 Mortality rates can be reduced by 23% by supplying at risk children with Vit A.
Health Care and Immunizations
o Routine immunization should be commenced at 2 months of age
Illness in the First Two Years
o Over half of infants in Canada have a respiratory illness in the first year of life
 Babies in daycare centres have twice as many as those reared at home
o Keeping a baby too clean may be detrimental (need to expose them to harmless germs)
o Babies with chronic ear infections are likely to have learning disabilities, attention disorders
 Because ear infections impair hearing; may compromise brain development
Preterm and Low-Birth-Weight Infants
 Preterm: infants born live before 37 weeks of gestations
o Preterm babies are at higher risk for neuro impairments, CVD, respiratory and gastro
complications
o Long term, they are likely to experience motor, cognitive, visual, hearing, growth problems
 Infants born before 32 weeks don’t have adaptive reflexes (can’t swallow)
o Need to fed intravenously.
 Preterm and LBW babies move slower from one developmental stage to the next (because they are
maturationally younger than full term baby)
 Kangaroo Care: parents with preterm babies are shown how to increase skin-to-skin contact
o Premature babies who receive kangaroo care develop faster than those that don’t.
Post-Term Infants
 Post-Term: infants born after 42 or more weeks of gestation
o Post term pregnancies are associated with higher risks for maternal medical complications
and with fetal and neonatal mortality
Infant Mortality in Canada
 Half of infant deaths occur in the neonate and the rest between 4 weeks and 1 year of age
o Lower SES families experience higher mortality rates across Canada
o Mortality rates are higher among Indigenous people
Sudden Infant Death Syndrome
 Sudden Infant Death Syndrome: sudden and unexpected death of an apparently healthy infant
under one year of age.
o Ninety percent of the cases occur in the postnatal period
 A safe sleep environment can reduce the risk of SIDS
Sensory Skills
 Vision
o Initially thought that newborns were blind (this is not the case)
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Visual Acuity
o The standard for visual acuity in adults in 20/20, which means that you can see and identify
something 20 feet away that the average person can also identify from 20 feet away
 20/100: you can see something 20 feet away that an ordinary person sees from 100
feet away
o At birth, visual acuity is 20/200 - 20/400 but it improves rapidly during the first year
(synaptogenesis, synaptic pruning, and myelination)
o Children reach adult levels of visual acuity at around age 7
Tracking Objects in the Visual Field
o Tracking: the process of following a moving object with our eyes
 Between 6-10 weeks tracking quickly becomes skillful.
Colour Vision
o Cones: necessary for perceiving red and green (present by 1 month)
Visual skills depend on a specific kind of visual stimulus
o Visual deprivation beginning at age 6 can prevent the development of normal peripheral
vision
Hearing and Other Senses
 Auditory Acuity
o Newborns’ auditory acuity is better than visual acuity
 Detecting Locations
o Because the ears are separate from each other, sound arrives at one ear before the other
(allows us to judge location)
o Finer-grained location of sounds is not well developed at birth
 Smelling and Tasting
o Smell and taste are related to each other
 Taste is detected by the taste buds of the tongue that register five basic flavours
 Sweet, sour, bitter, salty, umami
 Smell is registered in the mucous membranes on the nose
o Newborns prefer umami-flavoured and sweet foods due to their attraction to breast milk
(rich in sugars and glutamates)
 Senses of Touch and Motion
o Touch and motion may be the best developed
o The neonatal brain is responsive for gentle social touching
 May play an important role in early brain development, especially somatosensory
processing and the perception of tactile sensations
 Babies are sensitive to touches on the mouth, face, hands, and the soles of the feet
and abdomen
Perceptual Skills
 Perceptual Development
o Preference Technique: the baby is shown two pictures and the researcher keeps track of how
long the baby looks at each one.
o Habituation: getting used to a stimulus (characterized by a diminished rate of responding)
o Dishabituation: responding to a habituated stimulus as if it were new
Looking
 Early Visual Stimulation
o Visual stimulation in infancy is vital to proper development of visual perception


Infants given cataracts between 2-6 months did not develop the ability to
distinguish the relative position of facial features in the same way that normal
sighted people do.
o When early experience is lacking, visual capability fails to develop normally many years later
Depth Perception
o Possible to detect depth via:
 Binocular Cues: involves both eyes; each of which receives a slightly different visual
information of an object
 Pictorial Information/Monocular Cues: requires input from only on eye
 Interposition: when one object is partially in front of another object, you
know that the partially hidden object is farther away
 Linear Perspective: the impression that rail-road lines are getting close
together as they get farther apart.
 Kinetic Cues: cues that come from your own motion or the motion of some object
 Motion Parallax: if you move your head, objects near you seem to move
more than objects farther away
o Flinching is observed in 3-month-olds
o Order of the cues that the baby uses:
 Kinetic cues first (3 months), binocular cues next (4 months), and linear perspective
and other pictorial cues last (5-7 months)
What Babies Look At
 First two months, baby’s visual attention is guided by a search for meaningful patterns
 Between 2-3 months, the cortex has developed more fully, and the baby’s attention seems to shift
from where an object is to what an object is (more time is spent looking for patterns)
Faces: An Example of Responding to a Complex Pattern
 Babies prefer attractive faces
 Before 2 months of age, babies seem to look mostly at the outer edges of faces (hairline and the face
shape)
o Babies can’t distinguish mom’s face from a stranger’s if the hairline is covered
 After 4 months, covering the hairline did not affect the ability to recognize them
 At around 2-3 months, babies begin to focus on internal features of the face (eyes)
 At 6 months, infants are able to engage in reciprocal eye gaze with their parents (suggests that
babies are showing signs of active social communication)
Effects of Visual Deprivation
 Early visual input is necessary for alter development of face-processing expertise in adulthood
 Individuals deprived of early visual stimulation did not develop the ability to recognize faces in a
holistic manner (can’t process faces as a whole) rather they recognize faces as a collection of
independent facial features
 Deprivation also results in the failure to distinguish the relative spacing of facial features
 Adults who experienced deprivation also had difficulty identifying faces when head orientation or
facial expression changed.
Listening
 Discriminating Speech Sounds
o As early as 1 month, babies can discriminate between speech sounds (pa and ba)
o By 6 months, babies can discriminate between syllable words (baba and baga)
o
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Up to 6 months, babies can accurately discriminate all sound contrasts that appear in any
language
o By age 1, the ability to distinguish nonheard consonant contrasts begins to fade
o Accurate speech perception and language development involves more than just hearing
 It involves mouth movements and sound production
Discriminating Individual Sounds
o Newborn can tell mothers voice from another female voice but not the fathers.
Discriminating Other Sounds Patterns
o As early as 6 months of age, babies listen to melodies and recognize the patterns.
Intermodal Perception
 Intermodal Perception: how early can a baby learn something via one sense and transfer that
information to another sense.
o Can be present as early as 1 month and become common by 6 months
o IP helps babies adapt to and synchronize multisensory information flowing in from envir.
Explaining Perceptual Development
 Nativists claim that perceptual abilities were inborn
 Empiricists argue that these abilities are learned
Chapter 5 Notes
Cognitive Changes
 Piaget’s View of the First Two Years
o Assumed that a baby assimilates incoming information to the limited array of schemes she is
born with (looking, listening, sucking) and accommodates those schemes based on her
experiences
 Known as Sensorimotor Intelligence
o Sensorimotor stage is when infants develop and refine sensorimotor intelligence
 Sensorimotor Stage
o Substage 1: 0-1 month
 Tied to the present available information, forgets events from one encounter to the
next and does not appear to plan
 Primary Technique: Reflexes
o Substage 2: 1-4 months
 Marked by the beginning of the coordination between looking and listening, and
between reaching and sucking (exploring the world)
 Primary Circular Reactions:
 Simple repetitive actions organized around the infant’s body (sucking
thumb)
o Substage 3: 4-8 months
 Baby repeats some action to trigger a reaction outside her own body; a secondary
circular reaction (baby coos and mom smiles)
o Substage 4: 8-12 months
 Baby shows beginnings of understanding causal connections, at which point she
moves into exploratory high gear
 Means-end Behaviour:
 A consequence of the new exploratory drive where the baby has the ability
to keep a goal in mind and devise a plan to achieve it (move pillow to get
toy)
o Substage 5: 12-18 months
 Exploration of the environment becomes more focused; and tertiary circular
reactions appear
 Baby tries out various behaviours (trial and error)
 The baby’s behaviour has a purposeful, experimental quality but the baby
does not have mental symbols to stand for objects
o Substage 6: 18-24 months
 Has the ability to manipulate mental symbols such as words or images; allows infant
to generate solutions to problems simply by thinking about them without trial-anderror behaviour
 Object Permanence
o Object permanence: the understanding that something exists even when we are unable to
see it.
o Baby starts developing object permanence at around 2 months of age (substage 2)
 Baby at this stage show no signs of searching for a toy that fell off the bed
o In substage 3 (6-8 months), babies will look over the edge of the bed for dropped toys and
may also search for partially hidden objects
o In substage 4, infants will search for a toy that has been covered completely by a cloth
o By 12 months, most appear to grasp the basic understanding of object permanence
 Imitation
o
o
o
Infants could imitate actions that they themselves could make (hand gestures) as early as
the first few months of life
Cannot imitate facial gestures until substage 4 (8-12 months)
Deferred Imitation: child’s imitation of some action at a later time
 Only possible in substage 6, since it requires some internal representation
Changing Piaget’s View
 Object Permanence
o Piaget measured OP by looking at whether infants could move a blanket to retrieve a hidden
object; but they can’t move and grasp objects this way until 7-8 months
o Today’s research shows that babies as young as 4 months show clear signs of object
permanence if a visual response is used to test it
 Imitation
o Infants imitate some facial gestures (tongue protrusion) in the first weeks of life and
deferred imitation seems to occur earlier than Piaget proposed
 Young babies are capable of tactile-visual intermodal transfer
o Infant as young as 6 weeks can defer imitation and by 14 months, toddlers recall and imitate
actions as many as two days later
Alternative Approaches
 Object Concept: investigation of object permanence within the general concepts of understanding
what objects are and how they behave
o Babies are born with assumptions that guide their interactions with objects
 One assumption is the Connected Surface Principle: assumption that when two
objects are connected to each other, they belong to the same object
o Babies habituated to displays of two objects showed interest when two squares were
touching together to make a rectangle
o Violation of Expectancy: a research strategy where infant is habituated to a display that
depicts the movement of an object and then is shown another display where the object
moves in a way that goes against expectations
 Babies were uninterested in the consistent condition but interested in the
inconsistent condition; suggests that infants’ understanding of rules governing
relations amongst objects was more developed.
 Object Individuation: the understanding that an object seen at one time is the same object viewed
at another time
o Infants use three categories to individuate objects:
 First relies on Spatiotemporal Information: information about the location and
motion of objects; active at 4 months of age
 The second relies on object’s property information: the perceptual qualities of an
object such as colour, texture, and size; active at 10 months of age
 The third involves the development of distinct kinds of objects: duck vs. ball;
evident at 9-12 month of age
Conditioning and Modelling
 Classical conditioning in evident in infants as early as the first week of life
o Babies that experience smothering sensations while nursing on the right breast refuse to
nurse on the right side
 Operant conditioning is evident as well
o Pacifier Activated Lullaby (PAL) systems in neonatal intensive care units improves preterm
infants sucking reflexes, which in turn causes them to gain more weight

Infants also learn by watching models
o By 14 months, infants distinguish between successful and unsuccessful models and are more
likely to imitate those who succeed at an attempted task.
Schematic Learning
 Schematic Learning: the organizing of experiences into expectancies, or “known” combinations
o Expectancies (schemas) are built up over many exposures to experiences; helps distinguish
between familiar and unfamiliar
 One kind of schematic learning = CATEGORIES
o By 7 months, infants use categories to process information
 10 animal pics and if the 11th is also an animal pic; uninterested
 Categorical organization as a cognitive tool is not well developed in 7-month-old
o Cats and dogs (lower-level categories) in their eyes are not different and just belong to the
category of animals (higher-level categories)
 Higher level categories are known as superordinates and they include lower level.
o By 12 months, they understand the differences between both types of categories
 The idea that smaller categories are nested within larger categories are fully understood at age 5
Memory
 Newborns are able to remember auditory stimuli to which they are exposed while sleeping
 Babies (3 months) can remember objects and their actions with those objects over periods as long as
a week
o 3-month-old babies introduced to a mobile that speeds up when they kick their legs; when
mobile introduced several days later infants immediately start kicking their legs
 Infants as old as 3 months make association between objects that happen to appear together in their
physical surroundings
 Infants as young as 6 months form new associations with their memories of objects
 Infants memories are very specific, and they become less and less specific with age
Measuring Intelligence in Infancy
 Intelligence: an ability to take in information and use it to adapt to the environment
 Bayley Scales of Infant and Toddler Development: measures cognitive, language, and motor
development
o Primary use is to help identify infants and toddlers whore are in need of early intervention
for developmental delays
o The newer version, Bayley III has been found to be a strong predictor of intelligence-test
scores in preschoolers
 Limitation is that it underestimates the severity of impairment
 Habituation tasks to measure intelligence:
o Ex. How many times a pic needs to be shown before they lose interest
o Rate of habituation may predict later intelligence test scores
 Fagan Test of Infant Intelligence:
o Habituation rate – known as novelty preference and visual recognition are particularly
appropriate for infants who are incapable of responding to convention tests
 Ex. Infants who suffer from cerebral palsy can’t perform tasks on the Bayley
 Predicting IQ based on infant measures is difficult because several factors can modify IQ
 Neurotoxins like Fluoride in excessive amounts can contribute to skeletal fluorosis: motted or pitted
teeth in children and brittle bone in later life
o Environments with high F concentrations is correlated with lower IQ scores
Theoretical Perspectives of Language Development
 Behaviourist: B.F. Skinner
o Main Idea: infants learn language through parental reinforcement of word-like sounds and
correct grammar.
o Example: When babies babble, they resemble real words and parents respond to them with
praise and encouragement which serve as reinforcers.
 Nativist: Noam Chomsky
o Main Idea: innate language processor called the language acquisition device (LAD), contains
the basic grammatical structure of all human language and guides children language dev.
o Example: LAD tells infants what characteristics of language to look for in the speech they are
exposed to.
 Two basic types of sounds, consonants and vowels, and teaches them to divide the
speech into two categories so they can analyze and learn the language they are
hearing.
 Interactionist: Bowerman, Tomasello, Vygotsky, Werker
o Main Idea: infants are biologically prepared with perceptual and motor readiness to attend
and produce language and that language development is a subprocess or neuro-cogn. devel
 Social interactions are critical to language development
o Example: From the beginning the child’s intent is to communicate
Influences on Language Development
 Infant-Directed Speech: a way of speaking where older children speak differently to infants than
they do to preschoolers
o Speak in a higher pitch and may also repeat the child’s own sentences but in slightly longer,
more grammatically correct forms (expansion/recasting)
 IDS may be important for language and grammar development
o The sheer quantities of language a child hears and child-caregiver interactions are significant
in language development
Early Milestones of Language Development
 From birth to 1 month, the most common sound an infant makes is a cry
 Over the next few months, the number of ways in which a baby can express herself increases
tremendously
 Language acquisition has two transitional stages: “reorganization of communication sounds” and
“reorganization in infants”
o Newborns display a sensitivity to speech sounds; by 2 ½ months infants show a strong
preference to complex speech sounds compared to nonspeech sounds; at 4-6 months
infants are sensitive to all the essential speech sounds that correspond to language
o Perceptual transition occurs during 10-12 months of age where infants can’t distinguish
between subtle language sounds that lie beyond their dominant language
 Infants 4-6 months can detect when a different language is spoken when shown a silent video
o By 8 months monolingual infants cannot, but bilingual infants can
 The ability to identify and remember word-object associations appears at 14 months of age
 Infant differentiate words into two categories:
o Grammatical: words that are primarily structural (articles, prepositions, auxillaries) and are
generally of short vowel duration and have a simple syllable structure
o Lexical: high meaning (nouns, verbs, adjectives) and these words tend to be longer and
complex; by 6 months infants prefer these words
Language Acquisition and Word Learning
 2.5 months: can distinguish between speech and non-speech sounds and have a preference for
complex speech sounds over non-speech sounds
 4 to 6 months: sensitivity to all essential speech sounds; can detect when a speaker changes
language between French and English
 6 to 8 months: bilingual and monolingual infants respond similarly to French and English; bilingual
infants can detect language switches, but infants raised in English cannot (8 months); cannot
associate random words to objects; notice subtle differences in speech and sounds; at 6 months can
differentiate between grammatical and lexical (preferred) words.
 10 to 12 months: Can only distinguish subtle sounds in their own language
 14 months: can learn and remember associations between words and objects
First Sounds and Gestures
 Cooing: at about 1 or 2 months
 At 4 months of age, infants’ voice pitch becomes predictive of voice pitch later in childhood (higher
pitched cries predict higher-pitched voices)
 Consonant sounds appear at about 6 or 7 months
 Babbling: mix of consonant sounds and vowel sounds (6-7 months)
 The left side of the brain controls the right side and language capacity is based in the left
hemisphere; when infants babbled, they used a “right mouth openings” signalling the beginning of
language production
 Through babbling, infants learn the intonational pattern of the language they are hearing
o A rising intonation signals a desire for a response
o A falling intonation requires no response
 At around 9 to 10 months, gestural language appears where babies begin “demanding” for things by
using gestures (stretch hand out if they want us to hold it)
Word Recognition
 Babies start storing individual words in their memories at around 6 months of age and by 9 or 10
months most understand the meanings of 20 to 30 words.
 Receptive Language: the ability to understand words
The First Words
 Expressive Language: the ability to produce, as well as understand and respond to meaningful words
(appears around 12 or 13 months)
 Often the child’s first words are used in specific situations and in the presence of many cues
 Holophrases: the combination of a single word with a gesture to create a “two word meaning” (point
to father’s shoe and say Daddy).
 Naming Explosion: period between 16 and 24 months, children begin to add new words rapidly
o Most of the new words are for things or people
o Most infants learn nouns before verbs
The First Sentences
 Sentences appear when a child has reached a threshold vocabulary of 100-200 words (18-24 months)
 Features of first sentences: short, two or three words, and are simple (known as telegraphic speech)
o Nouns and verbs are included but grammatical markers (inflections) are missing
Individual Differences in Language Development
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Infants growing in bilingual homes will after 2 years speak in the mom’s dominant language with
mom and the dad’s dominant language with dad
Bilingual children had better performance in working memory tasks and have a greater ability to
focus attention on language tasks (exposure needs to be regular)
Bilingualism acts as a buffer against the onset of Alzheimer’s
Differences in Rate
 Some children use individual words at 8 months, others not until 18 months, and some do not use
two-word sentences until 3 years or later
o Infants who talk late typically catch up
o Those who don’t catch up are primarily children who have poor receptive language
development (see professional if this is the case)
 Boys have speech delays more often than girls
 Infants who experienced language-based social interactions were less likely to be late talkers
Language Development Across Cultures
 Babies “coo” before they “babble”; they understand language before they speak; most babies begin
to use their first words at about 12 months
 Holophrases precede telegraphic speech which begins at 18 months
 The word order a child uses is not universal
o Some cultures noun/verb is common and in others verb/noun is common
 Inflections are learned in varying orders
o Japanese children use pragmatic markers that indicates feeling or context
 “yo” at the end of sentence when facing resistance and “ne” when the speaker
expects approval
 Children learning Turkey use essentially the full set of noun and verb inflection by age 2 and never go
through a stage of using uninflected words; language is simple but ungrammatical.