Modules 1-4 Flashcards
Themes and Theories, Developmental Principles, Prenatal and Neonatal Development
Developmental Science
how and why change occurs over time
Domains of Child Development
- Physical: biological change
- Cognitive: the way we think/understand
- Social-emotional: the ways we learn to connect with others and regulate emotion
Major Themes
Nature and Nurture
Continuity and Discontinuity
Stability and Plasticity
Active and Passive Influences
Universal and Individual Differences
Nature and Nurture
what is the balance between genetic and environmental contributions to development?
Continuity and Discontinuity
does development happen in small changes over a long period (continuous) or spurts of dramatic change (discontinuous) ?
Continuity = quantitative = increment theory
ex: child gaining knowledge, tree getting bigger
Discontinuity = qualitative = stage theory
ex: walking to crawling, caterpillar to butterfly
Stability and Plasticity
how much change remains possible as we move through development?
Stability = cannot be changed (more in late life)
ex: stroke in late life = struggle
Plasticity = a lot of change left (more in early life)
ex: hemispherectomy in early life = normal function
Active and Passive Influences
how much does someone contribute to their own developmental path?
(whats happening to them vs whats in their control?)
ex: what a child chooses to pay attention to
Universal and Individual Differences
are there parts of development that are common to everyone while other parts are individually unique?
ex: all brains have similar basic structure, but a lot of variation
Intersectionality
characteristics intersect and create unique developmental paths
Niche Picking
people actively seek out environments that are a good fit with their genetic makeup
Parental Ethnotheories
how cultural context impacts development
The primary developmental research designs are….
Cross Sectional
Longitudinal
Cross Sectional Research
separate groups studied at the same time
ex: 6 year olds vs 8 Year olds
Longitudinal Research
one group studied over time
ex: same group of children at 1 month, 3 months, 5 months…
Scientific Inquiry
1) hypothesis
2) data
3) theory
Hypothesis
a testable idea or prediction
Data
information known by direct experience or observation
Theory
a coherent set of propositions that explain observations and are supported by evidence
Theories help us…
organize and predict
Major Theories (3 Types)
1) Individual Environment Processes
2) Dyadic (Social) Processes
3) Multi-Level Processes
Individual Environment Processes
relate the individual to their environment
Includes: Nativism, Behaviorism, Piaget’s Constructivism, Information Processing
Dyadic (Social) Processes
how social relationships contribute to developmental outcomes
Includes: Psychodynamic, Attachment, Social Learning, Sociocultural
Multi-Level Processes
more modern, complex interaction of context of development
Includes: Ecological, Systems
Nativism (Chomsky)
development is driven entirely by biology
- ability to process info is innate
Behaviorism (Watson)
development is entirely through environment
- focus on learning, role of positive and negative reinforcement
Piaget’s Constructivism
children actively create cognition by interacting with the world
- Stage Theory (discontinuous): dramatic change occurs at ages 2, 7, 12. All children progress in the same order.
Information Processing
we think in a step by step process like computers
input –> process –> output
continuous, incremental, gradual development
Psychodynamic Theory (Freud)
personality development is driven by social interactions and satisfying basic drives
FIRST stage theory
Attachment Theory (Bowlby)
infants behave in ways that promote bonding with their caregiver (evolved for survival)
quality of attachment can vary
Social Learning Theory (Bandura)
developmental outcomes depend on social partners responses
learning happens in a social context, continuous learning through observation (ex: bobo doll)
Sociocultural Theory (Vygotsky)
how thinking develops in social and cultural context
we can best understand cognitive development in the context of an interaction with a skilled helper
- zone of proximal development
- scaffold
Zone of Proximal Development
(part of sociocultural theory)
the space between where a child’s skill level actually is and their potential for improvement
Scaffold
(part of sociocultural theory)
any temporary tool/framework that can help a child reach the next level
Ecological Theory
development is characterized by constant interactions between the child and the context they live in
- places child in center
1) microsystem: immediate context
ex: family, school
2) mesosystem: contexts interact across each other
ex: family interacts with school
3) exosystem: external context, indirect affect
ex: parents workplace
4) macrosystem: cultural customs
5) chronosystem: age of child, time in history
Systems Theory
ecological systems theory + BIOLOGY
all factors influencing development form a cohesive system
- Child is moved outward, bio context added
must understand how factors work together and influence each other
Genetic Expression
process of genetic info being turned into biological products
(how genes are used)
Genotype (STATIC)
the genes a person has for a particular characteristic
Phenotype
the characteristics that are expressed in that person
A fertilized egg contains…
23 chromosomes
Genes have regions that…
regions that CODE for protein
regions that REGULATE their activity (on/off switch)
Homozygous alleles
same bases
Heterozygous alleles
different bases
Mendelian Genetics
dominant and recessive traits
(punnet square)
1 dominant allele = trait appear
or
2 recessive alleles = trait appear
Complex Genetic Effects
interaction of multiple genes = development of organ systems and complex behaviors
Polygenic Inheritance
interaction of many genes = one outcome
Pleiotrophy
a single gene = many outcomes
Genetic Mutations
changes that occur in the structure of genes
can be inherited or because of toxin exposure
Chromosomal Disorders
caused by wrong number of chromosomes
ex: down syndrome
Single Gene Disorders
any disorder caused by the function or lack of function of a single gene
ex: sickle cell, cystic fybrosis
Interventions for genetic disorders are…
modify environment
gene therapy
CRISPR
Gene Therapy
use viruses to “infect” cells with healthy genes to replace disordered genes
CRISPR
direct gene editing to turn genes on/off
Polymorphism
a normal mutation, allows for variability in gene pool needed for evolution
Behavioral Genomics
research relationship between normal polymorphisms and behavioral outcomes
(polymorphisms x behavior)
- Candidate Gene Approach
- Genome-wide Association Studies (GWAS)
Candidate Gene Approach
target a specific gene –> is a specific allele more common in people with this behavior?
Genome-wide Association Studies (GWAS)
look at entire genome at once to identify relevant genes
Genome
the complete set of genes or genetic material present in a cell or organism
Behavioral Genetics
research the amount of influence of genetic and environmental factors on specific behavioral outcomes
(genes and environment x behavior)
Methods of behavioral genetics are…
Adopted Children
- genetic background from bio parents x environment from adoptive parents
—> outcome more similar to bio or adopt parents?
Monozygotic vs Dizygotc Twin Studies
- monozygotic (identical) = share genome
-dizygotic (fraternal) = genomes of regular siblings
—> is outcome more similar between MZ or DZ twins?
Heritability
any developmental outcome has a range of variability, score of 0 to 1
0 = all environment
0.5 = equal
1 = all genetic
score tells us if an outcome is more or less influenced by genetics
Epigenetics
how environment influences gene expression
ex: rat study
Gene-Environment Correlations
how genes influence environment
- Passive = genes match with environment that promotes expression
(ex: parents like reading –> pass reading genes and make reading environment) - Evocative = genes contribute to behaviors that evoke response from environment
(ex: calm baby gets more attention) - Active: genes contribute to a tendency to seek environment that matches personality
(ex: thrill seeking )
Development is the result of…
continuous, bidirectional interactions between
biology x environment x time
Cummulative: development builds on what comes before and adds something new
- some things need to happen first
Non-linear
Developmental Pathways
every individual has their own unique, non-linear pathway that reflects their cumulative history of genetic x context interactions over time
Multifinality vs Equifinality
Multifinality
similar starting point —> different outcomes
Equifinality
different starting points —> similar outcomes
Human gestation lasts….
40 weeks, at least 37 to be full term
below 37 weeks = premature
The 3 periods of human gestation are….
1) Germinal Period (0 - 14 days)
2) Embryonic Period (wk 2 - 8)
3) Fetal Period (wk 9 - birth)
In the Germinal Period (0-2 wks):
1) Fertilization
2) Development of the morula
3) Development of the blastocyst
4) Implantation
Fertilization
1) ovum released from ovaries
2) travels to fallopian tube, fertilized by 1 sperm = zygote
3) zygote moves to uterus
4) cell division, building up…
Development of the morula
solid spherical mass of 16 cells
3-4 days after fertilization
Development of the blastocyst
cells in spherical shape with hollow cavity inside
made of:
- embryonic disk / inner cell mass (pre-embryo), puripotent cells can become anything
- trophoblast (pre-support system)
Implantation
trophoblast cells secure stable implant to uterus lining, grow into uterus to establish nourishment from mother
failure to implant = chemical pregnancy (miscarriage, 60%)
In the Embryonic Period (2-8 wks):
1) embryo develops from embryonic disk
2) support system develops from trophoblast cells
3) differentiation of inner cell mass
4) organogenesis
In the embryonic period, trophoblast cells split into….
2 fetal membranes:
- Chorion: outer membrane, pre placenta and cord
- Amnion: inner membrane filled with protective fluid
The placenta….
develops from the chorionic membrane in embryonic period
transfers oxygen and nutrients from mother’s blood, removes fetal waste
sensory organ for embryo: connects them to outside environment, substances can cross through placenta
In the embryonic period, the embryonic disk splits into….
3 layers:
- Ectoderm (outer layer): becomes brain, spinal cord…
- Mesoderm (mid layer)
- Endoderm (inner layer)
Organogenesis
development of all major organ systems (from the head down)
heartbeat = 4 wks
brain develop = 3-4 wks
disruption of organogenesis = miscarriage or malformations
In the Fetal Period (9-40 wks):
GROWTH
Sexual differentiation
Fetal hearing and vision
Fetal learning
- progressive, not all at once
Sexual Differentiation
- same genitalia until 9 wks
- androgen = male
- no androgen = female
- androgen production also affects brain development
- blood test can determine sex at 9-10 wks
Fetal Hearing
sensitive to sounds at 16-18 wks
- full hearing by 27 wks
- most sensitive to mothers voice
Fetal Vision
can first detect light at 16 wks
- eyes are mostly developed by 26 wks
Fetal Learning
32 wk old fetus can detect stimulus and change in stimulus
ex: Cat and the Hat experiment
Teratogens
environmental agents that cause deviations from normal development, and can lead to abnormalities or death
- presence of toxic agents or absence of necessary agents
Effect of tetratogens depends on…
Nature: what was the agent?
Timing: when in development did exposure occur?
Duration: how long did the exposure last?
Alcohol and Drugs in prenatal development cause…
- physical malformations (esp. facial) and growth problems
- cognitive and behavioral symptoms
severity depends on extent of exposure
Prescription Drugs: some always dangerous, some more complicated (weigh pros vs cons)
ex: Fetal Alcohol Spectrum Disorder (FASD)
Chronic, toxic stress in prenatal development causes….
- premature birth, low BW
- behavioral dysregulation
stress = release of stress hormone cortisol
Stress Inoculation Hypothesis: manageable levels of stress may also benefit child later
Severe malnutrition in prenatal development causes….
- 1st trim: brain abnormalities, premature birth, death
- 3rd trim: delayed growth, low BW
linked to health problems later in life
Oxytocin
“cuddle chemical”
increase during delivery to prepare body and promote bonding
Couvade
experiencing symptoms of pregnancy
mother and father both experience hormonal change
—> can predict positive emotional response
- ritualistic: feigning contractions
- psychosomatic: weight gain, nausea, mood swings
Maternal Mortality
death of a woman during pregnancy, at delivery, or soon after
rates increased in U.S.
(inadequate prenatal care, chronic illness, increased maternal age, higher obesity rates, focus on infant over mom)
racial disparities: 3x higher for black mothers
Premature Birth
earlier than 37 wks
10% of U.S. births
earlier birth = more complications (25 wks = viable)
Late-Preterm
34 - 37 wk premature births
- show more behavioral concerns later
Premature birth risk factors:
socioeconomic status (SES)
multiple births (ex: twins)
many pregnancies close together
maternal age
tetratogens
Typical full term birth weight:
7.5 lbs
(range = 5.5 - 10 lbs)
Intrauterine Growth Retardation (IUGR)
a fetus that is small for its gestational age
Premature infants birth weight is…
usually low, but consistent with gestational age
Low BW = under 5 lbs
Very Low BW = under 3 lbs
Small for Gestational Age
full term infant with low birth weight
Common Problems in Preterm Infants
- Immature lungs (leading cause of death)
- Brain bleed
- State regulation
Kangaroo Care
skin to skin contact with preterm infants
Infant States
regulate sensory input
- Sleep (50% REM / active sleep)
- Smile
- Cry
- Move
- Hearing/Vision
Neuron
basic cellular unit of brain
- electrical signaling within neuron
- chemical signaling between neurons
Major components of neuron
cell body/ soma
dendrites (receiving end)
axon (transmitting end)
synapse (space between 2 neurons where axon meets dendrites)
Gyrus
squishy parts of brain
Sulcus
folds in the brain
Grey Matter
cell bodies / dendrites
White Matter
axon bundles
7 Processes of Brain Development
first 4 = prenatal
last 3 = continue postnatal and beyond
1) Neuralation
2) Neurogenesis
3) Neural Differentiation
4) Neural Migration
5) Mylenation
6) Synaptogenesis
7) Synaptic Pruning
*processes are overlapping, not sequential
Neuralation
3 wks after fertilization
ectoderm folds to form neural tube (brain and spinal cord)
and neural crest (peripheral nervous system
neural tube —> central nervous system
Disorders of Neuralation
- Spinda Bifida: bottom end of neural tube fails to close
(spinal cord protrudes) - Anecephaly: top end of neural tube fails to close
(brain fails to fully develop)
folic acid associated with a reduced risk of neural tube defects
Neurogenesis (birth of neurons)
week 5
1) pluripotent cells differentiate to form neural precursor cells
2) neural precursor cells divide, generate a large number of newborn neurons
*all neurons generated INSIDE neural tube
Neural Differentiation
neural precursor cells in neural tub differentiate into neuron sub-types and supporting cells (neurons vs glial cells)
Neural Migration
adult cortex = 6 layers of cells
neurons move from birthplace in neural tube to their proper place in the brain
- supports brain growth
- builds brain structure
Myelination
myelin = white matter (supporting glial cell, lipid based)
wraps around axon to improve insulation and speed of transmission
*linear process: begins prenatally but continues through adulthood
Synaptogenesis (birth of synapses)
every neuron forms thousands of new connections, rapid production right before and after birth
*back of brain develops before front
Synaptic Pruning
elimination of some proportion of synapses
- Aptosis: programmed cell death
- Experience-Based: brain adjusts the synapses it uses based on experience
*timing varies by brain region (back to front)
Neural Plasticity
changes in the strength of connections between neurons
- Hebb’s Law: use it or lose it
Experience-Expectant Plasticity
because of evolution, the nervous system “expects” to receive species typical experiences
- neural connections are not pre-wired, but similar connections for all members of the species (if typical experience)
Experience Dependent Plasticity
Learning
neural connections form based on individual experiences
