notes Flashcards
how is knowledge acquired?
complex question
theories
based on preconception
much of dev psych is based on two worldviews
Prenatal Development (fetus)
Earlier development takes place at a more rapid pace than later development
Head develops earlier than areas farther from the head (cephalocaudal dev’t)
brain development happening
Sensitive periods: Period of time when a developing organism is sensitive to the effects of external factors.
Teratogens
prenatal sensitive periods
first 38 weeks of development
first 8 weeks of embryo there is the potential to suffer or get major abnormalities
Example of sensitive periods for prenatal dev’t:
Teratogens:
External agent that can cause damage during prenatal development
only cause damage in sensitive periods
E.g. Smoking, alcohol, stress, environmental pollutants
Mercury
thalidomide – prescribed for morning sickness
Many teratogens cause damage only if they are present during a sensitive period in prenatal development
Sleeper effects = delayed consequences
Fetal Learning
how do we know what a fetus knows?
Prenatal studies (e.g. Eugene Emory)
Ultrasound techniques
fetus movement
Newborn studies
Habituation - decreased response to a continued stimulus. (bored) loss of attention
bored means we’ve learned that thing, ex. voice
classical condition, puff of air
fetus activity
fetus activity differed from depressed, non-depressed mothers
able to use ultrasound and other techniques to understand fetal activity
Methods for studying prenatal learning and infant dev’t
Habituation
VOE (looking time)
Preferential Looking
Habituation
what is it and how do we know if an organism has habituated?
Decreased response to an increased stimulus indicates memory has formed (infants 30w)
How do we use habituation to understand what preverbal infants know?
before they can speak and tell us response
Increased response to a novel stimulus
VoE
violation of expectation
measure we use to determine or identity what infants may expect to happen
gaze behaviour or looking time
possible event or impossible event
Newborn babies prefer mother’s voice over a stranger’s voice
Recognize mothers voice Kisilevsky et al. (2003) p.54
Mother read poem
Test: Mother & stranger (same poem)
Results – heart rate increased to mother and decreased to stranger
Newborn preferred mother
Suggests that babies learn mothers voice in the womb
Fetal Learning (tested in newborns)
recognize rhymes and stories presented before birth.
prefer smells, tastes, & sound patterns that are familiar because of prenatal exposure.
prefer familiar sound patterns at birth
test: two stories, prefer familiar story
Newborns remember scent of amniotic fluid
Marlier et al., 1998
Newborns presented with two pads
One saturated in their own amniotic fluid and the other saturated in that of another baby
Presented with two pads on either side of head
Preference indicated by head orienting toward own fluid scent
Newborns remember scent of amniotic fluid
Marlier et al., 1998
Newborns presented with two pads
One saturated in their own amniotic fluid and the other saturated in that of another baby
Presented with two pads on either side of head
Preference indicated by head orienting toward own fluid scent
Newborns prefer language exposed to (native lang. of mother)
Newborns demonstrate a preference to the language they heard in the womb.
Babies exposed to French language prenatally, preferred French language at birth, compared to Russian
and vice versa for babies exposed to Russian language prenatally
Newborns demonstrate food preferences to foods exposed to prenatally
Experiment and control group
Mothers in experimental group were asked to drink carrot juice during last trimester
Babies (5.5 mos) given preference test (cereal mixed with water or carrot juice)
Babies exposed to carrot juice in womb, preferred it at 5.5 months
newborn states
quiet sleep 8h
active sleep 8h
drowsing 1h
alert awake 2.5h
active awake 2.5 h
crying 2h
colic
Baby colic (also known as infantile colic) is defined as episodes of crying for more than three hours a day for more than three days a week for three weeks in an otherwise healthy child between the ages of two weeks and four months. The cause of the colic is generally unknown.
sleep
REM sleep (not the quiet, deep sleep kind!) constitutes fully 50% of a newborn’s total sleep time and declines rapidly to only 20% by 3 or 4 years of age…
Crying
Early in infancy, crying reflects discomfort or frustration
Crying gradually becomes more of a communicative act
Many effective soothing techniques…moderately intense and continuous or repetitive stimulation
techniques to reduce crying:
Swaddling, soothing, rocking, singing, shhh-ing, repetitive motions and sounds, carrying and increased holding
culture and crying
Crying among a hunter-gatherer group (!Kung San) – Botswana
Bouts of crying same across cultures
Duration of crying different!
frequency was the same across cultures
Newborn Reflexes
Reflexes
Involuntary, unlearned responses
Rooting, sucking, grasp, foot curl, stepping, motor reflexes (twisting/fists), morrow (falling), blinking, sneezing, gaging, pupil dilation\
Low Birth Weight (LBW) Infants
less than 5.5 pds
< 35 weeks is ‘premature’
If birth weight is less than the norm for their gestational age, they are referred to as ‘small for gestational age (SGA)’
Social disparities
Infants born in Nunavut and NWT are 2-3x more likely to die before 1yr than infants born in BC…NS.
Why?
Access to health care
Poverty
SIDS
Sudden Infant Death Syndrome
Sudden, unexpected death of an infant less than 1 yr that has no identifiable cause.
Typically healthy, 2-5 mos
5 steps to reduce risk:
Back to sleep
No smoking (before or after the birth)
Firm bedding (no pillow, crib bumpers)
Not too warm (overly warm is associated w/ SIDS)
Breastfeed (when you can!)
Cause of SIDS unknown, but…
Studied babies who died of SIDS in the last two decades
Neurochemical abnormalities in the brainstem
Brainstem regulates breathing, heart rate, temperature
Theory – babies did not wake due to overheating or lack of ventilation
Newborn
Temperament
Individual and group differences
(Aime, Rochat and Broesch, 2020)
Uniqueness of Human Thinking
Guiding questions:
What makes human thinking unique?
How does it develop?
Why study development?
Practical applications (education, parenting, policies, atypical development)
Understanding development means understanding the process that leads to adult human thinking (including perception, emotion, decision making etc.)
Theories (worldviews)
Nativism – emphasis on biology and the unfolding of innate skills and abilities.
Empiricism – the mind is a passive, empty container and content arrives in the mind.
Humans are biological and social.
There is no such thing as a baby. Babies are embedded in a complex social world.
week 3: relations between biology and psychology
Understand the ways we can think about the complex interplay of nature & nurture
Be able to describe epigenetics
Know the structures of the brain and the developmental processes of brain development
Know how early experience can shape development via sensitive periods and plasticity (know examples in detail)
why is Nature and Nurture important
-Key concepts
-What do we mean?
-Why is this a meaningful question in development?
-What is epigenetics and why should we care about it?
important terms week 3
Genes, genotype, heritability, gene expression
Phenotype
Epigenetics & heritability
Innate
Learned
Nativist perspective
Relational perspective
Plasticity
Sensitive periods
nature
refers to genes or genetic material
genes you are born with
genes not just passed down, experiences can shape genetic makeup
can’t consider nature without considering nurture
nurture
early experiences, prenatal experiences
experiences can shape who you are
What do we mean by nature AND nurture?
-How these complex relationships shape/contribute to a developing child.
-NOT usually the independent contributions of each.
-The ultimate goal is to understand the relative contributions of each.
-Not only can we not separate these variables, they are intertwined and overlapping, often influencing each other in complex ways.
-we want there to be a simple explanation but its usually a combination
Nature and Nurture
Genetic and environmental influences
The interplay between genes and experience is very complex.
This model of hereditary and environmental influences can help to simplify this interplay.
How does the environment shape your phenotype?
Your phenotype (observable characteristics) result from an interaction between environment & genotype
Think: gene for long legs? Perhaps this is enhanced with parenting practices w/ motor dev’t?
Child’s Phenotype and Environment
Children are active creators of the environment in which they live.
By virtue of their nature and behaviour, they evoke certain kinds of responses from others.
They also actively select surroundings and experiences that support their interests, talents, and personality characteristics.
How do we study brain development
2 examples:
FMRI
-Functional magnetic resonance imaging
-Magnet detects cerebral blood flow (bowl of jelly)
-Increased blood flow = increased activity
ERP’s (EEG) – EVENT RELATED POTENTIALS
(USING ELECTROENCEPHELOGRAPHIC)
-Recordings of electrical activity in the brain
-Electrodes
-Brain-behaviour relations