Psychology 101: Developmental Psychology
Professor Caren Walker
Lecture 1 – 4/2/24
What's wrong with “nature vs nurture”?
● Newborns show preferences to attend to certain objects “active child” and are motivated to learn
● Practice language when alone; babbling
● Actively selecting their own environment increases w/ age
● Continuous (quantitative change) development vs discontinuous (qualitative change)
development → Stage Theories
● Perceptual, brain, strategy, problem-solving, etc. mechanisms of change
● Individual differences = growing field of developmental psychology; what causes individual
variation across people?
Lecture 2 – 4/4/24
● “Controlled rearing studies” aka deprivation studies; what experience is needed to develop depth
perception?
● We need visual AND motor experience
● Poverty of the stimulus argument: there isn’t enough information from the environment to learn
everything about the stimulus
The Problem of Knowledge
● The Meno = socrates and the boy – socrates is asking slave boy questions; concludes that the boy
must already know the proofs of geometry (must have been born w/ it)
○ You know everything you’re going to know, do not need to learn it → “the recollection of
the soul”; knowledge is inherited from previous lives before us (Socrates)
● Aristotle: we are born with nothing and learn everything over time through experience
● Common themes between the two philosophers: influences of nature/nurture & interested in the
proper raising of children
○ Plato = discipline and self-control
○ Aristotle = different children should be raised according to their unique needs
● Rene Descartes: argues for the role of nature and development; mind is a part of the body that
naturally grows, similar to limbs; cognition as a “mental organ”
● Noam Chomsky: argues for nature; we are biologically predisposed to learn language (LAD)
● John Locke: argues for nurture, “blank slate” – we etch things onto our blank slate through
learning; argues that parents initially impose strict rules, but later grant freedom
● David Hume: argues for nurture; children learn through cause and effect
● 1800s and early 1900s beginning of empirical revolution; study negative outcomes of children
factory workers during industrial revolution
○ Charles Darwin drew parallels between human prenatal growth and other animals’
○ Kept a diary of his own child's development over time; systematic observations
● Sigmund Freud: behavior is motivated by innate, unconscious, instinctual drives
○ The type of drive changes over development and are characterized by universal stages
● Behaviorism: study only directly observable things (Skinner and Watson); no mental phenomena
“thoughts”, “concepts”, “beliefs”, “consciousness”... believed the had no solid explanation
, ○ Based off of Pavlov’s classical conditioning; nurture can overcome nature
○ Skinner’s operant conditioning = positive/negative reinforcement can be used to shape
behavior
● Watson’s Little Albert Study (1920): conditioned baby to be scared of rat through loud noise
association – fear generalized to other fuzzy things as well
● Behaviorism was a response to eugenics (Francis Galton) belief that the human race can be
improved by selecting for traits in population; coined the phrase “nature vs nurture”
● Cognitive Revolution: to explain behavior, we have to think about the mind and mental processes;
the mind is like a computer that processes information
● Jean Piaget = father of developmental psychology; founded the field of cognitive development
○ Studied nearly every aspect of child cognition (like a zoologist)
○ Invented simple and clever tasks to test his ideas; scientific study of development
● Development happens in stages – discontinuous development (challenged/not supported)
● Learning is a constructive and active process in which the child is a little scientist
● Leo Vygotsky: child in cultural context is unit of study; social environment and influences of the
outside world changes how we develop
○ Process of internalizing social and cultural information; mechanism = social interaction
● Modern psychology still deals w/ the question of nature vs nurture
Lecture 3 – 4/9/24
● Heredity: chromosomes contain genes that get turned on/off and each pair may have slightly
different versions of the same gene (allele) → each allele carries instructions for a specific
variation on a trait
● Alleles can be dominant or recessive, and homozygous or heterozygous
● Genetic diversity can occur through crossing over = process by which sections of DNA switch
from one chromosome to another; promotes variability
● Mutation = section of DNA is changed; spontaneous error
● Different environments can lead to different development
● Maple syrup urine disease: disorder related to a defective recessive genes; cannot metabolize
three branched-chain amino acids (urine smells like maple syrup); if caught early on, a special
diet can help avoid impairments
● Children are a source of their own development; seek surroundings to match their interests and
personalities
● Epigenetics: study of stable changes in gene expression that are mediated by the environment
○ Methylation – common epigenetic mechanism where molecules block transcription
● Heritability: statistical estimate of the proportion of the measured variance on a trait among
individuals in a given population that is attributable to genetic differences among individuals
○ Heritability only applies to a particular population living in a particular environment
Ecological Theories
● Ethology: study of a behavior within an evolutionary context (adaptive survival value)
● Imprinting = some species of birds follow mother during a critical period – biologically
predisposed
● Evolutionary psychology: play is an evolved platform for learning during period of immaturity
for most mammals
, ● Parental-investment theory = stresses the evolutionary basis of many aspects of parental behavior
benefit their offspring
○ Cinderella effect: child maltreatment are higher for stepparents than biological parents
● Bioecological model: environment is a “set of nested structures” -Urie Bronfenbrenner
○ Every level has an impact on development, but differ in how immediate their effects are
● Microsystem = immediate environment an individual personally experiences
● Mesosystem = inter-connections among various microsystems
● Exosystem = environmental settings that a person experiences indirectly (e.g. parent’s working
hours)
● Macrosystem = larger cultural and social context
● Chronosystem = historical changes that influences the other systems (e.g. remote learning during
pandemic)
● Gene/environment interaction example: himalayan rabbit – environment effects that expression of
genes for fur color (ice pack turned fur black)
● Behavior genetics: twin studies (monozygotic and dizygotic)
○ Comparing personality traits between identical twins and fraternal twins – environment
plays a role in influencing personality
○ Minnesota twin studies: extensive study of identical twins separated early in life
● Adoption studies allow us to see if children are more similar to adoptive parents (environment) or
biological parents (genetics)
● Molecular genetics: science that examines specific DNA sequences to identify mechanisms that
link genes and behavior
○ Genetic factor accounts for about 50% of the influence of socioeconomic status and
educational achievement
● Summary = genetics and environment interact to influence development
Lecture 4 – 4/11/24
● Early ideas about prenatal development:
1. Quantitative Change = “preformationism”; ‘spermists’ vs ‘ovists’
a. Present idea until the 1800s
2. Qualitative Change = epigenesis (Aristotle) cells multiply and differentiate
a. Not embraced until modern study of embryology
● REMINDER → due next wednesday 4/17 Pop Science Response 1
● Stem cells: cells that have not yet differentiated into specialized cells; flexible and powerful
regenerative tool
● Developmental process includes cell division, cell migration, cell differentiation, and finally cell
death
○ Cell death example – webbing between fingers and toes gradually dies
● Fetus is considered viable at 28 weeks (viability means they can sustain themselves outside the
womb)
● Prenatal Phases: zygote (1-2 weeks), embryo (2-8 weeks), fetus (9-38 weeks)
○ Zygote: fertilization, implantation, placenta formation
○ Embryo: layers of cells, neural tube, limbs, organs form
○ Fetus: movement, sensory abilities, rapid growth, brain development
Professor Caren Walker
Lecture 1 – 4/2/24
What's wrong with “nature vs nurture”?
● Newborns show preferences to attend to certain objects “active child” and are motivated to learn
● Practice language when alone; babbling
● Actively selecting their own environment increases w/ age
● Continuous (quantitative change) development vs discontinuous (qualitative change)
development → Stage Theories
● Perceptual, brain, strategy, problem-solving, etc. mechanisms of change
● Individual differences = growing field of developmental psychology; what causes individual
variation across people?
Lecture 2 – 4/4/24
● “Controlled rearing studies” aka deprivation studies; what experience is needed to develop depth
perception?
● We need visual AND motor experience
● Poverty of the stimulus argument: there isn’t enough information from the environment to learn
everything about the stimulus
The Problem of Knowledge
● The Meno = socrates and the boy – socrates is asking slave boy questions; concludes that the boy
must already know the proofs of geometry (must have been born w/ it)
○ You know everything you’re going to know, do not need to learn it → “the recollection of
the soul”; knowledge is inherited from previous lives before us (Socrates)
● Aristotle: we are born with nothing and learn everything over time through experience
● Common themes between the two philosophers: influences of nature/nurture & interested in the
proper raising of children
○ Plato = discipline and self-control
○ Aristotle = different children should be raised according to their unique needs
● Rene Descartes: argues for the role of nature and development; mind is a part of the body that
naturally grows, similar to limbs; cognition as a “mental organ”
● Noam Chomsky: argues for nature; we are biologically predisposed to learn language (LAD)
● John Locke: argues for nurture, “blank slate” – we etch things onto our blank slate through
learning; argues that parents initially impose strict rules, but later grant freedom
● David Hume: argues for nurture; children learn through cause and effect
● 1800s and early 1900s beginning of empirical revolution; study negative outcomes of children
factory workers during industrial revolution
○ Charles Darwin drew parallels between human prenatal growth and other animals’
○ Kept a diary of his own child's development over time; systematic observations
● Sigmund Freud: behavior is motivated by innate, unconscious, instinctual drives
○ The type of drive changes over development and are characterized by universal stages
● Behaviorism: study only directly observable things (Skinner and Watson); no mental phenomena
“thoughts”, “concepts”, “beliefs”, “consciousness”... believed the had no solid explanation
, ○ Based off of Pavlov’s classical conditioning; nurture can overcome nature
○ Skinner’s operant conditioning = positive/negative reinforcement can be used to shape
behavior
● Watson’s Little Albert Study (1920): conditioned baby to be scared of rat through loud noise
association – fear generalized to other fuzzy things as well
● Behaviorism was a response to eugenics (Francis Galton) belief that the human race can be
improved by selecting for traits in population; coined the phrase “nature vs nurture”
● Cognitive Revolution: to explain behavior, we have to think about the mind and mental processes;
the mind is like a computer that processes information
● Jean Piaget = father of developmental psychology; founded the field of cognitive development
○ Studied nearly every aspect of child cognition (like a zoologist)
○ Invented simple and clever tasks to test his ideas; scientific study of development
● Development happens in stages – discontinuous development (challenged/not supported)
● Learning is a constructive and active process in which the child is a little scientist
● Leo Vygotsky: child in cultural context is unit of study; social environment and influences of the
outside world changes how we develop
○ Process of internalizing social and cultural information; mechanism = social interaction
● Modern psychology still deals w/ the question of nature vs nurture
Lecture 3 – 4/9/24
● Heredity: chromosomes contain genes that get turned on/off and each pair may have slightly
different versions of the same gene (allele) → each allele carries instructions for a specific
variation on a trait
● Alleles can be dominant or recessive, and homozygous or heterozygous
● Genetic diversity can occur through crossing over = process by which sections of DNA switch
from one chromosome to another; promotes variability
● Mutation = section of DNA is changed; spontaneous error
● Different environments can lead to different development
● Maple syrup urine disease: disorder related to a defective recessive genes; cannot metabolize
three branched-chain amino acids (urine smells like maple syrup); if caught early on, a special
diet can help avoid impairments
● Children are a source of their own development; seek surroundings to match their interests and
personalities
● Epigenetics: study of stable changes in gene expression that are mediated by the environment
○ Methylation – common epigenetic mechanism where molecules block transcription
● Heritability: statistical estimate of the proportion of the measured variance on a trait among
individuals in a given population that is attributable to genetic differences among individuals
○ Heritability only applies to a particular population living in a particular environment
Ecological Theories
● Ethology: study of a behavior within an evolutionary context (adaptive survival value)
● Imprinting = some species of birds follow mother during a critical period – biologically
predisposed
● Evolutionary psychology: play is an evolved platform for learning during period of immaturity
for most mammals
, ● Parental-investment theory = stresses the evolutionary basis of many aspects of parental behavior
benefit their offspring
○ Cinderella effect: child maltreatment are higher for stepparents than biological parents
● Bioecological model: environment is a “set of nested structures” -Urie Bronfenbrenner
○ Every level has an impact on development, but differ in how immediate their effects are
● Microsystem = immediate environment an individual personally experiences
● Mesosystem = inter-connections among various microsystems
● Exosystem = environmental settings that a person experiences indirectly (e.g. parent’s working
hours)
● Macrosystem = larger cultural and social context
● Chronosystem = historical changes that influences the other systems (e.g. remote learning during
pandemic)
● Gene/environment interaction example: himalayan rabbit – environment effects that expression of
genes for fur color (ice pack turned fur black)
● Behavior genetics: twin studies (monozygotic and dizygotic)
○ Comparing personality traits between identical twins and fraternal twins – environment
plays a role in influencing personality
○ Minnesota twin studies: extensive study of identical twins separated early in life
● Adoption studies allow us to see if children are more similar to adoptive parents (environment) or
biological parents (genetics)
● Molecular genetics: science that examines specific DNA sequences to identify mechanisms that
link genes and behavior
○ Genetic factor accounts for about 50% of the influence of socioeconomic status and
educational achievement
● Summary = genetics and environment interact to influence development
Lecture 4 – 4/11/24
● Early ideas about prenatal development:
1. Quantitative Change = “preformationism”; ‘spermists’ vs ‘ovists’
a. Present idea until the 1800s
2. Qualitative Change = epigenesis (Aristotle) cells multiply and differentiate
a. Not embraced until modern study of embryology
● REMINDER → due next wednesday 4/17 Pop Science Response 1
● Stem cells: cells that have not yet differentiated into specialized cells; flexible and powerful
regenerative tool
● Developmental process includes cell division, cell migration, cell differentiation, and finally cell
death
○ Cell death example – webbing between fingers and toes gradually dies
● Fetus is considered viable at 28 weeks (viability means they can sustain themselves outside the
womb)
● Prenatal Phases: zygote (1-2 weeks), embryo (2-8 weeks), fetus (9-38 weeks)
○ Zygote: fertilization, implantation, placenta formation
○ Embryo: layers of cells, neural tube, limbs, organs form
○ Fetus: movement, sensory abilities, rapid growth, brain development
