Psychology of Human Development
Exam 1 Study Guide
*Our first exam is scheduled for Thursday February 8th and will consist of 40 multiple choice and 10 fill in the blank. For the fill in the blank questions, our professor sent out a list of possible keywords which are found below with a definition and example of each. REMINDER there will not be a word bank on the exam but if you know the following words and the information provided then the fill in the bank should be easy points �!!
Theory: a set of concepts and propositions designed to organize, describe and explain a set of observations. Ex- Children model aggressive behavior that they see on TV (this predicts that children who see aggression on TV will act aggressively)
Hypothesis: A theory-based prediction about what will hold true if we observe a phenomenon. Ex- children who watch TV show aggressive behavior
Independent variable- The variable being changed, Ex- Amount of caffeine consumed before a test
Dependent variable- The variable being measured, Ex- Performance of the test
Correlation- A mutual relationship or connection between two or more things, measured with a correlation coefficient
Cohort effect- People of different ages were born in different times, may differ in ways other than age. Ex- A 20-year-old born in 1998 compared to an 85-year-old born during the Great depression have different experiences.
Longitudinal design- each participant is tested at a number of ages, follow the same individuals to see how they changed over time.
Cross-sectional design- different aged groups are tested at same time If you want to learn more check out What is verbal reports?
Sequential design-combination of cross sectional and longitudinal designs, Follow one group of participants longitudinally If you want to learn more check out What is a longitudinal fissure?
Mitosis- Process in which a cell duplicates its chromosomes and then divides into two genetically identical daughter cells
Meiosis- the process in which a germ cell divides, producing sperm or ova, each containing half of the parent cell’s original complement of chromosomes.
Genotype-the genetic makeup of an individual organism
Phenotype- The way a person’s genotype is expressed in physical characteristics, ex- hair color, eye color, height
Ultrasound- method of examining physical organs by scanning them with sound waves, Ex- scanning the womb to create a visual outline of the fetus to detect any abnormalities or gender
Amniocentesis- process of sampling amniotic fluid. A long needle is inserted into mother’s belly button and can test for any genetic factor
Chorionic villus sampling- Process of taking sample projections from the membrane surrounding the fetus and is faster than amniocentesis.
Concordance- likelihood that one person in a pair has a trait if the other person has it, Ex- identical twins vs fraternal twin traits. Schizophrenia is one twin results in 40% likelihood in the other whereas fraternal twins is 17%. We also discuss several other topics like What is the definition of epithelial?
Shared environmental influences- experiences that individuals living in the same home environment share and that work to make them similar
Non-shared environmental influences- variability among individuals with identical genetics and home environments, different experiences cause differences between the individuals
Gene-environment interaction- effects of genetics are dependent upon the environment in which you are raised. Ex- There is a strong genetic influence on height but in a deprived environment people with high and low potential end up being the same height
Gene-environment correlation- One’s genetics influence the environment in which one is raised
Zygote- name for a fertilized egg, formed at conception from the union of sperm and egg
Blastocyst- a hollow sphere of about 100 to 150 cells that the zygote forms by rapid cell division as it moves through the fallopian tube
Embryo- name for human offspring from the weeks 2-8 after fertilization Fetus- a name for human offspring beyond 8 weeks after fertilization We also discuss several other topics like What is hydrogen bond?
Placenta- an organ formed to provide nourishment of the unborn child and the elimination of it s metabolic wastes. Allows exchange between mother and child’s blood and protects from an immune response against baby.
Amnion-membrane that forms around the embryo
Teratogen-environmental agents that can lead to harm in a developing organism, Ex- alcohol, drugs, nicotine
Critical period- a defined period in the development of an organism when it is particularly sensitive to certain environmental influences, outside this period the same influences will have far less effect, Ex- language development within the first few years of lifeIf you want to learn more check out What is a working distance?
Apgar scale- how to measure if a baby is okay or needs special care, (>= 7 is normal)
Plasticity- the ability for nerve cells to change though experiences such as learning Myelin- fatty substance that insulates a neuron
Cephalocaudal principle- the principle that growth proceeds from the head to the tail
Proximodistal principle-the principle that growth proceeds from the center of the body to the extremities
Orthogenetic principle- the principle that development proceeds from global and undifferentiated states towards more differentiated and integrated patterns of response
Pincer grasp- a grasp in which the thumb is used in opposition to the fingers, enabling an infant to become more dexterous at liftin and manipulating objects.
Development: Systematic changes and continuities in the individual that occur between conception and death.
What causes Development?
1. Maturation- changes dictated by genetic programming
2. Learning- changes dependent upon interactions with the environment Methods of Testing
#1 Behavioral observation- observe the children on the playground and keep track of aggressive behavior. There are two types of behavioral observation. We also discuss several other topics like What is unpriming?
a.) Naturalistic observation- everyday environment
b.) Structured observation- set up an environment for the children, a lab setting. An example is Bandura’s Bobo doll experiment
Limitations of Behavioral Observation
1.) Observer influence- may act differently when they know they are being watched. Solution? The use of an adaptation period can help this by letting the child get used to the observer or have the observation be conducted by people the child already knows
2.) Observer bias- Interpret behavior to be consistent with one’s theory. Solution? Blind scoring helps because the observers are not aware of what is supposed
to happen. The ideal situation is “double blind”. For example, an experiment where there is a real drug vs a Placebo.
#2 Verbal Reports
Ex: Self reports, interviews, and questionnaires.
Participants provide information about their thoughts, feelings and past experiences. For example, if someone were to ask “How many times does your child watch an aggressive act on tv?”
Two types of Interviews
a.) Clinical interviews- different for each person, the interviewer can change the question based on the previous response.
b.) Structural Interview- everybody gets the same questions, can make comparisons because everyone was treated the same.
*Limitation because may not be accurate. Ex. “How often do you zone out while driving?” (Not a specific answer)
#3 Physiological Measurements
∙ fMRI- involves putting a person’s head in a magnetic field, can measure where there is blood flow in the brain
∙ PET- same thing as fMRI, measures blood flow but does so by injecting a radioactive tracer into blood
∙ EEG- putting a cap full of electrical sensors on a head, measures electrical activity. Faster than the others, Limited spatial resolution and don’t know exactly where activity is occurring
∙ Heart rate- heart rate activity, for instance if a child is scared by a stimulus
∙ Skin conductance- lie detectors, measures the sweat on the skin, if there is an emotional response to a question then the sweat will increase. Not 100% reliable
1.) Correlational Design- most straightforward, measures two variable to see if they relate and to see if there is a correlation. A correlation coefficient is used and varies from -1 to 1. If there is no relationship found, then the correlation coefficient is 0. The sign reflects direction of relationship where as absolute value reflects degree of relationship/strength.
0 1 2 3 4 5 6 7 8
20 15 10 5
0 1 2 3 4 5 6 7 8 Positive correlation
Ex. Negative correlation
*You’re not attempting to change or influence a participant’s performance on either variable, just measuring to see if there is a relationship
∙ Cannot infer cause and effect relationship
∙ Don’t know which variable is cause and which is effect
∙ Third variable effect- may infer two variables have a casual relationship when there is an actual 3rd variable involved (ex: Pellagra disease. Researchers found that houses that had indoor housing sewage disposal didn’t have pellagra disease compared to those who used outhouses. However, the third variable involved was diet. People who were able to afford high protein and high-quality food did not obtain the disease. (3rd variable= socioeconomic status)
∙ Directly manipulate the independent variable, the variable expected to cause changes in the second. IV= exposure to drug DV= prevalence of disease
∙ Groups must be equal prior to manipulation of IV to infer cause and effect, typically achieved by random assignment to groups
Problem? Not always ethical, ex: smoking causes lung cancer, it would be unethical to put babies in a room full of cigarette smoke to prove this. This is why animals are
often times used for experimental designs because when combined with correlational experiments we can develop a conclusion.
∙ Natural situation in which two groups seem to differ only on variable of interest
∙ Ex: cholera disease, researchers thought that it was spread through exposure. There were two districts in London that were equally similar except how they received their water. One received it upstream and one downstream. Researchers found that upstream had less cholera than downstream
∙ Can use this design because even though the experiment could be deemed unethical, its already happening in the world
∙ Also called natural experiment
∙ Cannot be sure that groups differ on no other variables
Developmental Research Designs- Human development
1.) Cross sectional (most widely used)
∙ Different aged groups are tested at same time
∙ Weakness- does not allow on to study changes in an individual, also the cohort effect (people of different ages were born in different times. May differ in ways other than age). Ex: A 20-year-old born in 1998 compared to an 85 year old who was born into the Great depression.
2.) Longitudinal design
∙ Each participant is tested at a number of ages, follow the same individuals to see how they changed over time.
∙ Cohort effect is decreased
∙ Weakness- can require a long time to complete the study. Practice effects (participants may learn from testing) for example students who take the ACT and SAT normally score better the second time not because they are smarter but because they learned HOW to take the test. Participant morality (participants who drop out may differ from those who remain) this could effect the statistical data from the study. And finally, results from one cohort may not generalize. For example, the obesity epidemic. The average body weight growth charts have changed over the years.
3.) Sequential design- combination of cross sectional and longitudinal designs Chapter 2
Key development issues
1.) Nature vs Nurture- nature theorists propose that development is driven by a maturational program contained within one’s DNA whereas nurture theorists propose that development involves changes in response to environmental events
2.) Activity vs. Passivity- Passivity theorists propose that development is shaped by environmental and genetic factors beyond one’s control. Ex: The behaviorists view point believe you could make a child into anything due to the environment. Activity theorists propose that people select and shape their environments in order to influence their own development. Ex: we chose to stay in school longer than we had to in order to better shape our future.
3.) Continuity vs Discontinuity- Continuity theorists propose that development involves gradually expanding the same structures and skills that were present at birth. Ex: babies can see at birth but develop better eyesight over time. Discontinuity theorists propose that development involves dramatic reorganizations in structures or skills. Ex: butterfly cycle from a larvae to a butterfly.
Stage theory: a series of qualitatively different forms or ways of thinking, basically means that we possess skills now that were not even possible when we were young.
4.) Universality vs context-specificity- Universality is when people all go through the same set of developments and context specificity is the idea that development can follow different paths depending upon the circumstances of development
Chapter 3 “Genetics”
Chromosomes: stores genetic information that we obtain from parents. Total of 46 in every cell
DNA- chemical substance that makes up chromosomes and can reproduce through mitosis
Gene- segment of DNA that codes for a protein, we have about 20,000 genes Genetics and Heredity
∙ Sperm and egg each have 23 chromosomes
∙ Created through process of meiosis
∙ They combine to form zygote with 23 pairs of chromosomes
∙ Each child receives just one of 2 chromosomes in each pair from each parent (2^23 possibilities)
∙ Crossing over occurs which is when the ends of a chromosomes switch positions before assorting into sex cells
∙ Identical twins- single fertilized egg (zygote) splits in 2 individuals after conception. They are genetically identical
∙ Fraternal twins- two different eggs fertilized by two different sperm. Therefore they are no more similar than ordinary siblings
Genetic Counseling and Testing
Diagnostic procedures after conception
1. Ultrasound- No risk, sound waves reflected off uterus, can get a good estimate of due date, can see if there are any abnormalities
2. Maternal blood sampling- no risk, test fetal blood cells in mother’s bloodstream
3. Amniocentesis- some risk, sample amniotic fluid. Long needle inserted into mother’s belly button. Downside is it takes a couple of weeks for information, cannot do it until around 12 weeks. Can test for any genetic factor
4. Chronic Villus sampling- sample projections from the membrane surrounding the fetus. Advantage is that you can do it early (8 weeks). You get more genetic material, so it is faster than amniocentesis. Some risk and is a rare procedure.
Examines the extent to which a trait is influenced by genetics and environment. Heritability: proportion of variation in a trait that can be linked to genetic differences Two measures of heritability
1. Concordance- likelihood that one person In a pair has a trait if the other person has it. “Either or traits”. Ex: Identical twins vs fraternal twins traits. Schizophrenia in one twin results in 40% likelihood in the other whereas fraternal twins is 17%
2. Correlation- degree of similarity on a trait between people with similar genetics. Ex: if one twin’s IQ score is above average its likely the other identical twin’s score is too
Causes of Variability on a trait
1. Genetics- greater similarity on a trait by people with higher genetic similarity 2. Shared environmental influence
3. Non-shared environmental influences- variability among individuals with identical genetics and home environment, different experiences cause differences
Do we get a trait from our environment? Genetics? Both?
∙ Effects of genetics are dependent upon the environment in which you are raised
∙ Ex: strong genetic influence on height. But in a deprived environment people with high and low potential end up being the same height. Whereas in an enriched environment your genetic potential will be expressed
∙ Genetics and environment work together
*One’s genetics influence the environment in which one is raised
1. Passive correlations- Parents provide an environment consistent with their genetics. We don’t have control over genetics or environment because parents give both to us
2. Evocative correlation- the child becomes more active in shaping environment. Ex: outgoing child, due to genes, will most likely be put into an environment that compliments this
3. Active correlation- people seek out environments that match their genetics abilities. Ex: college students choose to stay in school beyond the time that they have to
Stages of Prenatal development
1. Germinal Period (shortest)
∙ 0-2 weeks after fertilization
∙ Fertilized egg=zygote
∙ 50% of fertilized eggs attach or miscarry
2. Embryonic Period
∙ 2-8 weeks after fertilization
∙ Amnion= membrane that forms around embryo
∙ Amniotic fluid= protects organism from external impact, cushions embryo
∙ Chorion= sends hair-like projections to uterine wall for nourishment ∙ Placenta= organ that allows exchanges between mother’s and embryo’s blood. Protects from an immune response against baby ∙ Umbilical cord= connects embryo to placenta
3.) Fetal Period
∙ 8 weeks after fertilization until birth (longest period)
∙ The baby is now known as a fetus
∙ This period is divided into trimesters
a) First trimester (3rd month)
- The nervous system starts to connect with the muscles
- The fetus begins to kick, suck thumb, but is too small to feel - External genitals form and you might be able to tell on an
b.) Second trimester (4-6 months)
- Movement can be felt by mother
- Most neurons are in place by 24 weeks
- The fetus is now 2-3 pounds
c.) Third trimester (7-9 months)
- The fetus is viable between 22-26 weeks
- Gains 5 lbs of weight during 3rd trimester
- Brain enlarges because of an increase in supporting cells
- Fetus becomes top heavy, turns upside down
- In breech: when fetus does not turn upside down, greater likelihood the umbilical cord will get pinched and stop flow of oxygen to fetus
Influences of Maternal Health
- Rubella (German form of measles) causes heart defects, mental retardation
- Syphilis (STD) can lead to mental retardation or blindness. Doctors can treat if identified in time.
- HIV, can be passed to children in 3 ways
a.) Through mixing of blood to placenta (rare)
b.) During childbirth, baby might be exposed
c.) Through breastfeeding- women in this situation are advised to use formula and not breastfeed
- Malnourishment during 1st trimester can cause miscarriage or deformities
- During the 3rd trimester, malnourishment can cause low brain weight - Mother should gain at least 25-35 lbs during pregnancy
- Directs mother’s blood to heart, muscles, and brain for a fight or flight response rather than to the uterus
- Stress is associated with miscarriage, prematurity, and low birth weight - Extreme stress such as fear for life ex: WWII mothers living in bomb shelters
- Increase in chromosomal abnormalities with age which can lead to miscarriage
- Women 35 and above have a higher risk of Down Syndrome
- Amniocentesis is routinely performed for mothers over 35
- Teen mothers often have complications due to poor prenatal care rather than physical readiness to have children
Teratogens: Environmental factors that can affect pregnancy
1.) Thalidomide- a drug used to help morning sickness. If a mother took thalidomide in 4-6 weeks of pregnancy, then the limbs of the fetus would not be fully developed or not developed at all
2.) Alcohol- fetal alcohol syndrome can occur and cause mental retardation. Can also cause facial effects that are associated with extreme alcohol use. Fetal alcohol effects are a less dramatic form than the syndrome
3.) Nicotine- higher rate of women using nicotine, one of the most addictive substances. The most common effect is low birth weight. Can lead to hyperactivity in child
4.) Over the counter prescriptions and illegal drugs- Ex: antidepressants and Aspirin. Aspirin is associated with low birth rate and slowed motor development. Illegal drugs are highly addictive, and the baby becomes addicted and goes through withdrawal when born.
5.) Radiation- Ex: Hiroshima bombing. Any pregnant women within a mile miscarries and those women who were a couple miles farther gave birth to a child with deformities.
6.) Pollution- such as lead, older paint, and mercury which is found in fish
Four rules regarding teratogens
1. Effects of teratogens are worst during critical period in which an impacted organ system is developing
2. Susceptibility is determined by the genetic makeup of mother and child 3. The higher the exposure, the higher the risk
4. Effects often depend on the quality of the prenatal and postnatal development
∙ Oxygen deprivation (anoxia)
- Puts baby at risk if more than 3 minutes
- Breech delivery: umbilical cord can get pinched
- Can deliver by sea section
∙ Rh incompatibility: mother can develop antibodies to baby’s blood cell - Becomes a problem if a mother is Rh – and father is Rh +
- A vaccination can be given to avoid the development of the antibodies ∙ Birth Weight is low (less than 5 ½ lbs)
- Associated with greater risk of death, sensory and cognitive defects. Two types of babies with low birth weight.
1.) Preterm- delivered early, may develop normally if given good postnatal environment
2.) Small for date- baby is on time but small; may be indicative for exposure to risk factors during pregnancy such as drug and alcohol abuse
Apgar scale (>=7 is normal) – this is a way to measure if the baby is okay or needs special care. Calculated by adding together different points of each category. Things that are measured are…
1.) Heart rate- high heart rate is normal
3.) Reflexes- reacts to a light shining
4.) Muscles- strong movements are healthy
5.) Color- pink means good blood flow
Newborn Survival reflexes
3.) Pupillary- pupils constrict to bright light
4.) Rooting- turn head toward brushed check, helps in breastfeeding 5.) Sucking- suck on objects placed in mouth
7.) Moro- embracing motion when dropped or startled, ex: Gorilla babies are grabbing mother’s stomach while the walk
8.) Stepping- lift feet in alternation when they touch the ground, however lose this reflex around 6 months
9.) Swimming- flap arms and legs in water, survival instinct and with stay afloat long enough to be saved
10.) Grasping- grasp object placed in palm, eventually replaced by a voluntary grasp, learn to do it when they want to
11.) Babinski- fan and curl toes when foot is touched, trying to grab something with feet.
*Our Professor will finish up Chapter 5 on Tuesday so whatever he covers during that lecture will not be included in this study guide. GOODLUCK!!!!!! And don’t forget a blue scantron.� �