PSYCH 1XX3 Development

development

gene-environment interactions across an individual's lifespan; the changes and continuities that occur within the individual between conception and death

maturation

biologically timed unfolding of changes within the individual according to that individual's genetic plan

learning

relatively permanent changes in our thoughts, behaviours and feelings as a result of our experiences. can be controlled but eventually become automatic i.e. avoiding touching a hot stove

what are the four methods of measuring abilities in infants?

habituation, event-related potentials, high-amplitude sucking method, the preference method

habituation

decrease in responsiveness to a stimuli following its repeated presentation; determining if the infant can tell if the stimulus has changed

how is habituation used to measure abilities in infants?

begins by repeatedly showing infant the same stimulus and measuring infant response rate (i.e. heart rate or where the infant is looking, etc.), after some time, interest decreases and response goes down, the stimulus is changed and if response increases the infant can detect the change

event-related potentials (ERP)

detecting how the infant's brain reacts to the stimulus

how is ERP used to measure abilities in infants?

a cap with array of electrodes is placed on the infant's scalp, if visual stimulus is presented there is expected change in the occipital lobe, if auditory stimulus is presented there is expected change in the temporal lobe, the cap can measure changes

what information does ERP and habituation provide?

sensory interactions (behavioural = habituation, neural = ERP)

high-amplitude sucking method

measuring if the infant likes the stimulus

how does the high-amplitude sucking method measure abilities in infants?

the baseline sucking rate is measured and a shaping procedure where the infant is given control over the stimuli takes place. if the infant increases the sucking rate the stimuli will remain, if the infant decreases or remains at the baseline sucking rate the stimuli will be removed.

the preference method

measuring which of two stimuli the infant likes more

how does the preference method measure abilities in infants?

infants are put into a looking chamber with two stimuli, researchers measure the direction the infant looks at to determine attention given to each stimuli. more attention = preferred

when is the preference method used?

after researchers determine if the infant can tell a difference between the two stimuli

what types of images do infants prefer looking at?

big patterns with black and white contrast, faces

competence-performance distinction

an individual may fail a task not because they lack those cognitive abilities but because they are unable to demonstrate those abilities (ex - preverbal infants)

longitudnal design

a developmental research design in which the same individuals are studied repeatedly over some subset of their lifespan

what are cons of longitudnal design?

very expensive and time consuming, selective attrition (when some people are more likely to drop out of a study than others, making non-representative our the original population), practice effects

cross-sectional design

a developmental research design in which individuals from different age groups are studied at the same point in time

what are the cons of a cross-sectional design?

cannot distinguish age effects from generational effects, cannot directly assess individual developmental change

zygote

sperm + egg cell

how many different genetic combinations can one parent produce?

8,000,000

monozygotic twins

identical twins, one zygote splits into two, genetically identical

dizygotic twins

different sperm and ovum, no more similar than regular siblings

how many autosome pairs do humans have?

22

how many pairs of sex chromosomes do humans have?

1

genotype

individual's inherited genes

phenotype

expression of an individual's genotype in terms of observable traits

what are the 4 patterns of genetic expression

simple dominant-recessive inheritance, polygenetic inheritance, codominance, sex-linked inheritance

simple dominant-recessive inheritance

a pattern of inheritance in which the expression of a trait is determined by a single pair of alleles

homozygous alleles

two identical alleles of a particular gene

heterozygous alleles

when someone has 2 different alleles of a particular gene (only dominant allele is expressed in phenotype, recessive allele is not expressed but is still heritable)

polygenetic inheritance

when the expression of a trait is determined by the inheritance of multiple genes i.e. eye colour

codominance

when the expression of a trait is determined by two dominant alleles

what is an example of a codominant gene?

ABO blood type gene, A and B are both codominant, O is recessive, when both A and B are present the blood type is AB

sex-linked inheritance

when the expression of a trait is determined by genes on the X/Y chromosome

why are more genes and disorders linked to the X chromosome?

the X chromosome is larger

who is more likely to be affected by sex-linked recessive gene disorders

males

why are males more likely to be affected by sex-linked recessive gene disorders

males only have one X chromosome so they will always present symptoms of a sex-linked recessive disorder on the X chromosome

who is affected by Y-linked disorders?

males

what do nuturists believe?

external factors alone ultimately influence development

who is a famous nuturist?

John B. Watson

what do naturists believe?

genes predetermine the path of development

canalization principle

within a species, genotype restricts the phenotype to a small number of possible developmental outcomes

what do all infants do the same regardless of cultural background?

babble

range of reaction principle

genotype establishes a range of possible phenotypes in response to different kinds of individual life experiences

how do canalization and range of reaction work together?

canalization restricts possible outcomes (determines the max and min) and range of reaction decides your specific phenotype

passive genotype/environmental correlations

the environment that parents choose to raise their kids was influenced by their own genes so it will likely compliment their child's genes

when do the passive genotype/environmental correlations impact us most?

early in life

evocative genotype/environmental correlations

the traits we inherit affect how others react and behave towards us

when do evocative genotype/environmental correlations influence us most?

throughout our lifespan

active genotype/environmental correlations

our genotypes influence the kinds of environment we seek

when do active genotype/environmental correlations influence us most?

influential more in adolescence and later in life

what is the IQ correlation between identical twins?

0.80

what is the IQ correlation between fraternal twins?

0.60

what is the IQ correlation between identical twins raised apart

0.72

what is IQ more likely impacted by?

genetics

critical period

a window of opportunity within an individual's development in which particular environmental stimulation is necessary in order to see permanent changes in specific abilities, since replaced with sensitive period

experience-expectant brain growth

our brains have evolved to expect a certain amount of environmental input, and with this input our brains develop normally

experience-dependent brain growth

our brains develop according to our own personal experiences

expectant

sufficient stimulation= normal development

dependent

unique stimulation = beyond normal development

sensitive period

developmental periods during which a specific type of learning takes place most easily (less rigid than critical periods)

quasi-experiment

similar to normal experimental design but lacks random assignment of individuals to groups; quasi-experiments cannot control for extraneous variables leading to confounding variables

normative

research that investigates how normally things change as an individual ages

analytic

research focused on the processes or variables that are responsible for the changes in abilities and needs from age to age

what is central to both normative and analytic questions?

age or the passage of time

cohort effect

disadvantage to cross-sectional design; differences in age groups may be due to generational differences and not differences in development

genome

complete set of instructions (genetic information) contained in every cell in an organism

dominant

the allele of one gene that is expressed over the second allele of the gene

recessive

only expressed if both alleles for the gene are recessive; a dominant allele will be expressed over a recessive allele

what does the master gene model of sex determination suggest?

the SRY gene, located on the 23rd chromosome, is chiefly responsible for determining sex

what does the cascade gene model suggest?

the SRY gene is just one of many genes that interact to produce the sex of an individual, both male and female genetic contributions are important for determining the biological sex of offspring

androgen insensitivity syndrome

when an individual is biologically male but is resistant to male hormones (androgens); this can affect male sex characteristics

when does the nervous system start developing?

21 days after conception

neural plate

key developmental component of the nervous system. composed of primitive neural tissue and eventually becomes the neural tube

neural tube

neural plate folds and closes to become a hollow structure known as the neural tube, which eventually leads to the development of the brain and spinal cord; lined with neural stem cells that give rise to all cells of the nervous system

when parts of the brain are visible after about 28 days after conception?

basic brain regions of the forebrain, midbrain and hindbrain

when does the brain begin to look distinctly human?

100 days after conception

what is formed after 210 days (~7 months) after conception?

the sulci and gyri characteristics of the adult mammalian brain

when do the number of synapses begin to decrease

from 1 year to 10 years of age

synaptic pruning

changes in neural structures that results in a reduction in the number of synapses

why is synaptic pruning considered adaptive?

the brain first produces an overabundance of synapses, then prunes away the unnecessary or incorrect ones to ensure that only the strongest and most useful persist

occular dominance columns

columns of neurons in the visual cortex that respond preferentially to information (visual signals) from one eye or the other

amblyopia

"lazy eye", loss of visual acuity in an otherwise healthy eye

what is one type of treatment used to avoid long-term visual problems?

remove the cataract as early as possible and cover the stronger eye with a patch. "patching" works because the eyes compete with each other for cortical space in the visual cortex, covering the stronger eye reduces competition and allows the formally deprived eye to strengthen its connections to ocular dominance columns in the visual cortex

neurogenesis

development and growth of neurons

how do you promote plasticity in your brain?

giving your brain relevant things to do i.e. physical exercise

what did Piaget underestimate?

the cognitive abilities of infants

what do infants seem to understand innately?

abstract concepts and physical properties (i.e. infants were surprised to see physically impossible things like a car passing through a solid object)

what is reasoning in adolescence focused on?

the self

fluid intelligence

involved with abstract thinking and quick reasoning and generally declines with age (solving puzzles and critical thinking)

crystallized intelligence

individual's accumulated knowledge, may increase with age (life advice, math formulas, etc)

what do we lose as we age?

memory and processing speed

what do we gain as we age?

verbal abilities

what types of memory do younger adults have better than older adults?

working memory and episodic memory

what types of memory shows little to no decline as we age?

implicit memory

what does memory performance of older adults depend on?

what they are asked to recall. when asked to recall a list of meaningless syllables or unimportant events they make more recall errors than younger adults, but if the information is meaningful, recall is comparable to younger adults.

was there any significant difference in the likelihood for couples to get pregnant after adopting or not adopting a child?

no, the perceived difference was due to confirmation bias

marshmallow study

famous longitudnal study, high resistance vs. low resistance behaviour believed to be locked in by age 4, children who showed high restraint had better emotional regulation, test performance and working memory, children who showed low restraint had higher drug use, divorce rates and BMI