Studying Development Scientifically Flashcards
what are the 3 key aims of developmental psychology?
- charting the course of development
- predicting outcomes
- identifying causes of development
what conditions for causality did menard (2002) identify?
- covariation
- covariation must not be spurious
- causal factors must not precede outcomes
necessary causal factors
must be present for the outcome to occur
sufficient causal factors
are by themselves enough to cause an outcome to occur
what must things be in order to cause development?
both necessary and sufficient
cross-sectional research
conducted at a single point in time
benefits of cross-sectional research
it provides valuable information on the course of development, without requiring any manipulation
limitations of cross-sectional research
does not provide definitive evidence towards developmental theories as:
- does not explain within-person change
- cohort and age effects
- no evidence of temporal ordering of cause-and-effect
longitudinal research
measures the same individuals at more than one point
benefits of longitudinal research
- studies the course of development to see within-person change
- can look at predictors of developmental outcomes
when are longitudinal studies appropriate?
- for within-person change
- focusing on the stability of individual differences
- studying causes of development
prospective panel
following development across time
retrospective panel
tracing back development
benefits of panel designs
able to provide evidence for developmental change by viewing within-person change and avoiding cohort effects
limitations of panel designs
- can be confounded by period effects
- retrospective panel designs can suffer from recall bias and selection effects, leading to an unreliable temporal order
multiple-cohort designs
follow different groups across time simultaneously
benefits of multiple-cohort designs
- rule out the possibility of cohort and period effects
- provide the strongest evidence for developmental change
intervention studies
a form of longitudinal design where two different groups are randomly allocated after the pre-test
benefits of intervention studies
- able to establish definite causal connections
- rule out spuriousness through control groups
panel and multiple-cohort studies
+ can establish whether a connection naturally occurs
- cannot make causal connections
intervention studies
+ establish definite causal connections
- these connections may not exist in real life
what types of studies are needed to establish a developmental cause?
both panel and multiple-cohort studies & intervention studies
what do intervention studies explain?
which variables are sufficient to cause a developmental outcome
what do cohort studies indicate?
whether the variable is necessary within natural development
reasons why intervention studies cannot only be used
- ethical limitations
- connections may not occur naturally
- period effects
what is the aim of behaviour genetics?
to understand the genetic and environmental origins of individual differences
what are the 2 types of behaviour genetics?
quantitative genetics and molecular genetics
quantitative genetics
estimate the genetic and environmental influence on individual differences in the populaton
molecular genetics
identify specific DNA variants and genes to different phenotypes and behaviours
what do 1% of varying genes in DNA account for?
all individual differences
monozygotic twins share ____ of their segregating genes
100%
dizygotic twins share ____ of their segregating genes
50%
full siblings share ____ of their segregating genes
50%
half siblings share ____ of their segregating genes
25%
adopted parents and their children share ____ of their segregating genes
0%
biological parents and their children share ____ of their segregating genes
50%
what are referred to as ‘natural biological experiments’?
twin studies, which are used to compare MZ twins to DZ twins on particular measures
if MZ twins are more similar, this suggests that this trait is heritable
heritability
the proportion of variance between individuals that can be explained by inherited DNA differences
addictive genetic effect
heritability estimate
common environment
non-genetic influence within the household
non-shared environment
unique experiences to the individual
what do adoption studies look at?
the relative influence of genes and environment on child outcomes, using non-adoptive and adoptive designs
what assumptions do genetically sensitive research designs rely on?
twins being representative of the wider population, which is not true:
- at higher risk of disability and lower birth rate
- more likely to be born to older parents in high socioeconomic backgrounds
- ineffective if children have had life experience with their biological parents
genomics
the studying of measuring DNA differences
what are genes made up of?
3 million base pairs (ATCG)
what are most human behaviours described as?
polygenic, meaning that multiple genes influence particular outcomes
what are polygenic scores correlated to?
different phenotypes, e.g., intelligence, autism
