Nature and Nurture Flashcards
Key reading and lecture (30 cards)
What is Nature? with example
Argues humans are born with certain psychological traits that are inherited.
- Inherited (Heredity)
- biologically controlled
- innate, instinct
Example: Sir Francis Galton proposed the idea of mental inheritance. (father of behavioural genetic movement)
what is instinct using Descartes and Lorenz
Descartes - instincts as source of behaviour designed by god to make behaviour adaptable
Fixed action patterns: Instinct to enact certain specific behaviour, when view particular stimulus cue.
e.g., Dogs chasing cats
Lorenz - imprinting in geese:
Got imprinted by geese, as first thing they see when wake it they imprint (innate) and they imprinted on all sorts
If they don’t see anything, after 2 weeks then given object they don’t imprint
what is Nurture?
Suggests that personal experiences and the environment shape an individual’s behavior.
Environment
socio-economic
epigenetics (health, diet, stress, generations)
Example: John Locke’s “tabula rasa” theory, where experience molds behavior.
Imprinting
- Imprinting an instinct shaped by learning:
- Imprinting as special kind of learning
- Irreversible
- Characterised by “sensitive period”
- Imprinting is ‘innate’ (object of imprinting is not)
e.g., A clear example of an interaction between heredity and learning
what is a senstive period
Period during which experience / environment has strong influence or behaviour is most likely to be acquired
e.g., birds learning sings, language learning in humans
Biological constraints on learning:
Seligman’s biological preparedness - Mineka & Cook (1988)
Viewing an adult reacting in fear to snake = young lab-raised macaques learn fear response immediately
Viewing an adult reacting in fear to a flower does not cause infant to learn fear of flowers
Bio restraint (no fear of flower) but learnt fear of snake (learning)
MAOA gene and anti-social behaviour:
- Low activity variant of this gene correlates with expression of anti-social behaviour (criminality & violence)…
- …But relationship is mediated by environment: Criminality more likely in people with low-activity gene variant AND who were mistreated/abused as children
Anti-social behaviour more likely if have gene and environmental factor
Behaviour genetics aims
Aims to identify/disentangle role of genetics from environmental inputs to behaviour – understand the form of those interactions
- Not ‘genes for’ a behaviour
Do genes cause a behaviour
NOOOO
GPS – Genome-wide polygenic score (What is it)
Determines how much of a trait is down to genes and how much is down to environment
Behaviour genetics - Robert Plomin
Almost all psychological traits have some genetic-inherited component
- Intelligence; personality; emotion; psychopathology, etc.
Environment also important in expression of all (phenotype)
Not talking about one gene ‘for’ something
- Look at differences in massive amount of genetic material
found = being in same family (shared envio. doesnt make children more simular. most measures of enviroment include genetic component
two types of twins
- Monozygotic (identical) – same DNA
- Dizygotic (fraternal / non-identical) – share same amount of DNA as other siblings
sepration stuides
MZ twins raised apart (RA) – different environments:
- Now similarities must be down to shared genetics?…
- But – often not totally ’apart’ (e.g. different branch of same family)
- Already shared same environment in utero
- Adoptive families often selected for being similar, not randomly selected
Adopted studies
- Share DNA but not environment with biological parents/siblings
- Share environment but not DNA with adoptive parents/siblings
Can ask who they are more similar to – biological or adoptive family
Stronger correlation in IQ with biological parents (in some studies)
Other studies show working-class children raised in middle- or upper-class families show higher IQ than parents: - Environment has a role
Heritability statistic (H)
tells us how much variation in an observed trait is due to genetic variation, on average, within that population
- H of 50% = half of the variation in trait within the population is due to genetics, half due to something else (environment) - not 60% envio jst 40% down to genetics
- Genetic input is not deterministic
- Genes provide framework, environment fills in the details
- non predicitve
can we test genetic diffrences between a group?
NO we can only test within a group (only alter one thing at one time)
Key points
cannot explain behvaiour from one lense
immense web of causality for our actions from millions of years
‘cause’ of behaviour in one condition can create diffrent outcome in another
we need context and multiplicity of pespectives to undertsand behaviour
core issue in nature and nuture debate
The debate centers on what shapes human behavior and traits: innate biological factors (nature) or life experiences (nurture).
3 reasons why the debate is important
Wide Relevance: Impacts all aspects of psychology, shaping our understanding of identity.
Predictive Value: Helps in identifying strengths, weaknesses, and potential outcomes in early stages.
Mental Health: Facilitates early diagnosis of psychological issues
Plato, Aristole and Psamyik experiment on the debate
Plato: Believed knowledge is innate, emerging as the soul recollects past experiences.
Aristotle: Argued the mind is a “blank slate” at birth, shaped by the environment.
Psamtik I’s Experiment: An ancient test on language acquisition in isolated infants, though the results were inconclusive.
Dawin and Galtons (+eugentics def)
Charles Darwin: Emphasized that biological traits passed through generations may enhance survival, supporting the “nature” side.
Sir Francis Galton: Focused on mental inheritance and how family success can pass through generations.
eg: - Based in biographical data - people tend to have successful parents and successful children (success runs in families)
- Eugenics: Galton promoted the idea of improving human traits through genetic selection, but it led to discrimination.
one good thing about twin studies and one bad
Nature vs. Nurture: Twin studies support genetic inheritance in traits like intelligence.
Eugenics Controversy: Used to justify discrimination, suggesting certain genetic traits were more valuable than others.
watson and skinners view with chomskys critc
John Watson: Argued that behavior is shaped entirely by the environment, rejecting the idea of innate instincts.
- agressive traits in history because we see agression
- study obserable phenomia (habits)
Skinner’s Views: Focused on reinforcement and punishment but did not acknowledge genetic predispositions.
Chomsky’s Critique: Challenged behaviorism by highlighting the complexities of language acquisition, suggesting innate biological mechanisms play a role.
ethology
Ethologists: Studied instinctive behaviors in animals, such as fixed action patterns triggered by specific stimuli.
Example: Gulls pecking at red spots to receive food.
Learning and Instinct: Some behaviors blend innate instincts with learned experiences.
