This document discusses the nature vs nurture debate regarding human behavior. It provides examples that support both nature and nurture influences. For nature, it discusses genetic influences on behaviors and conditions like language acquisition and schizophrenia. For nurture, it discusses studies showing environmental influences like Little Albert's learned fear response and the Stanford Prison Experiment. It also notes that behavior is often an interaction between innate traits and environmental responses, and provides applications of considering both nature and nurture in developing drug therapies or adapting environments.

1. Nature vs Nurture
Dr. D Raj kiran
Senior Resident
Dept of Psychiatry
KIMSRF

2. Learning objectives
 Nature versus Nurture controversy
 Sheldon’s body types
 Blood types and personality
 Delusions

3. Charles Darwin
“Through naturalselection,organismspassontheirgenesto
subsequentgenerations,certainabilitiesbecome inbuiltintothe
geneticcode. Somanyabilitiesthatdevelop inhumansare
biologicallybasedratherthanpurelyproducts oflearning”.

4. John B Watson
“Givemeadozen healthyinfants,wellformed, andmyownspecified
worldtobringthemupin,andI’llguaranteetotakeanyoneat
randomandtrainhimtobeanytypeofspecialistImightselect-
doctor, lawyer,artist,merchant-chief,and,yesevenbeggar-man
andthief,regardless ofhistalents,penchants,tendencies,abilities,
vocations,andraceofhisancestors”.

5. Nature
 Behaviour is caused by innate characteristics:
Physiological/ Biological characteristics.
 All behaviours are present from conception.
 Genes provide the blueprint for all behaviours; some
present from birth, others pre-programmed to emerge
with age.
 Is a developmental approach.

6. Nurture
 Behaviour is determined by the environment- the things
people teach, things they observe.
 Behaviour is the result of interactions with environment.
 Born an empty vessel- waiting to be filled up by
experiences gained from environmental interaction.
 Can become anything provided the environment is right.
 Behaviourist theories are nurture theories.

7. Nature vs Nurture
 Degree to which human behaviour is determined by
genetics/ biology or learned through interacting with
the environment.

8. Who created?
 Initial use of the Nature vs. Nurture Theory was
credited to psychologist Sir Francis Galton.
 Hippocrates described human behaviors as being
biological, the result of four different body fluid types
called humors.
 Blood
 Yellow bile
 Black bile
 Phlegm

9.  Later, Philosophers thought that people are born as
blank slates (i.e. “Tabula Rasa"), and that eventual
individual differences develop solely due to the result
of environmental influences.
 20th century psychologist John Watson shared a
similar perspective, events that take place during early
childhood have more influence on what kind of adults
we become compared to the effects of our genes.

10. Support for Nature
 Piaget- Children’s thought processes change at
predetermined age-related stages.
 Freud's theory of aggression
 Innate drive (called Thanatos). (Eros- pleasure drive)

11.  Language Acquisition- Chomsky maintained language
is the result of innate cognitive structures in the mind.
 Children are predisposed to make sounds and
understand grammar.
 Does not happen from birth but language skills develop
rapidly after a certain period of time.
 Language acquisition follows the same sequence in all
children, an inbuilt genetic mechanism is responsible.

12.  Genetic basis of Schizophrenia-
 Adoption studies: compared biological parents and siblings
and adoptive parents and siblings.
 Increased incidence in adopted children with a schizophrenic
biological parent.
 Twin studies: compared identical and non-identical twins.
 Higher rate for schizophrenia in identical (58%) than non
identical twins (12%).
 Conclusion Significant genetic input into the onset of
schizophrenia.

13. Support for Nurture
 Little Albert-
 Classical conditioning of fear- phobia acquisition.
 Provides evidence that the environment can be
manipulated to create a phobic response & behavioural
change.
 Zimbardo (1973) Stanford Prison Experiment
 24 participants - Randomly assigned to the role of
‘prisoner’ or ‘guard’.
 The behaviour of the ‘normal’ students was affected by
the assigned role- seemed to believe in their allocated
position.

14.  Bandura’s social learning theory-
 Aggression is a learned from the environment through
observation and imitation.
 Bobo doll experiment.
 Skinner-
 Believed that language is learnt from other people via
behavior shaping techniques.

15. Nature-Nurture interaction
 Behaviour is often a result of interaction between nature
and nurture.
 An individuals characteristics may elicit particular
responses in other people
 Temperament- how active, responsive or emotional an
infant is influenced in part determines their caregiver’s
responses.
 Gender: people tend to react differently to boys and girls
due to expectations of masculine and feminine
characteristics.

16.  Rutter and Rutter (1993) Aggression hostility –
 Described how aggressive children think and behave in
ways that lead other children to respond to them in a
hostile manner.
 This then reinforces the antisocial child’s view of the
world.
 Thus, aggressive children tend to experience aggressive
environments partly because they elicit aggressive
responses.

17.  Maguire et al. (2000)- Taxi driver study
 Structural MRI scans of the brains of London taxi drivers
compared with controls who did not drive taxis.
 Hippocampal volume correlated with the amount of time
spent as a taxi driver
 Posterior hippocampi of taxi drivers were significantly larger
relative to those of control subjects.
 It stores spatial representation of the environment and can
expand regionally in people with a high dependence on
navigational skills.

18. Applications
 Nature:
 Drug therapies can be developed to treat behavioural or
psychological problems that have a physiological origin
 Eg: SSRI’s can be used to treat depression
 Nurture:
 If behaviour is susceptible to environmental influences
we can consider to adapt our environment
 Eg: promote helping behaviour, enhance learning,
reduce aggression, decrease criminality etc.

19. Thank you