The Nature Nurture Debate or The heredity environment issue

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The Nature Nurture Debate(or The heredity
environment issue)

• The nature nurture debate is older than
  psychology itself and is still as vigorous as
  ever.
• Nativist (Nature) view-
• individuals are born with an inherited
  blueprint- Genetic inheritance, neurochemcical
  and hormonal influences, brain activity.
  Behaviours not present at birth will develop
  through the process of maturation.

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• Empiricist (Nurture) View-
• an individuals mind at birth is like a blank
  slate (tabula rasa) on which the environment
  (experience) will write. Behaviour is acquired.
  Within their physical limitations an individual
  can do /be anything, provided the environment is
  right.

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Questions asked concerning the nature nurture
debate

• Is it Nature or Nurture that is responsible for a
  particular behaviour?
• An illogical question, as one can not exist
  without the other, both are needed for a person
  to exist, so both must exert an influence.
  (Anastasi, 1958).
• How much of a particular behaviour is determined
  by nature and how much by nurture?
• (e.g. 80Na 20Nu 100 behaviour ?)
• Still an illogical question, as the 80 Na has to
  exert its influence through an environment and
  the 20 Nu has to express itself through an
  organism. Both are involved in the expression of
  the behaviour.

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In what way do Nature and Nurture influence
behaviour?

• A more useful question. It assumes that
• -genetics and the environment interact. (Nature
  x Nurture behaviour, like a rectangle length x
  width area of rectangle).
• Different environments acting on same genetics
  pattern may result in different behaviours.
• Same environment acting on different genetic
  pattern will result in different behaviours.
• Genes never determine behaviour directly , only
  through the environment.
• Environment only affects behaviour via the
  genetic make up of the individual.

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• This last question is the one that concerns most
  psychologists today. In what way do nature and
  nurture interact and how do changes in one affect
  the influences of the other?
• What is actually meant by heredity and
  environment? They are not easy to define.
• Heredity-
• Anastasi (1958) suggests that hereditys
  influence on the individual operates along a
  continuum on indirectness, at one end of the
  extreme the influence is
• least indirect(most direct) e.g. Genetic
  conditions that cannot be treated
• in the middle e.g. Hereditary defects that can be
  treated, predisposition to develop a condition if
  environmental conditions are suitable
• and the other end most indirect (least direct)
  e.g. Social influence such as stereotypes that
  prevent a person from fulfilling their potential
  girls not developing technical skills.

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Environment-

• Lerner(1986) said we should think of the
  environment as having different levels.
• Inner biological level
• Mothers physical state during pregnancy
• Individual Psychological level
• Mothers psychological state during pregnancy
• Physical environmental level
• Post birth experiences
• Sociocultural historical level
• When, where child is born current state of
  scientific knowledge, health care education.

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• Anastasi (1958) suggested that the environment
  can be explained as on a continuum and can exert
  different degrees of influence on the individual.
  The effects are of two different types-
• Organic effects
• Broad effects
• (Physiological changes through damage,
  enrichment, diseases e.g. polio, alcohol abuse)
• Narrow effects
• (Short term diseases such as chicken pox)

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• Stimulative effects-
• Broad effects
• (Social class, lifestyle, wealth, expectations,
  opportunities)
• Narrow effects
• (Short term experiences such as the kind of
  school attended)

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• Constructivism is an alternative view of the
  environment. It suggests that people contribute
  to the construction of their own environments,
  they shape their own environments by the way they
  respond to the environment. It is suggested that
  the different biological or behavioural
  characteristics of individuals will elicit
  particular responses from others
• E.g. a contented baby
• more likely to elicit a positive response from
  its caregiver than a difficult baby.
• Gender differences -
• elicit different responses as does the
  aggressiveness of an individual.

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• As is illustrated above environment and heredity
  are not straightforward to define. There are also
  an infinite number of different environments and
  an estimated 70 trillion potential genotypes.
  However, although a vast area to study, it is
  still possible to consider the question How do
  nature nurture interact?

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• Anastasi (1958) and others use the concept of
• norm of reaction.
• Genotype sets upper and lower limits for
  development.
• There are a number of potential outcomes within
  these limits the norm of reaction which
  outcome will occur will depend on the interaction
  of the genes with the environment.
• Recent developments suggest
• that genetic endowment is more flexible than
  previously thought, there for rigid upper and
  lower limits to development may not exist as
  suggested by the norm of reaction.
• It is accepted that the norm of reaction as an
  explanation of nature nurture may be limited.

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• Psychologists today accept that the two are
  virtually inseparable and that they interact with
  each other along a continuum. It follows then
  that
• No two people (even identical twins) are alike
• It is pointless looking for general laws of
  behaviour that are given in environmental terms
  (e.g. behaviourism), but it makes more sense to
  look for individual laws that can explain an
  individuals unique developmental pattern.
• Individuals are likely to be influenced
  prenatally, socially, culturally, domestically,
  educationally e.t.c in different ways. The norm
  of reaction suggests that each individual needs a
  uniquely tailored environment to fulfil their
  potential - think about the implications of this
  (e.g. in education).

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• Going back to the nature nurture extremes,
  which areas in psychology have traditionally
  taken which view? Here are a few examples from
  the topice you have studied.
• Sex role behaviour-
• Biopsychologists gender is the result of
  genetic hormonal influences
• Learning theory gender is socially constructed
  and reinforced
• Abnormality-
• Biomedical approach genetic and neurochemical
  causes of mental disorders
• The role of the environment in the development of
  disorders such as in anorexia, post-traumatic
  stress disorder and phobias.

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• Examples in psychology where an interactionist
  (nature and nurture are both involved) approach
  has been taken-
• Cognitive development Piagets theory
  biological maturation, innate scheme interacting
  with the environment to develop childs cognitive
  abilities.
• Abnormality the concept of a predisposition to
  develop a disorder when the environmental
  conditions are right.
• Sex-role behaviours biosocial approach
  physical sex and innate temperament of a new born
  baby elicits sex typing behaviour from the people
  around it, leading to a self fulfilling prophecy
  in terms of gender identity.