SIVYER PSYCHOLOGY

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NATURE VERSUS NURTURE

AQA SPECIFICATION:

NATURE-NURTURE DEBATE

  • THE RELATIVE IMPORTANCE OF HEREDITY AND ENVIRONMENT IN DETERMINING BEHAVIOUR

  • THE INTERACTIONIST APPROACH.

A01 CONTENT

  • The debate about the relative importance of heredity and environment in determining behaviour.

  • The nature side of the debate assumes heredity is more important

  • The nurture side of the debate assumes environment and experience are more important

  • Nature aspect is rooted in the nativist theory that knowledge/abilities are innate

  • Nurture is rooted in the empiricist theory that knowledge derives from learning – Locke’s view of the mind as a ‘tabula rasa’ or blank slate on which experiences are written

THE NATURE-NURTURE DEBATE

Nature versus nurture is a long-standing debate in the social sciences about the balance between two competing factors that determine fate: genetics (nature) and environment (nurture). The expression "nature and nurture" in English has been in use since at least the Elizabethan period and goes back to medieval French

THE NATURE DEBATE

Nature assumes that a person:

The nature side of the debate believes that the relationship between mind and body is caused by biological mechanisms such as:

  1. Behaviour has been shaped by natural selection (evolutionary psychology). Natural selection shapes the hardware of the brain whilst neuroscience is the study of the hardware.

  2. The central and peripheral nervous system, including neural mechanisms such as neurotransmitters and brain structure and localisation, including brain plasticity.

  3. The endocrine system and hormones, e.g., the influence of testosterone, oestrogen, oxytocin etc on behaviour.

  4. Diseases and accidents, For example, accidents that cause head injuries such as skateboarding, bike, falls and car accidents. Diseases such as Encephelistus, Syphillus, Parkinson’s disease, dementia, MS and motor neuron disease.

  5. The influence of heredity and genetics on behaviour. Inherited traits are carried in your genes. Parents pass on these genes to their children, who then pass them on to their future children, and so on. This genetic information is carried in the form of DNA, which stands for ‘deoxyribonucleic acid’. The average person has about 9 million kilometres of DNA in their body. If you unravelled them all and placed them end to end, they would stretch to the sun and back several times over! About 99.9% of the DNA of every human being on the planet is exactly the same. Only 0.1% makes us the unique individuals we can see in the world all around us. Some examples of inherited characteristics.

  • Eye colour

  • Hair colour and texture

  • Skin tone

  • Blood group (A, B, AB, O)

  • Freckles

  • Colour blindness

  • Dominant hand

  • Dimples

  • Earlobe attachment

  • Hairline shape

There are probably hundreds if not thousands of other inherited characteristics which we don’t know about yet because they’re hidden in our genetic code or DNA.

These facts have led many to speculate as to whether psychological characteristics such as behavioural tendencies, personality attributes, and mental abilities are also “wired in” before we are even born

The nature side of the debate believes that individuals do not have control over their behaviour and they are not responsible for their own actions.

NATIVISTS (Extreme Nature Position)

Those who adopt an extreme hereditary position are known as nativists.  Their basic assumption is that the characteristics of the human species as a whole are a product of evolution and that individual differences are due to each person’s unique genetic code. In general, the earlier a particular ability appears, the more likely it is to be under the influence of genetic factors. Estimates of genetic influence are called heritability. Examples of extreme nature positions in psychology include Chomsky (1965), who proposed language is gained through the use of an innate language acquisition device. Another example of nature is Freud’s theory of aggression as being an innate drive (called Thanatos).

Characteristics and differences that are not observable at birth, but which emerge later in life, are regarded as the product of maturation. That is to say, we all have an inner “biological clock” which switches on (or off) types of behaviour in a pre-programmed way.

The classic example of the way this affects our physical development is the bodily changes that occur in early adolescence at puberty.

However, nativists also argue that maturation governs the emergence of attachment in infancy, language acquisition, and even cognitive development.

EVIDENCE FOR THE NATURE DEBATE

BEHAVIOURAL GENETICS

Scientific research methods and lots of evidence from many different fields.

NON-EXPERIMENTAL RESEARCH METHODS OF THE GENETIC APPROACH

METHODS THAT ANALYSE THE FREQUENCY SCHIZOPHRENIA OCCURS IN FAMILIES.

  • CONCORDANCE RATES:

    The percentage likelihood that if one individual in a pair has a trait the other individual also has that trait.

  • A PEDIGREE

    A pedigree is a genetic representation of a family tree that diagrams the inheritance of a trait or disease through several generations.

  •  FAMILY STUDIES

    Investigate how much a characteristic run in a family e.g., the concordance/correlations of rates in 1st, 2nd, and 3rd-degree relatives (correlations essentially).

  • TWIN STUDIES CONCORDANCE RATE OF TWINS -CORRELATIONS ESSENTIALLY

    Look at a particular characteristic in MZ twins raised together and compare it with DZ twins. If the characteristic has a higher concordance rate in MZ twins it indicates a genetic basis This gives an indication as to how much the characteristic is due to genetics. A characteristic that is 100% due to genetics (e.g., blood type) would have a 100% concordance rate in MZ twins.

    A very straightforward way to estimate the influence of genes is to compare DZ twins who are raised together with MZ twins who are raised together. The only thing that differs between the two types of twins is their DNA so, when MZ twins end up more like one another than DZ genes are inferred If a trait was 100 percent heritable, then MZ twins would be exactly the same as one another. If a trait was zero percent heritable, then DZ would be no more like one another than MZ twins.

    In practice, we do not see either of these two extremes occurring. What is commonly referred to by behaviour geneticists as the "Heritability of Everything" paper (a meta-analysis, or systematic combination of available data, of twin studies across all outcomes) showed that the average correlation between identical twins was 0.6, and the average correlation between fraternal twins was 0.3. So, in neither group are the twins exactly alike (that would be a correlation of 1.0), nor are they entirely dissimilar (a correlation of 0.0). And, consistently across outcomes, identical twins are on average more like one another than are non-identical twins.  All this together means that, across everything we have studied, heritability is not 100 percent, but it is not zero percent either.

  • CONCORDANCE RATES OF SEPARATED MZ TWINS

    The reason MZ twins might have high concordance rates is because of their identical appearances as a result they might be treated as if they’re one person by many people Separated MZ twin studies (and there are not many as you can imagine) are conducted to separate environment and biology, e.g., nature and nurture that was not clear from studies that looked at the concordance rates MZ twins living together.

  •  CHILDREN OF DISCONCORDANT MZ TWINS.

    Even separated MZ twins’ studies can’t rule out nurture. But looking at the offspring of the MZ twins who didn’t develop schizophrenia, but their MZ twin did (in other words, looking at MZ twins’ pairs who were dis-concordant for schizophrenia) might rule out nurture. Very hard to conduct such studies because of the difficulties of obtaining such a niche sample.

  •  OTHER METHODS: ADOPTION STUDIES

    Compare a trait or characteristic of an adopted child with their biological relative and adopted parents. This controls for environmental influences, separate environment, and biology, e.g., nature and nurture that was not clear from family studies. If a trait or characteristic is heritable, then children should show greater similarity to their biological parents than adopted parents. If concordance/ correlation/similarity for adopted children is higher with natural parents than adopted parents, then the trait is biological.

EXPERIMENTAL RESEARCH METHODS OF THE GENETIC APPROACH

Physiological techniques. Physiological techniques are directed at exploring the functional properties of organisms.

Scans: fMRI, PET, Spectre, MEG, CT, plus

 GENE SEQUENCING

Use DNA analysis to investigate whether certain genes are associated with certain traits

  • Researchers use family histories. They compare DNA sequences of family members to identify genes involved in mental illness. First, they divide the family into two groups: affected and unaffected. Next, the researchers look for segments of chromosomes that are more common in affected people compared to unaffected. They narrow the segments down to specific genes to study further. Because people have complex and varied lives, in-depth studies are often done using animals in a controlled lab setting too.

  • In recent years, genome-wide association studies (GWAS) have emerged as a major approach in behavioural genetics. A GWAS uses genetic testing to identify numerous genetic differences across many individuals, then analyse the association between these differences and personality traits or other outcomes.

  •  Studies of twins who either do or do not have identical genomes allow for estimates of the degree to which genes drive the variation in psychological traits.

  • Experimental breeding. Genetically diverse lines of organisms can be crossed in such a way to produce different behaviours.

  • Cytogenetic techniques. Cytogenetics focuses on the microscopic examination of genetic components of the cell.

  • ·Biochemical techniques. Biochemistry is carried out at the cellular or sub-cellular level, generally on cell extracts.

Researchers in the field of behavioral genetics study variation in behavior as it is affected by genes, which are the units of heredity passed down from parents to offspring.

Family studies (concordance rates of 1st, 2nd, and 3rd-degree relatives and adoption studies. Behavioral genetics has enabled psychology to quantify the relative contribution of nature and nurture with regard to specific psychological traits. One way to do this is to study relatives who share the same genes (nature) but a different environment (nurture). Adoption acts as a natural experiment that allows researchers to do this.

Empirical studies have consistently shown that adoptive children show greater resemblance to their biological parents, rather than their adoptive, or environmental parents (Plomin & DeFries, 1983; 1985).

MZ and DZ twins, separated twins, and adoption studies. Another way of studying heredity is by comparing the behaviour of twins, who can either be identical (sharing the same genes) or non-identical (sharing 50% of genes). Like adoption studies, twin studies support the first rule of behavior genetics; that psychological traits are extremely heritable, about 50% on average.

The Twins in Early Development Study (TEDS) revealed correlations between twins on a range of behavioral traits, such as personality (empathy and hyperactivity), and components of reading such as phonetics (Haworth, Davis, Plomin, 2013; Oliver & Plomin, 2007; Trouton, Spinath, & Plomin, 2002).

“We now know that DNA differences are the major systematic source of psychological differences between us. Environmental effects are important but what we have learned in recent years is that they are mostly random – unsystematic and unstable – which means that we cannot do much about them.” Plomin (2018, xii)

THE NATURE DEBATE

Empiricism (Extreme Nurture Position)

At the other end of the spectrum are the environmentalists – also known as empiricists (not to be confused with the other empirical/scientific approach).

Their basic assumption is that at birth, the human mind is a tabula rasa (a blank slate) and that this is gradually “filled” as a result of experience (e.g., behaviorism).

From this point of view, psychological characteristics and behavioral differences that emerge through infancy and childhood are the results of learning.  It is how you are brought up (nurture) that governs the psychologically significant aspects of child development and the concept of maturation applies only to the biological.

For example, Bandura’s (1977) social learning theory states that aggression is learned from the environment through observation and imitation. This is seen in his famous Bobo doll experiment (Bandura, 1961).

How can you tell if a trait is inherited or environmental? It’s tricky, isn’t it? Environmental characteristics can be misleading, especially if they’re shared across multiple family members.

One way to describe the difference between inherited and environmental traits is nature vs. nurture.

A useful example is ‘pierced ears’, because you can see it in someone’s physical appearance. You might have had your ears pierced to wear earrings like your mother and grandmother before you, but when you were a baby, your ears weren’t naturally pierced.

Even though this trait is shared over different generations, it isn’t inherited. Piercing your ears happened after you were born due to contact with the environment.

If you grew up in a place where piercing ears was not a common thing to do, you might not have them pierced.

Consider the example of ‘knowing how to ride a bike’. What if you grew up in a place where there were no bikes? This trait is influenced by your environment rather than inherited, so you would not be able to instinctively know how to ride a bike – not without practice, at least.

What are thought to be environmental characteristics?

Unlike inherited characteristics, environmental characteristics are ones that are not passed down from parent to child. These can include:

Education and social class.

  • Beliefs and religion.

  • Favourite genres of music, Favourite colour, etc, Fashion sense, e.g., Pierced ears, tattoos

  • Number of languages spoken and your accent

  • Hobbies, e.g., the ability to ride a bike, access to clubs, and sports. Preference for dogs or cats (or any other pet!)

  • Wellness and health. Nurture suggests that poor eating habits and the environment can provide a pathway to obesity, and the inability to control personal behaviours that contribute to high blood pressure

  • The environment influences the way we act and our personalities. 'nurture' can refer to parents and teachers - essentially who you grew up with.

  • Gender roles

    Research areas

  • Behaviorism: Classical Conditioning: Little Albert Experiment, Pavlov

  • Operant Conditioning: Skinner’s box

  • Social Learning Theory (Bobo Doll experiment)

  • Social Influence experiments, Milgram, Asche, and Zimbardo

  • Bronfenbrenner’s Ecological Systems Theory

  • Social Roles: Mother, Father, wife, husband, sister, brother, friend.

  • Attachment Styles: plus other childhood experiences. Relationships (social), and culture are all from the outside world, Privation (e.g., The studies by Rutter)

  • Trauma: abuse, both physical and emotional may lead to the development of a mental illness and emotional disturbance: such as being bullied - loneliness, lack of emotional support, or traumatic experiences.

  • Did you know there are a few plants that change colour based on the type of soil they’re planted in? This would mean that in these cases, flower colour isn’t an inherited trait, but closer to an environmental one!

EVIDENCE FOR THE NATURE DEBATE

Behaviourists use empirical research methods. Observation, skinner’s box.

Social learning theory (SLT) is harder to prove experimentally because of ethics and a wealth of extraneous variables.

Proving other environmental influences is also difficult for the same reasons as SLT.

QUESTIONS

WHAT PSYCHOLOGY APPROACHES ARE NATURE AND WHAT APPROACHES ARE NURTURE? (7 MARKS)

PSYCHODYNAMIC, BEHAVIOURAL, SOCIAL LEARNING THEORY, HUMANISM, COGNITIVE, EVOLUTIONARY, NEUROSCIENCE.

Which of the following terms best represents the view that biology and environment work together to determine behaviour? Shade one box only. (Total 1 mark)

  • A: Determinism

  • B: Ethnocentrism

  • C: Holism

  • D: Interactionism

  • E: Reductionism

What is meant by the ‘nature-nurture debate’ in psychology? (Total 2 marks).

Read the item and then answer the questions that follow. Researchers used a test to measure the mathematical reasoning ability of pairs of identical and non-identical twins. If both members of a pair scored similarly on the test, they were said to be ‘concordant’. This type of study is known as a concordance study. The outcome of the research with the concordance rates expressed as a percentage 

THE CONCORDANCE RATE FOR MATHEMATICAL REASONING ABILITY

GENETIC RELATIONSHIP CONCORDANCE RATES

Identical twins
(100% shared genes) 58%

Non-identical twins
(50% shared genes) 14%

Briefly explain the outcome of the study in relation to the nature-nurture debate. (Total 2 marks)

Nature deals with anything that is determined by genes and hereditary factors. What are some examples of characteristics that are influenced by nature? (Total 4 marks)

Nurture deals with anything that is heavily influenced by the environment. What are some characteristics that are influenced by nurture? (Total 4 marks)

A03: EVALUATION

Discussion points:

  • Use of evidence to support the influence of nature eg twin studies showing higher concordance for MZ pairs than DZ pairs

  • Use of evidence to support the influence of nurture eg studies of social learning

  • Need to take an interactionist approach rather than a dichotomous view

  • Links with approaches in psychology eg how the biological approach supports the nature side of the debate.  

  • Use of examples from topics to support arguments

  • Credit other relevant material.

The Nature of Nurture

Nurture assumes that correlations between environmental factors and psychological outcomes are caused environmentally. For example, how much parents read with their children and how well children learn to read appear to be related. Other examples include environmental stress and its effect on depression.

However, behavioral genetics argues that what looks like environmental effects are to a large extent really a reflection of genetic differences (Plomin & Bergeman, 1991).

People select, modify and create environments correlated with their genetic disposition. This means that what sometimes appears to be an environmental influence (nurture) is a genetic influence (nature).

So, children that are genetically predisposed to be competent readers will be happy to listen to their parents read them stories, and be more likely to encourage this interaction.

Asking which is more important, genes or environments, is kind of like asking which is more important in making an ordinary automobile run, spark plugs or gasoline. You need both. They’re both absolutely essential. Asking the question “which one is more important?” really doesn’t make any sense.

GENOTYPE:

  • A person’s genetic make-up, as represented by the genes on the 23 pairs of human chromosomes.

  • A genotype never changes; phenotype can change over time.

    PHENOTYPE: A person’s actual/observable characteristics are determined by genetics and the environment. e.g., physical appearance, behavioural characteristics, and personality.

An example to illustrate the difference between genotype and phenotype

In relation to intelligence, they may explain that an individual might have an intellectual potential (genotype) but they require environmental stimulus such as education for this to develop.

PKU is an example of a disorder caused by a defective gene resulting in severe learning difficulties. However, if identified early, and treated with a special diet, individuals show normal levels of intelligence. Other examples e.g., schizophrenia

THE INTERACTIONIST APPROACH

However, in recent years there has been a growing realisation that the question of “how much” behaviour is due to heredity and “how much” to the environment may itself be the wrong question.

The “how much” question assumes that psychological traits can all be expressed numerically and that the issue can be resolved in a quantitative manner.

Heritability statistics revealed by behavioral genetic studies have been criticized as meaningless, mainly because biologists have established that genes cannot influence development independently of environmental factors; genetic and nongenetic factors always cooperate to build traits. The reality is that nature and culture interact in a host of qualitatively different ways (Gottlieb, 2007; Johnston & Edwards, 2002).

Which is an example of polygenic inheritance?

What are polygenic inheritance examples? Human phenotypes or human physical traits such as hair color, height, skin color, blood pressure, intelligence, autism, and longevity are some of the examples of polygenic inheritance.

Instead of defending extreme nativist or nurturist views, most psychological researchers are now interested in investigating how nature and nurture interact.

For example, in psychopathology, this means that both a genetic predisposition and an appropriate environmental trigger are required for a mental disorder to develop. For example, epigenetics state that environmental influences affect the expression of genes.

Interactionist Approach: Definition

The interactionist approach combines explanations to explain a behaviour or phenomenon, incorporating biological, psychological, and social perspectives, the view that both nature and nurture work together to shape human behaviour. It combines all aspects of nature and nurture debates to determine potential causes of behaviours and, ultimately, the best way to treat mental health issues. Schizophrenia is a good example. Interactionist Approach Example: The Diathesis-Stress Model

The diathesis-stress model is an example of the interactionist approach. It explores how predispositions (vulnerabilities) to disorders can be triggered by environmental stressors, resulting in disorders such as depression and schizophrenia.

The diathesis-stress model, first introduced by Meehl (1962) in schizophrenia, is a psychological concept that holds that schizophrenia is due to a diathesis (an internal vulnerability) and an environmental trigger (stressor). This internal vulnerability or diathesis is predisposed, and Meehl initially held that this was due to a single ‘schizogene’.

If a person did not have this gene or genetic susceptibility, Meehl argued, no external stressors could cause schizophrenia. However, if they did have the gene, childhood trauma (such as experiencing expressed emotions or family dysfunction) or a negative life event could trigger schizophrenia.

EXPERIENCE DEPENDANT PLASTICITY ALSO KNOWN AS DEVELOPMENTAL PLASTICITY is also an example of the interactionist approach

The brain is not fully matured at birth and this may be because humans needed their brain to develop in a culturally specific way in order to navigate their environment successfully. During the early years, the brain creates many connections and pathways. The recurrence of an action or experience helps to carve these pathways into the brain. Once they have become strengthened adequately, they become permanent.

CRITICAL PERIODS

Experience expectant plasticity is tied to the concept of a critical period.

Experience-expectant plasticity is when the brain expects to have certain experiences, eg., seeing a face before it can wire up correctly. Experience-expectant plasticity refers to the integration of specific environmental stimuli into the normal patterns of development. Certain environmental exposures are needed during limited critical, or sensitive, periods in a baby’s development and are essential for healthy maturation. For example, finches need to hear adult songs before sexual maturation in order for them to learn to sing at a species-appropriate level of intricacy. Humans need to experience hearing language or seeing faces during critical stages of their cortex’s development. If they do not receive the correct stimuli then this area may be pruned away after the first six months of life.

In short, experience-expectant plasticity is the generalised development of neuron connections that occur as a result of common experiences that all humans are exposed to in a normal environment. It is thought that the human brain evolved to start life with an innate desire to wire up specific sensory experiences: For example, faces to enable face recognition, visual-spatial information for navigation; specific voices for language acquisition,

What Is Epigenetics?

Epigenetics is the term used to describe inheritance by mechanisms other than through the DNA sequence of genes. For example, features of a person’s physical and social environment can affect which genes are switched on, or “expressed”, rather than the DNA sequence of the genes themselves.

Stressors and memories can be passed through small RNA molecules to multiple generations of offspring in ways that meaningfully affect their behavior

One such example is what is known as the Dutch Hunger Winter, during last year of the Second World War. What they found was that children who were in the womb during the famine experienced a life-long increase in their chances of developing various health problems compared to children conceived after the famine.

Epigenetic effects can sometimes be passed from one generation to the next, although the effects only seem to last for a few generations. There is some evidence that the effects of Dutch Hunger Winter affected grandchildren of women who were pregnant during the famine.

Therefore, it makes more sense to say that the difference between two people’s behavior is mostly due to hereditary factors or mostly due to environmental factors.

This realization is especially important given the recent advances in genetics, such as polygenic testing.  The Human Genome Project, for example, has stimulated enormous interest in tracing types of behavior to particular strands of DNA located on specific chromosomes.

If these advances are not to be abused, then there will need to be a more general understanding of the fact that biology interacts with both the cultural context and the personal choices that people make about how they want to live their lives.

There is no neat and simple way of unraveling these qualitatively different and reciprocal influences on human behavior.

Epigenetics: The Agouti Mouse Study

Waterland and Jirtle’s (2003) Agouti Mouse Study examines the relationship between nature and nurture, showing how epigenetic mechanisms change gene expression in lab mice and, by extension, human beings.

The video below provides context for the Agouti Mouse Study, and outlines the development of an epigenetic approach to our understanding of disease.

Evidence for an Interactionist Approach

  • Genes, Interactions, and the Development of Behaviour

  • Diathesis stress model: Schizophrenia: MZ concordance is 46%

  • Epigenetics: Agouti Mouse Study

  • MAOA L PSYCHOPATH GENE

MORE ON EPIGENETICS

New research into epigenetics—the science of how the environment influences genetic expression—is changing the conversation. What counts is not what genes you have so much as what your genes are doing. And what your genes are doing is influenced by the ever-changing environment they’re in. Factors like stress, nutrition, and exposure to toxins all play a role in how genes are expressed—essentially which genes are turned on or off. Unlike the static conception of nature or nurture, epigenetic research demonstrates how genes and environments continuously interact to produce characteristics throughout a lifetime.

How does the science of epigenetics change the seemingly age-old nature versus nurture debate? For the longest time, the nature-nurture debate has been cast as a kind of contest between genes and experiences. The thought was that we might have some characteristics that are caused primarily by genetic factors and other characteristics that are caused primarily by experiential factors. What epigenetics are making clear is that’s a faulty way to think about the situation, because it’s not true that genes do things independently of their contexts. Instead, genes do what they do because of the contexts that they’re in. Nature and nurture are always working together to produce all of our traits.

A study that illustrates the science of epigenetics?  The Developing Genome: An Introduction to Behavioral Epigenetics: The one that has drawn the most attention has been the one done by a team of researchers led by Michael Meaney and Moshe Szyf at McGill University. These researchers watched how rat mothers interacted with their babies. They discovered that some mothers naturally lick and groom their baby rats more than other mothers do. They also noticed that the mothers that licked and groomed their rats the most wound up with offspring that grew up to be adults that were less stressed out when they were put into mildly stressful situations. The mothers that licked and groomed their baby rats less, wound up with offspring that were more stressed out. In order to determine if this was an effect of experience, the researchers cross-fostered the baby rats, so the ones born to the high-licking and grooming mothers were raised by the low-licking and grooming mothers. What they found was that it was the perinatal experience that made all the difference. It didn’t matter who you were born to—if you were raised by a low-licking and grooming mother, you would grow up to be a more stressed-out adult rat.

How can it be that these kinds of early experiences can have these long-term effects later on in adulthood? Meaney and Szyf traced the effect to epigenetics. Specifically, they discovered that in certain brain cells of baby rats, there are certain genes that get turned on when the babies are licked and groomed. Then, the turning on of those genes leads cells to build proteins that help moderate stress responses into adulthood, because the genes stay turned on. Meaney and Szyf’s work shows how it is that an experience can influence what an animal’s genes are doing, in a way that can have a long-term effect.

How does epigenetic research relate to humans? We don’t know as much about this, because we really can’t do tightly controlled experiments with human beings for ethical reasons. As a result, we don’t have a particularly concrete understanding of how this all works in people.

There are really two ways in which we can get insight into what’s going on in people. One is by looking at experiments that have been done on our primate relatives, the monkeys. There are a variety of studies on monkeys that show effects like those discovered in rats, where experiences influence the epigenetic states of certain genes in certain cells in monkeys’ bodies. The second way we can get insight into epigenetic phenomena in people is by doing correlational studies. In this way, even though we’re not doing experiments, we can see if certain kinds of experiences early in life are correlated with later epigenetic states in actual people. So far, these kinds of studies have revealed that this is indeed the case.

It’s not true that genes do things independently of their contexts…genes do what they do because of the contexts that they’re in.

Scientists have also discovered epigenetic effects of experiences that are less related to psychology. For instance, when they looked at certain cells in the muscles, they’ve seen epigenetic effects of exercise. And when they’ve looked at other cells in the body, they’ve seen epigenetic effects of diet.

From an epigenetics perspective what is known about how an experience like poverty might impact an individual’s biological processes and their outcome? There is an increasing amount of data that suggests that growing up poor has long-term effects on people. Let’s say we’re studying a person who grew up in an impoverished environment, but as he got older, the person was successful and reached a higher socioeconomic status. If scientists compare such a person’s epigenome to the epigenome of someone born into a higher socioeconomic status, and who has managed to stay at this level, they’ll find that the person who was poor in childhood has a different epigenetic state than the person who was born into greater wealth, even if both people are now equally wealthy. So, poverty seems to have consequences that produce effects that can be detected in the body decades later.

"In the Nature-Nurture War, Nature Wins. Environmental influences are important, too, but they are largely unsystematic, unstable and idiosyncratic." (From In the Nature-Nurture War, Nature Wins)

  "Take the most essential element: a child needs to be raised in a family, almost any kind of family, to develop the ability to speak a language. Since every single person in twin studies checks that box (i.e., is raised in a family of some sort), this factor never varies and thus does not predict differences in the ability to speak a language. But does this mean that the variable "has a family" doesn't matter in determining whether or not a person develops the ability to speak a language? Of course not! That's like saying that water has no influence on a fish's development because all fish live in water. Just because a variable doesn't vary doesn't mean it has no causal impact on a particular outcome. The parenting factors that are statistically associated with differences between individuals should never be confused with the parenting factors that cause the development of a trait within an individual. Genes could "account for" 100% of the variability in a trait in a particular twin study, but this does not mean that environmental factors are therefore unimportant in the development of the trait; parents still matter and will always matter. It turns out that parenting matters, just in a way different than originally assumed. Genes matter to the extent that they support parenting because like any other behavior, parenting behaviors are influenced by the genes ”and parents matter to the extent that they support the expression of genes."

Key Takeaways

  • The nature versus nurture debate involves the extent to which particular aspects of behavior are a product of either inherited (i.e., genetic) or acquired (i.e., learned) influences.

  • Nature is what we think of as pre-wiring and is influenced by genetic inheritance and other biological factors.

  • Nurture is generally taken as the influence of external factors after conception, e.g., the product of exposure, life experiences, and learning on an individual.

  • Behavioural genetics has enabled psychology to quantify the relative contribution of nature and nurture concerning specific psychological traits.

  • Instead of defending extreme nativist or nurturist views, most psychological researchers are now interested in investigating how nature and nurture interact in a host of qualitatively different ways. For example, epigenetics is an emerging area of research that shows how environmental influences affect the expression of genes.

The Nature-Nurture Debate

POSSIBLE EXAM QUESTIONS

  1. Which of the following terms best represents the view that biology and environment work together to determine behaviour? Shade one box only. (Total 1 mark)

  • A: Determinism

  • B: Ethnocentrism

  • C: Holism

  • D: Interactionism

  • E: Reductionism

2. What is meant by the ‘nature-nurture debate’ in psychology? (Total 2 marks).

Read the item and then answer the questions that follow. Researchers used a test to measure the mathematical reasoning ability of pairs of identical and non-identical twins. If both members of a pair scored similarly on the test, they were said to be ‘concordant’. This type of study is known as a concordance study. The outcome of the research with the concordance rates expressed as a percentage 

THE CONCORDANCE RATE FOR MATHEMATICAL REASONING ABILITY

GENETIC RELATIONSHIP CONCORDANCE RATES

Identical twins
(100% shared genes) 58%

Non-identical twins
(50% shared genes) 14%

3. Briefly explain the outcome of the study in relation to the nature-nurture debate. (Total 2 marks)

4. Nature deals with anything that is determined by genes and hereditary factors. What are some examples of characteristics that are influenced by nature?

5. Nurture deals with anything that is heavily influenced by the environment. What are some characteristics that are influenced by nurture? (Total 4 marks)

6. You may be thinking that both nature and nurture seem to be well-defined. Since they are so well-defined, then why is there such a huge debate about nature versus nurture? Discuss the nature-nurture debate in psychology (Total 16 marks).

7. Discuss the nature-nurture debate in psychology. Refer to at least two topics you have studied in your answer. (Total 16 marks)

8. Nature and nurture interact; both are vital to understanding and explaining human behaviour.’Referring to this statement, discuss the nature-nurture debate in psychology. (Total 16 marks)

ESSAY WRITING


Aspects to Cover in a Nature vs Nurture Essay

  • At first glance, a nature vs nurture essay seems to be easy. However, a limited view of the subject matter may cost you marks, which is why it is crucial to offer a well-rounded account of the debate. Here are some of the aspects that you might want to include in your essay on nature vs nurtureThe importance of the topic. The debate on what influences one’s personality, intelligence, and character is among the most prominent ones in psychology and other social sciences. Your task is to reflect on this and to attempt to justify why the debate is so important. What could be done if it were resolved one day? How does the dispute affect other subject fields and topics in psychology? How would the resolution help the study of psychology and human behavior to move forward? Would it help to prove certain theories or refute others, and what would be the effect on professional practice?

  • The origins of the debate. While you explore the first aspect, you might stumble upon the history of the nature vs nurture debate. Covering this theme in your essay could also earn you some extra marks. Merely summarizing historical facts is not enough, though, because your tutor is probably aware of them already. Instead, you should focus on why the debate started. Were there any developments in psychology that prompted it?

  • Prominent views. It is hard to omit the opinions expressed by famous scholars while writing an essay on this subject. John Locke, John B. Watson, Calvin Hall, and other authors had all shared ideas on the issue. If you need more names, try searching sample essays on nature and nurture online since most of them point out the key names. This might also help you to identify possible nature vs nurture essay titles.

  • Results of research studies. Research evidence is among the key nature vs nurture essay topics because there were many attempts to prove one or the other view. Examples of such studies may be cited in your textbook, so it should be the first point of your research. Your school’s library and Google Scholar might also give you more information. If you find any sources online, make sure that they are of academic quality, or you might lose marks your personal experience and thoughts. Because the controversy is so prominent, nearly all people who study psychology or social studies have an opinion on it. If the instructions don’t prevent you from doing this, you should share your thoughts on the debate between nature and nurture. Support your opinion with credible research evidence and link it to the work of other scholars. If you believe that the environment is more important than genes, why is that? What other theorists supported this view, and why did they? Your opinion, supported by relevant facts and views, may become an excellent nature vs nurture essay thesis.

Suggestions for further research. Try to think about what could be done to resolve the debate once and for all. What are the main gaps in studies on nature vs nurture and how could they be addressed by scholars?

Best Nature vs Nurture Essay Topics & Essay Examples

  1. Nature versus Nurture and Learning among Children

    Of much concern among modern researchers is the determination of the degree of influence of nature and nurture on the development of a child and the provision of learning experiences.

  2. As Nature Made Him: Summary and Analysis

    As aforementioned, the author of this book provides useful analysis of this aspect of personality. One of the greatest questions that readers get answer from this book is the question of nature vs.nurture in sexuality […]

  3. Alcoholism-Nature vs Nurture Debate

    The analysis on physiological physiology regarding alcohol shows that, alcohol displays feelings of superiority and fearless behavior and also, it reduces an individual’s fear.

  4. Nature Vs Nurture

    In most cases, nature determines the physical characteristics which in effect influence the behavior of an individual. These are traits which largely determined by the socio-cultural environmental factors or the way the individuals are socialized […]

  5. Human Development: Nature or Nurture?

    With studies and theories carried out to examine the impact of nature on the personal development and personality traits, heredity is an important factor in the development.

  6. Nature vs. Nurture: New Science Stirs Debate How Behavior Is Shaped

    A prime example of this nature of debates is the debate on whether nature or nurture has a greater bearing on the development of the diverse individual behavioral differences that exist.

  7. Physical and Mental Wellbeing: Nature versus Nurture

    In conclusion, the debates on nature versus nurture reveal that both innate health conditions and external factors shape the outcomes for physical and mental wellbeing of an individual.

  8. “Nature” Versus “Nurture”: Effects on Child Development

    Consequently, a child’s behavior cannot be viewed as solely attributable to the genetic composition of the parents and the hereditary characteristics.

  9. Violent Behavior: Nature vs Nurture

    Considering this circumstance, the shifts in one’s attitudes are likely to be ascribed to the modifications in conditions, which can be reported by families with children.

Most Interesting Nurture vs Nature Topics to Write About

  1. The Relationship Between Nature And Nurture On The Intelligence

  2. The Controversies Surrounding the Topic of Nature Versus Nurture

  3. The Nurture Side Of The Dichotomy Nature Versus Nurture

  4. The Formula For Fruition: The Age Old Debate Of Nature Versus Nurture By Kendra Cherry

  5. The Meaning Of Nature And Nurture In Psychology

  6. The Role of Nature vs Nurture in Violent Behavior

  7. Influence Of Nature Versus Nurture On Child Development

  8. The Role Of Nature And Nurture : Adolescence Eating Disorders

  9. The Nature Vs. Nurture Debate In Learning More About Alcoholism

  10. The Psychological Argument Between Nature Vs Nurture

  11. The Role of Nature and Nurture in Human Development

  12. The Influence of Nature Versus Nurture on an Individual Human Behavior

  13. Use Of Nature And Nurture Based Studies On Epigenetics

  14. The Impact of Nature and Nurture on Huck’s and Finn’s Personality and Behavior in The Adventure of Huckleberry Finn by Mark Twain

  15. The Correlation between Nature and Nurture in the Personal Development

  16. Role of Nature and Nurture in Language Development

  17. Personality, Behavior, and the Significance of Nature v. Nurture

  18. The Disputes Concerning the Popular Nature vs. Nurture Argument

  19. Understanding the Role of Nature Versus Nurture in Alcohol Addiction

  20. Wild Child Vs Nature And Nurture

Good Nature vs Nurture Topics

  1. The Importance of Nature Verses Nurture in Shaping Behavior and Personality

  2. The Differences Between Boys and Girls from Combination Between Nature and Nurture

  3. The Role of Nature and Nurture in Human Homosexuality

  4. The Nature Versus Nurture Debate in The Blasphemy of Talking Politics During Bach Year, an Article by Susan McClary

  5. What Roles Do Nature And Nurture Play On Children ‘s

  6. What Differentiates The Entrepreneurs From Non-Entrepreneurs On Nature And Nurture

  7. The Source of Violence: Nature Vs. Nurture

  8. Gender And Socialization: Nature Or Nurture

  9. How Nature and Nurture Affects the Pies in Adolescence and Adulthood

  10. The Debate Between Criminal Nature and Criminal Nurture: William Sheldon Theory

  11. The Nurture and Care from Nature and the Damage Caused by Humans to Our Environment

  12. The Evolutionary Theory Of Nature Vs Nurture

  13. The Personality and Biology Differences in Nature Versus Nurture and Man Versus Woman Situations in Daily Life

  14. The Importance of Twin Studies in the Nature Versus Nurture Debate

  15. The Scientific And Cultural Debate Of Nature Vs Nurture

  16. The Issue of Nature Versus Nurture in the Development of Serial Killers

  17. The Role Of Nature Vs. Nurture, Culture And Gender, And Family

  18. What Makes A Monster Nature Vs Nurture In Mary Shelleys Frankenstein

  19. The Theme of Nature Versus Nurture in Shelly’s Frankenstein

  20. The Psychology Field Of Study About Nature And Nurture

Questions About Nature vs Nurture

  1. How Children Develop and the Interplay of Nature vs Nurture?

  2. How Nature vs Nurture Affect Human Development?

  3. Homosexuality: Nature vs Nurture?

  4. How Do Nature vs Nurture Work Together Example?

  5. How Does Nature vs Nurture Affect Human Behavior?

  6. Why Is Nature vs Nurture Called a False Debate?

  7. Nature vs Nurture: Do Our Genes Affect Our Personalities?

  8. Nature vs Nurture: Which Has a More Significant Influence on Child Development?

  9. How Do You Argue Nature vs Nurture?

  10. Nature vs Nurture: Who’s to Blame for Acts of Violence?

  11. How Does Nature vs Nurture Affect Intelligence?

  12. Nature vs Nurture: Which Is the Origin of Virtue?

  13. How Does Shelley Represent the Nature vs Nurture Debate?

  14. Nature vs Nurture: Which Determines Personality?

  15. What Are Examples of Nature vs Nurture?

  16. Nature vs Nurture: What Does Matter More?

  17. What Is Stronger Nurture vs Nature?

  18. Why Nurture Is Better than Nature?

  19. How Does the Nature vs Nurture Debate in May Affect the Physical?

  20. What Is Nature vs Nurture in Child Development?

  21. How Nature vs Nurture Influence Substance Abuse?

  22. Twin Studies: What Can They Tell Us About Nature vs Nurture?

  23. How Does Nature vs Nurture Affect the Development of Social-Emotion Attributes?

  24. Who Won Nature vs Nurture?

  25. How Nature vs Nurture Apply the Principles of Life?

  26. What Is the Difference Between Nature vs Nurture in Child Development?

  27. What Is the Main Idea of Nature vs Nurture?

  28. Is Nature vs Nurture Misleading?

  29. Nature vs Nurture: What Impacts a Child’s IQ?

  30. How Does Nature vs Nurture Affect Human Development?

MODEL ANSWER

Essay title:

Describe and evaluate the nature–nurture debate in psychology. (16 marks)
Amongst the most famous and consistently evoked debates
in psychology is that often summarised (and simplified) as

nature vs. nurture.

The nurture side of the debate suggests that our behaviour is the product of environmental influences which are caused by our interactions with the environment. These interactions include our social and physical world and can be referred to as ‘experience’. For example, it has been suggested that attachment behaviours might be explained as the result of classical and/or operant conditioning.

The term ‘nurture’ has been defined accurately.

While the example is correct, it could have been developed further to explain how classical/operant conditioning are an example of ‘nurture’.

The term ‘nature’ has been defined accurately and research evidence has been used effectively to enhance the definition.

Research evidence was used to evaluate the debate.

A highly effective evaluation point.

Nature refers to innate influences on human behaviour and cognition (biological or genetic), i.e. to any characteristics determined by genes, either at birth or subsequently. Many psychological disorders, for example schizophrenia, are said to have a genetic component. Research has found concordance rates of 40% in monozygotic twins and 7% in dizygotic twins, suggesting that nature is a powerful contributing factor in schizophrenia. Similarly, Huntingdon’s disease is a genetically transmitted disorder that usually emerges between the ages of 30 and 50, although it can appear at any time since the genetic cause is innately present.

As psychological knowledge has deepened, the nature-nurture debate has grown increasingly complex, to the point where some psychologists believe that it is now a meaningless distinction and a pointless distraction from more important matters. Plomin et al. (1977) have suggested the idea of “passive influence” in which genetic influences on parental behaviour create a particular environment in which their children are raised. For example, parents with a genetically influenced mental illness (like schizophrenia) may create an unsettled home environment. This suggests that disorders like schizophrenia may be the result of indirect influences. Furthermore, these ideas also demonstrate the possible interaction between nature and nurture and demonstrate that nature can actually affect nurture.

Other psychologists have suggested that the influence can operate in the other direction. Research examining neural

Plasticity suggests that life experiences (nurture) shape our biology (nature). For example, Maguire et al. (2000) investigated the hippocampi volume of London taxi drivers. She found that this region of the brain was larger in taxi drivers in comparison to non-taxi drivers. Consequently, Maguire concluded that driving a taxi (nurture) actually had an effect on the size of the hippocampi (nature).

An excellent evaluation point drawing on biopsychology research evidence.

The concluding sentence could have been developed further to say why this is a problem for the debate.

An example of the interactionist approach is used effectively.

Most psychologists now believe that we should consider both nature and nurture and therefore adopt an interactionist approach. A celebrated example of the interactionist approach is the diathesis-stress model which suggests that even though one may be born with a biological vulnerability, for example, a gene for depression, the depression will only develop if it is triggered by a stressor in the environment. Research has demonstrated that not everyone with the gene for depression goes on to develop it, suggesting instead that one’s nature is only expressed under certain conditions of nurture.

The interactionist approach has led to the development of theories/models that have helped improve our understanding and treatment of many physical and psychological illnesses.


MARK SCHEMES FOR 16 MARKER QUESTIONS

A01 CONTENT

  • The debate about the relative importance of heredity and environment in determining behaviour.

  • The nature side of the debate assumes heredity is more important

  • The nurture side of the debate assumes environment and experience are more important

  • Nature aspect is rooted in the nativist theory that knowledge/abilities are innate

  • Nurture is rooted in the empiricist theory that knowledge derives from learning – Locke’s view of the mind as a ‘tabula rasa’ or blank slate on which experiences are written

  • Possible discussion points:

  • Use of evidence to support the influence of nature eg twin studies showing higher concordance for MZ pairs than DZ pairs

  • Use of evidence to support the influence of nurture eg studies of social learning

  • Need to take an interactionist approach rather than a dichotomous view

  • Links with approaches in psychology eg how the biological approach supports the nature side of the debate.  

  • Use of examples from topics to support arguments

  • Credit other relevant material.

EXAMINER’S COMMENTS FOR 16 MARKER QUESTIONS

  1. Students generally demonstrated sound knowledge and understanding of the nature-nurture debate and were able to use relevant terminology correctly. It was also evident that students were knowledgeable about the standing of different approaches in psychology in relation to the debate. Disappointingly, some students seemed to be writing a ‘pre-prepared’ essay on the nature-nurture debate which did not quite fit the question, again illustrating the requirement to read the question carefully and plan an answer to the specific question set. The answer required reference to the statement which concerned the interaction between nature and nurture. Many answers did refer to interactionism, often using appropriate examples such as Phenylketonuria (PKU), schizophrenia, and/or language development. However, some students offered little or no discussion of the interaction of nature and nurture and this restricted the marks that could be awarded. The skill of using topics/approaches/research to illustrate points raised in the essay on the nature-nurture debate seems to be improving. However, some answers still begin to read like a PSYB3 answer where, for example, there might be a whole page on theories of crime, with a detailed outline of research followed by an evaluation of the research, with the focus of the debate lost. The best answers made clear but succinct references to topic areas/research in order to illustrate the debate.

  2. Given that a nature-nurture question has not appeared as an extended writing question before, students might have been expected to have been better prepared. In fact, answers to this question were generally very disappointing with marks often limited to Level 2 because of basic misunderstanding. The main problem seems to have been a complete lack of understanding of the concept of ‘a debate’. This was evident right at the start of the vast majority of answers where paragraphs would typically begin with ‘The nature debate argues that…’ or, ‘According to the nurture debate…’. Similar problems arose where attempts at discussion included phrases such as, ‘One strength of the nature debate is…’ or ‘One criticism of the nurture debate is…’ Inevitably it was quite hard to award much credit for such answers because the sentences did not make a great deal of sense. Further problems arose for students who offered an ‘approaches’ answer, describing and evaluating the biological and learning approaches in turn, with hardly any reference to nature or nurture. Not surprisingly, the focus on treatments was not usually successful, since the debate is really about the origins of behaviour. A relatively small number of competent students recognised the complexities of the debate and referred to constructivism, niche picking, and the reciprocal effects of nature and nurture.

    FURTHER READING

https://www.theguardian.com/science/2018/sep/29/so-is-it-nature-not-nurture-after-all-genetics-robert-plomin-polygenic-testing