Psychology and science, social control, cultural issues and the nature-nurture debate

Transcription

1 D 4.6 Debates Psychology and science, social control, cultural issues and the nature-nurture debate This section of the course requires that you know four debates. They are discussed here in detail. Although there is not a huge amount of content to each debate, what the examiners are testing for is your ability to link ideas from the AS approaches and A2 applications to the debates. This guide will take you through how various approaches and applications tie into each debate. Psychology as a science What is meant by science? When we look at different approaches and applications to psychology, we can evaluate both their content (concepts, theories and models) and methodologies (research methods and key studies) in terms of how scientific they are. Elements of study that make something scientific are: objectivity there must be no individual subjectivity (due to interpretation) affecting study reductionism studying complex areas using one sole focal aspect operationalisation making variables being investigated quantifiable and measurable other elements include: reliability, credibility, control, empirical data and hypothesis testing AS approaches and science Social approach and science field experiments such as Hofling et al. (1966) and laboratory experiments such as Tajfel (1970,71) use controlled methods of study which offer reductionism and operationalisation of variables the social approach aims for controlled and objective studies however, methodologies using interviews or questionnaires may introduce subjectivity as they require interpretation ethnographic studies looking for differences across cultures, such as Meeus and Raaijmakers (1986) tend to generate qualitative data which are not likely to be scientific Cognitive approach and science field experiments such as Godden and Baddeley (1975) and laboratory experiments such as Craik and Tulving (1975) use controlled methods of study which offer reductionism and operationalisation of variables other research methods include brain scanning and neuroscience studies, which are scientific the approach studies processing in the brain, which has access to measurable biological information cognitive psychology looks at concepts which are hard to measure (such as levels of processing, cue-dependency) case studies are used (such as Clive Wearing) which are hard to generalise to form a scientific body of knowledge Psychodynamic approach and science there was no original scientific experimentation by Freud, but later studies have used such methodologies, such as Adams et al. (1996) who looked into homophobia case studies were used a lot by Freud to base the psychodynamic concepts on, which are not generalisable or scientific, as they require subjective interpretation and biased samples, and collect ambiguous qualitative data concepts are not scientifically or objectively measurable Biological approach and science laboratory experiments which use scientific techniques, such as brain scanning such as De Bellis et al. (2001) careful controls as you are testing a hypothesis studies are seen generally as measurable, credible and reliable, and the content is regarded as scientific although content is scientific, case studies such as Money (1975) are not

2 Learning approach and science laboratory experiments often involving animal studies are used, such as Skinner (1935), Seligman (1967) and Pavlov (1927) there is reductionism as behaviour is reduced to parts to make it more measurable (such as Seligman using his dogs to test his learned helplessness theory) the approach aims to discover the general laws of behaviour and development, which is scientific however, it is hard to generalise from animal studies as the findings may not apply to humans making them less scientific further, ignoring cognition and emotions ignores human functioning Hypothetico-deductive model Karl Popper was concerned about showing whether a psychological theory was scientific, and whether it was true. He proposed that the development of a scientific theory is as follows: Amending or agreeing the theory Theory Empirical testing against reality Deriving a hypothesis - science involves proposing explanations (hypotheses) based on a scientific theory - this is tested against experience, by observation and experimentation (empirical testing as based on experiences with the world data are gathered by the senses) - scientific knowledge is built up based on a means of testing and amending the hypothesis, and the cycle repeats - this is the hypothetico-deductive model of reasoning - if not proven, a theory may be rejected rather than amended This model can be applied to psychology, as this cycle of developing theories and testing them to accept, reject or amend the theories, is what psychology is all about. This can be noticed in observations and experiments. If it s a psychological hypothesis you are testing by experimentation, you are trying to build knowledge in a scientific way you cannot do with a case study. Falsification Popper acknowledged that psychological hypotheses, as with any in the sciences, make specific predictions based on theories from an area of study, and that any hypothesis being tested runs the risk of being proven wrong. It must be possible to show that they are wrong, and this is called falsification. Popper therefore believed that the difference between sciences and non-sciences was not the ability to verify, but the ability to falsify. Scientists will take a hypothesis which they wish to test, and use experimentation to try and disprove the theories, and by this means try to reject the hypotheses in question. Therefore, studies which do not disprove the theories mean that those theories must be tentatively accepted even if we cannot prove they will not be falsified in the future. This is where psychology could be argued to be less scientific: scientists try to disprove their theories in order for accepting of hypotheses to be more valid, whereas psychologists always true to prove hypotheses. Psychology is said never to try and falsify theories, as a psychologist is unlikely to try and disprove their own theory. The paradigm Philosopher of science, Thomas Kuhn, suggested that science cycles, with new sets of beliefs about science replacing older sets of beliefs. The sets of beliefs, known as the paradigm, are the underpinning of assumptions of a scientific approach. The paradigm is used to explain and predict the world, but also defines the way in which research is conducted. When a set of theories are improved through new evidence, and methods change, there is a paradigm shift. When we consider applying the paradigm approach to science, it is difficult to apply to psychology. This is because it is hard to suggest that psychology has just one paradigm it is not just one area of knowledge, and there is never only one way of looking at an issue with psychology. So from Kuhn s perspective, it cannot be said that psychology is a science: different approaches to psychology explain things very differently.

3 Reductionism Science uses reductionism it is hard to operationalise variables that are too broad, so a specific part of the whole complex nature may be studied in particular. Holism involves looking at the whole situation, as this is sometimes more relevant than just studying each individuals component (holists take the view that the whole adds up to more than each part added together). In psychology, a reductionist view is used almost exclusively in experimentation, isolating behaviours to be tested the variables. The independent variable and dependent variables need to be able to be separated and measured in order to test the hypothesis, and psychology generally achieves this. The only exception is in case studies. Most case studies use holism, as they gather qualitative and in-depth data which cover more than one aspect of behaviour. This means they cannot be transferred to correlations, etc. Holistic studies are not scientific, but since the vast majority of psychological study and experimentation uses reductionism, it can be argued from this sense that psychology is a science. Scientific subject matter Psychology covers a number of areas which are seen to be scientific. The sciences are areas of study where scientific methods are used. Generally there is a tendency to call specific subjects scientific because they involve elements of biology, chemistry or physics, but by this definition of a science, there are other areas which are also sciences, such as environmental sciences and geological sciences. The areas which are seen as scientific by the standard definition of science include studying genes, hormones and drug therapies. However, by this approach to science we need to take into account that it also covers areas within different approaches which are far less scientific, because the concepts are not easily measurable. Most of the psychodynamic approach suffers this weakness, as Freud was subjective and used no scientific methods at all; the same goes for psychoanalysis as a therapy. Psychologists appreciate this and when evaluating work will criticise studies on being unscientific. Psychology and social control The issue of social control in society When we talk about social control, we talk about using psychological understanding to control people, either for the good of society or for other reasons. This is an ethical issue, and questions such as Who should have the power to control someone s behaviour? and What are appropriate means of control? arise, and will be tackled in this section for each of the four elements of social control you need to know about. There are also practical issues involved, which will also be discussed for each of the following areas. Use of drug therapy Drug therapy may be used to help people who are depressed to control their mood disorder, or to help combat the symptoms of schizophrenia, but drugs have many widespread uses beyond this too. The use of drug therapy has been seen as very positive in some areas, but also some psychological studies show it in a negative light, such as Rosenhan (1973). Drugs may also be used to overcome drug dependency. Ethical issues should drug taking be a free choice, and who has the power to control someone s behaviour with the use of drugs against their will? This can be observed within mental institutions where patients are made to take drugs. Also, generally, adults have the right to make their own decisions, but the problem arises when they are unable to make that decision, so who should decide what is right for the patients family, expert clinicians, etc when is social control with the use of drugs appropriate? Are patients in mental health institutions given drugs to control their disorders because it is for their own good, or is it for the convenience of the staff members? likewise, is drug therapy the most effective treatment for such conditions? For example, a GP may prescribe antidepressants to someone with depression for the GP s own convenience, but perhaps CBT should be offered development of drugs usually involves animal testing, which raises its own ethical concerns a further ethical issue is whether a (recreational) drug addict should be allowed to continue harmful drug use, or social control should be used to force them into giving up drugs because of the harm caused who has the right to stop people taking these drugs?

4 Practical issues patients may forget to take their drugs, or choose to not take them because they are concerned about the side effects, so this may not be a very effective therapy an issue in itself is that drug use often has the risk of side effects effectiveness may wear off and patients also relapse often when released from drug therapy an addictive person needs to attend regular meetings and agree to counselling to help them move away seamlessly from the peer group without any adverse effects it is generally agreed that drug therapy works best when used with a different type of treatment (such as cognitive-behavioural therapy) which makes it costly and time-consuming patients need to be prepared to make a commitment to the treatment course Use of token economy Based on the principles of operant conditioning, tokens in token economy are rewarded for showing desired behaviours, and undesired behaviours are ignored. The hope is that by these rules, shaping will take effect. In token economy programmes, tokens can be exchanged for rewards the individual wants. A useful study is Hobbs and Holt (1976). Ethical issues TEPs may be used in mental institutions, prisons and schools, but who are the programmes really benefitting the individuals, or the staff? Someone is deciding what the desired behaviours are, and actively forcing participants to show those behaviours, but we have to wonder who has the right to do that the use of TEPs is likely to infringe on rights of the participants, as they are required to change their behaviour (to conform to someone else s will) in order to be rewarded the programmes can be seen as ethical if the target behaviours will benefit society and if the rewards are something which is given on top of the participants usual requirements, but if the reward is something which the participants need (such as a meal, if in a prison) the programmes are considered unethical, as the individuals are forced to change those with a mental health disorder may have very little free will over choosing to participate also seen as controversial is the use of TEPs for profit, such as using store loyalty cards or clubcards, as although they seem to attract custom and offer advantages to customers, the companies benefit from using conditioning techniques Practical issues often the programmes do not generalise when the participants leave the controlled setting, so once the TEP stops and the individual is released from prison, school or the mental institution, the behaviours which were previously rewarded will no longer be rewarded, and so the behaviours might stop also, many individuals will automatically stop showing the behaviours once released from the programme, as their behaviours have not actually changed, but they only showed target behaviours in order to complete the programme staff monitoring the TEP have to be trained which is costly, and the staff also must use the scheme fairly and treat each participant universally in order for it to be ethical and effective a difficulty is implementing a programme which offers rewards which every participant wants the rewards have to be something they desire, or else there is no motivation to show the desired behaviours and effectiveness is reduced Use of classical conditioning The use of systematic desensitisation to treat phobias (and some anxiety disorders), relies on the principles of classical conditioning. This occurs where someone learns to associate an object, which was previously feared and caused a panic response, with relaxation responses, in order to overcome the phobia. Similarly, aversion therapy can be used to associate something undesirable to exhibit an adverse response to something undesired, such as alcohol. Aversion therapy has also been used controversially in the treatment of homosexuality. Ethical issues it is possible that you may have a lot of pressure put on you by the therapist and feel pressured into having the treatment, especially for aversion therapy where an adverse response is being paired to a stimulus (this is common in a prison, where the therapist may pressure the individual by removing their ability to say no or by making them feel they cannot refuse)

5 however, it can be argued that an ethical strength is that aversion therapies have been used to help many overcome undesirable habits and addictions, such as alcohol abuse and smoking addiction a weakness is that it is likely to be an unpleasant experience for the patient, especially if subjected to abuse (for example, when electrotherapy was used to try and cure homosexuality, which in one case led to the death of a man) but again, a strength is that the participants are given some control over the therapy for example, with systematic desensitisation where they develop their own hierarchy of fears so it is more ethical than flooding, for example classical conditioning principles are also exploited in advertising, to make customers respond positively to certain products, which is controversial as it manipulates those subjected to the advertising media to benefit the companies Practical issues participants must be willing to participate, which is one issue, but more importantly a participant must be able to learn to relax so that relaxation responses can be associated with the unpleasant stimulus: unless in times of panic the individual is able to implement relaxation techniques, the therapy is going to be ineffective it requires very little equipment, on the other hand, and the cost is low (except for time investment of the therapist) with aversion therapy, for example used to treat alcohol addiction, the conditioned response should not be generalised to other objects (such as when aversion therapy techniques might involve associating alcohol with a substance that induces vomiting, therefore making the patient less likely to want to drink alcohol but the therapy must be careful not to over-generalise as the individual still needs to be able to drink other liquids without feeling sick) another issue is that generally for these treatments to be effective, a relationship with the therapist needs to be build up, and sometimes these rapports are hard to generate between the client and therapist Influence of the practitioner Evidence suggests that cognitive-behavioural therapy is effective for patients with schizophrenia, depression and anxiety disorders, and it is recommended by NICE. In general, it does not raise the same ethical and practical issues as other therapies, as it has no biochemical side effects (unlike drug therapy) and does not cause the level of distress treatments such as systematic desensitisation can. However, the therapist is still able to exert control over an individual through the tasks and challenges set, although again this is not as significant as with other therapies as like with systematic desensitisation, the therapist works with the patient, and so the patient is given a little more control. Whilst psychodynamic therapies might be moderately successful for some conditions, despite a lack of theoretical underpinning, they have the potential for misuse as the therapist has such power over the patient. For example, the case study of Beth Rutherford can be used, where her therapist implanted false memories of her father sexually abusing her when she was younger, claiming she had used defence mechanisms to forget the memory, which in fact, never happened. As for with drug therapy, those prescribing and administering the drugs will have power, and this includes with regard to addiction to the drug. The practitioner has some power over addicted patients, but the patients themselves can choose whether or not to attend treatment sessions. Society also has power with regard to this treatment, as a court order may specify that an individual must attend drug rehab therapy sessions. The practitioner also has power in choosing which drugs are appropriate and whether or not an individual is in need of drug therapy. However, since most individuals return to drug use having completed a session, it is suggested that they ultimately have the real power, not the therapist. Staff running and implementing token economy programmes have power over the individual, this goes without saying. They can withhold a token at any time, for example, if the programme is not properly supervised. The individuals in these programmes do not have much power, because the programme is usually run within a private, closed institution where the participants are unlikely to gain consent not to participate or to withdraw from the programme. The therapist of classical conditioning therapies who conditions the desired behaviours is in a position of power, as are other therapists. They might be controlling the aversive stimulus in the case of aversion therapy, and with systematic desensitisation they control the hierarchy after it has been decided, although it should be acknowledged that in developing the hierarchy, the therapist works with the patient to develop a scheme which will work towards a desired goal. Also, the client has to agree to the therapy and has the opportunity to withdraw at any time they cannot be pressured or forced into the therapy and this reduces the power of the therapists for treatments using classical conditioning.

6 Different types of power French and Raven (1960) distinguished five different types of power. A therapist from most treatments possesses most of these types of power: expert power is given to someone who is an expert in the field, having knowledge in a specific area of study reward power is held by the therapist because they can reward the client with praise of rewards, such as tokens legitimate power is given to the therapist because the role of the therapist is to shape the behaviour of the participants, and society has certain expectations regarding how people should behave which meet the therapist s targets coercive power should not be held by therapists, as this involves punishing others, although society might pass coercive power onto a therapist, for example by sectioning someone (under the Mental Health Act) or ordering somebody to have anger management training or drug rehab therapy as a condition of a court case referent power might be endowed onto a therapist by a client because the client transfers feelings of admiration onto the therapist who is seen as having the skills and knowledge the client wants (referent power was described by French and Raven as the power given to someone because someone else would like to be like them) Psychology and cultural issues Ethnocentrism Ethnocentrism is a bias, and is the tendency to focus on one s own culture. Ethnocentrism is the idea that we view our world through our own frames of reference and schemas so we cannot see from another person s viewpoint (schemata refers to Bartlett (1932) who looked at reconstructive memory and suggested culture-based schemata, ideas from cultures which were individual interpretations of aspects of life). A culture or society has a strong frame of reference involving norms, rules, customs, habits and preferences. We see other cultures through our own eyes, and think that our view is right. This is thinking we are right about ethnocentrism. Ethnocentrism introduces bias in the findings of psychological studies. It is useful to know about ethnocentrism so that we can try to understand the views of other cultures, in order to try and eliminate that bias. Bias may be in that: - biased in terms of diagnosis, for example when diagnosing schizophrenia, we need to use cultural relativism, making the diagnoses more relevant to the culture - biased in terms of client-centred therapies, such as cognitive-behavioural therapies or psychodynamic therapies, which rely on having non-judgemental relationships with your client you have to accept their view of the world Researchers tend to focus on investigation phenomena related to their own ethnic group, which leads to two problems: - a lack of balance in research, as much is based on westernised ideas - a lack of generalisability in the findings, such as with the DSM, ideas based on research may be inappropriately applied Cross-cultural research Research across different cultures can be useful in showing whether a characteristic is universal or unique to a particular culture. This makes cross-cultural studies useful for contributing towards another of the debates, the nature-nurture debate. This is because the characteristics which are found to be universal (i.e. the same across all cultures) are more likely to be down to human nature, and those which are found to be different or unique to a culture are more likely to be down to nurture and the environmental influences surrounding that culture. Cross-cultural research takes a hypothesis and methodology and tests them in different cultures. Ainsworth and Bell (1969) used the strange situation to look at attachment types and found similarities between the Ugandan and USA studies. Researchers took the procedure and replicated it in other cultures, finding similar results in some, and very dissimilar results in others. Having similar findings in very different cultures gives them generalisability as a universal characteristic has been found. Viewing secure attachments (type B) as the best and right attachments is a very ethnocentric view, just because the UK and USA have the majority of children and mothers with these attachments. It can be said by analysing research into attachment types that the process of forming attachments is down to human nature, as all mothers and their children form attachments of some sorts across all cultures. However, attachment types must be influenced heavily by environment and are down to nurture, because results of studies using the strange situation procedure differed from culture to culture.

7 Taking the example of attachment types, we can explain the cultural differences by looking at the views of different cultures. For example, in Germany, Grossman and Grossman (1975) found that there were very few securely-attached children, and mainly anxious-avoidant (type A). It was not suggested that German mothers were insensitive to their babies needs, but just that they encouraged independence. Etic and emic approaches There are a number of different ways of conducting cross-cultural research. An etic approach can be used whereby similarities are looked for between cultures, by studying each culture as an outsider. This would involve the outsider researcher using tools and techniques which have been developed in their own culture, using westernised ideas, and these may not be equally valid in the other cultures. An example would be replicating the strange situation in nonwesternised countries. An etic approach introduces much bias to a piece of research. Alternatively, an emic approach might be used, whereby the focus is on an individual culture from the perspective of an insider. An example might be Malinowski (1918) who used ethnography (immersing himself into another culture to try and gain a complete understanding of it and to avoid ethnocentrism), to study the people of Papua New Guinea and the Trobriand Islands. This researcher was a pioneer into ethnographic research, but ethnography has certain problems. It is all very well and good a researcher trying to immerse themselves into a culture to view things from an insider s perspective, but we have to consider how well anyone is really ever going to become an insider. Firstly, they are never going to be treated like an insider by people who already belong to that culture. Also, you cannot completely understand a culture without really being a part of it, which makes it seemingly impossible to truly understand another culture. However, it is still seen as stronger than an etic approach. Social constructionism The concept of social constructionism illustrates a weakness of cross-cultural research: if something is scientifically proven, it should be true of all people in all cultures and is likely to come from nature social constructionism suggests though that many features, concepts and ideas in human societies different between cultures, and therefore social constructs (such as gender appropriate behaviour and laws within the culture) are likely to affect cross-cultural research, and therefore although the same concepts might be being studied across cultures, they may not always have the same meaning and significance associated with them furthermore, the appropriateness of the methodology used, such as the strange situation, affects the validity of the findings Evaluation of cross-cultural research The main strengths and weaknesses for cross-cultural research are: Cross-cultural research is the only way to identify differences and similarities between differing cultures, so that universal behaviours and characteristics can be discovered: this contributes towards the nature-nurture debate It can also identify different approaches to issues in differing cultures, so allowing the transfer of techniques between different cultures, although this can be difficult (for example with diagnosis using the DSM) Although the same methodologies may be used to test the same concept across different cultures, they may be more appropriate in some cultures than in others, such as with the strange situation task There may be ethnocentric bias from the researcher or analyst reading the research or analysing the results of a piece of cross-cultural research, as they use subjective thoughts from their own culture s concepts and schemata, for example with the strange situation, which infers that secure attachments are the best type, German children were found most often to be insecurely attached, but this is just because their children were encouraged to be independent, not because they have worse ways of forming attachments with their children Nature-nurture debate Nature and nurture Essentially, the nature-nurture debate comprises two arguments: characteristics individuals are born with (and so are genetically predetermined and down to nature) and those which individuals learn from interaction with the environment (and so are down to nurture).

8 Nature refers to what we are born with, including any processes that develop as we mature, and any effects on ourselves as an organism before birth these are genetically predetermined features. It is part of our biology and our evolution. Human beings are genetically programmed to look certain ways, behave in certain ways and die in certain ways. Our chromosomes are all similar, and our sex is determined by the non-autosomal chromosomes, either XX or XY. Our genes dictate the release of hormones, and these hormones dictate our human biology. Neurotransmitters also send messages around our brain and between neurones of the nervous systems. Our brains also play a part in our behaviours, for example, the amygdala is involved in generating emotions in the brain. Nurture refers to the effect of our environment and our experiences on us as we develop and grow. The biological environment that affects us before birth and after conception is still part of nature, but all other environmental influences are considered the nurture side of the argument. Nurture is concerned with all external influences, such as family and peers. It is about learning through interaction and experiences with the environment, and socialisation processes. Studying the debate There are a number of methodologies used to study the nature-nurture debate: twin studies these can be used to easily identify what has a nature basis, and what has a nurture basis, by studying both monozygotic (identical) and dizygotic (non-identical) twins, as MZ twins share 100% of their DNA (whereas DZ twins only share half their genes). Using twin studies, we can identify genetic links between twins by looking at concordance rates to see to what extent certain characteristics have a biological basis. Interestingly, there is no characteristic which has a constant 100% concordance rate across all MZ twins (even though they share 100% of their genes), which suggests no matter how biological something may be, environment always plays an influential role adoption studies these studies work in the other way we can use these to show the environmental influences on characteristics, and likewise where something is seen to not be affected by environment, we can suggest it is down to nature (for example, if a child is adopted and lives totally excluded from their genetic family, and his biological father has schizophrenia, and the child develops schizophrenia, we call this evidence that there is at least some biological cause for schizophrenia) animal experiments animals can be bred specifically that are 100% genetically-identical, and studies on these animals will show to what extent the environment has an effect on certain characteristics, as with twin studies cross-cultural studies these again can also help to show what characteristics in humans are innate and which are learned, for example, if attachment patterns between mothers and babies are the same across all cultures, then it might be concluded that human infants have an innate tendency to form an attachment with a caregiver (link into the debate of psychology and cultural differences) The interactionist view The nature-nurture debate is not clear-cut. For example, after conception, the womb is an environment that gives the foetus experiences (for example stimuli such as the mother smoking or drinking alcohol, and also noises heard from outside the womb). After birth, developmental (biological) maturation occurs, and so biological influences do not stop at birth. The interactionist view takes these elements into account. How approaches and applications answer the debate Each of the approaches to psychology and applications of psychology from AS and A2 have theories, concepts and studies which approach the nature-nurture debate differently. They all have different views about the nature and nurture side of the argument, of course the two approaches with the heaviest weighting are the biological approach (nature) and the learning approach (nurture). The grid on the following page describes how each approach and application answers the debate.

9 Social approach Cognitive approach Psychodynamic approach Biological approach Learning approach NATURE Perhaps that people have evolved to act as agents in society Information processing in the brain takes place in a certain way and brain structures serve different functions with regard to thinking People have the id, ego and superego and are guided by unconscious forces Hormones, neurotransmitters, genes and brain structure link with the genetic blueprint, as do maturational processes Reflexes are innate, as is the tendency to learn by association and reward (learning methods are innate we are born with them) NURTURE Focuses on how society affects people, including the interactions of in-groups Cues in the environment are used to help us remember, and how we encode something from the environment can affect forgetting or recall Parents and societies give the superego and conscience and so we learn to fit with society The environment from conception onwards affects maturation and development of the human being What we learn, however, comes from our interaction with the environment, including all of our experiences Child psychology Babies are born with a tendency to form attachments and to develop language, amongst other innate features Environment, such as privation and deprivation, affects development different experiences lead to different developmental and maturational experiences Criminological psychology Clinical psychology Can include whether someone is born a criminal, perhaps linked to aggression and brain structures and hormones Mental health disorders have biological bases, such as schizophrenia and depression, where they may be an element of heredity Includes the effect of the environment on becoming a criminal, such as social learning theory and self-fulfilling prophecy concepts Mental health issues could be affected by the environment, for example, those with social support seem to be less affected Evaluating nature-nurture explanations When evaluating explanations of behaviours or characteristics that draw on the nature-nurture debate, the research methods used to gather data can be evaluated for either nature, nurture or interactionism. For example, if there are two MZ twins, one of whom has schizophrenia, we cannot conclusively predict that the other will have the same disorder. Whilst evidence suggests there is a biological explanation, concordance rates are never 100% suggesting nature plays at least a small role. Because researchers find it difficult to become completely immersed into another culture, and tend to have ethnocentric bias when analysing or researching, cross-cultural studies are often hard to draw conclusions from. Animal studies can help to draw conclusions about human behaviour, but animals are different from humans in important ways, as you will know from evaluating animal studies and their practical issues. This makes it hard to generalise the findings from such animal studies to humans, so you cannot conclusively say something is solely nature-dependent simply by using animal studies other areas of research are essential to make the argument more convincing.