Discuss the Biological Approach in Psychology Essay

Discuss the biological approach in psychology. Refer to at least one other approach in your answer. (12 marks) The biological approach focuses on both the physiological and evolutionary aspects which explain human behaviour. The causal level of analysis incorporates physiological explanations, such as the effect of nerves and hormones on behaviour. According to biological psychologists, behaviour is controlled by the nervous system, which consists of the central nervous system (the brain and the spinal cord) and the peripheral nervous system (the surrounding nerves), which itself includes the autonomic nervous system that controls automatic processes such as heart rate and the fight or flight syndrome. Within the central nervous system, neurons communicate with each other via sending chemical impulses, neurotransmitters, across synapses. Biopsychologists believe that these chemical processes in the brain directly influence human behaviour. Too much or too little of these chemicals ca n result in over-activity or under-activity in various parts of the brain; this alters thoughts, emotions and behaviour. For example, a link has been made between excessive dopaminergic activity in the brain and the incidence of schizophrenia. Pearlson et al (1993) used Positron Emission Tomography (PET) scans and found a substantial increase in D2 receptors in patients with schizophrenia. Seeman et al (1993) also used PET scans, finding six times the density of D4 receptors in the brains of schizophrenic individuals. A limitation of such studies is the idea of cause and effect; for example, it is unclear whether the increase in dopamine receptors causes schizophrenia or is a result of the neuroleptic drugs taken. Yet, Pearlson’s study was carried out on individuals who had not been exposed to neuroleptic drugs, which therefore rules out cause and effect. Neuroimaging studies are able to study the structure and functioning of the brain, and have the advantage of being non-invasive. Researchers have shown how behaviour can be affected by different levels of sex hormones, for example increased tes tosterone has been linked to aggression and increased risk-taking. In forensic psychology, Eysenck’s theory of the criminal personality suggested that individuals who offend are high on the extroversion dimension and seek constant stimulation and autonomic arousal from their environment. These individuals are also said to be high on the neuroticism dimension, with high anxiety levels and an emotionally unstable central nervous system. Their nervous system reacts strongly to aversive stimuli and, as a result, these individuals cannot effectively learn socially appropriate behaviours. Eysenck’s theory is criticised for inconsistencies between criminal activity and extroversion. Zuckerman (1969) also argued that environmental stimulation may be sought as a result of boredom, where there is increased arousal. Behaviourists also emphasise the role of the environment as a determining factor of behaviour in the nature versus nurture debate. The behaviourist approach states that all individuals are born with ‘blank slates’ (tabula rasa), with behaviour being learnt through the process of conditioning, past experiences and the environment. With reference to the forensic psychology topic, neo-behaviourists argue that criminal behaviour is learnt by observing and imitating the behaviour of role models in the environment, e.g. peers, celebrities, novel characters. The imitation of aggressive behaviour is most clearly shown in studies conducted by Bandura et al (1963), in which children who observed models performing aggressive acts on a Bobo doll later displayed this same behaviour. However this experiment is criticised for being open to demand characteristics so the children knew what was expected of them, which confounded the results (Cumberbatch, 1992). In contrast, the functional level of analysis focuses on evolutionary and genetic theories of behaviour. In the 1800s, Charles Darwin postulated the evolutionary theory which put forward the idea of survival and reproduction as an important feature of behaviour in all species. In what he called the ‘survival of the fittest’, Darwin suggested that through th e process of natural selection animals with particular characteristics, as a result of possessing advantageous alleles, will survive. However, those with maladaptive genes cannot adapt to changes in environmental conditions, so will die or become extinct. Dowling (1994) stated that this process depends on three principles: species diversity, interaction and the spread of a species as a result of differential amplification. Sexual selection is another component of Darwin’s research, which explains the best strategies adopted for passing on genes to offspring. Moreover, there are problems with Darwin’s theory such as his attempts to generalise animal behaviour to the way in which humans interact in their environment. However, he has presented compelling evidence which is very scientific in its approach and methodology. Furthermore, contrary to Darwin’s evolutionary idea of survival of an individual, Dawkins (1976) suggested that the survival of the genes is more important. Schizophrenia twin studies have found a 46% concordance rate for monozygotic twins compared with a 14% concordance for dizygo tic twins. This high concordance suggests the contribution of genotype to the onset of schizophrenia, yet the 40% discordancy indicates that environment must play a role in the development of this condition. Moreover, localisation of function explains how different parts of the brain have particular functions; for example, the amygdala has been linked to aggression. A more famous example is the HM case study, in which an operation on his brain, in order to treat severe epilepsy, resulted in anterograde amnesia. The removal of HM’s hippocampus was therefore linked to his amnesia upon recovery, where he could not form new memories. Chromosomes are made up of genes which produce a phenotype, dominant or recessive. Abnormalities in chromosomes have been found through biological research. For example, Kleinfelter’s syndrome and Turner’s syndrome both comprise an atypical chromosomal pattern which, in turn, produces abnormal behaviour. Male individuals with Kleinfelter’s syndrome have the XXY chromosomal pattern, in which they possess an extra X chromosome; symptoms include broader hips and reduced fertility rates. Turner’s syndrome involves the absence of an X chromosome in females, resulting in webbed necks and memory deficits. Furthermore, criminal research has found an incidence rate of 0.1% XYY pattern in the ge neral population, with 1.5% XYY in the prison population, suggesting that atypical chromosomal patterns cause criminal behaviour. Yet, further studies have failed to confirm this link; Wilkin et al (1976) found that only 12 men in a large sample of 4500 males had the extra Y chromosome, with none being an offender. This theory was consequently refuted. The biological approach as provided a lot of evidence for the biological basis of behaviour, yet it tends to be deterministic, seeing free will as an illusion. The humanistic approach, however, believes that we are active agents and able to choose our behaviour. In addition, the biological approach is reductionist and dehumanising as it reduces all behaviour to biological processes, such as genes and neurochemicals. In contrast, both the humanistic and psychodynamic approaches are holistic to some extent. The humanistic approach emphasises the whole person and whole subjective experience, whilst the psychodynamic approach concentrates on the individual’s life. A method used in much of biological research is the use of laboratory studies. These are high in control, yet lack ecological validity as the findings cannot be generalised outside such a controlled environment. Similar to the biological approach, the behaviourist approach uses scientific methods which are falsifiable and objective. For example, operant conditioning was studied by Skinner in a series of experiments with rats who, when by chance, pressed a lever received a pellet of food. Through positive reinforcement, they continued to press the lever in order to increase the likelihood of the desired response being repeated (receiving food). However, the use of animal studies means that findings may lack generalisability to human behaviour; although, Darwin would disagree as human and animal anatomy and behaviour are seen as similar. Debates that arise in biological research include the concept of determinism. This is shown in biological research as free will is often ignored and consequences are seen as beyond human control. Biological theories are reductionist as they attempt to explain human behaviour by breaking complex processes down into fundamental biological ones. This approach is criticised for focusing only on the nature side of the nature vs. nurture debate; it is believed that behaviour is innate and therefore environmental factors and cognitive mediating processes are ignored. Furthermore, the biological approach is nomothetic as the features that people have in common are investigated and general laws of behaviour are applied to groups. Empirical studies are mainly objective as they observe phenomena rather than focusing on subjective experiences, like behaviourists tend to do. Yet this is also a limitation as it is argued that biopsychologists dehumanise and neglect the importance of experiences. Humanistic psychologists argue that the subjective experience is important as we are motivated to achieve self-actualisation (Maslow, 1987). Practical applications of the biological approach have been useful and effective in society. Drug therapy has been developed in order to treat illnesses and disorders, such as schizophrenia. Anti-psychotic drugs include risperidone, clozapine and chlorpromazine. Atypical drugs, clozapine and risperidone, also treat negative symptoms of schizophrenia. For depression, drugs include Selective Serotonin Reuptake Inhibitors (SSRIs), Monoamine Oxidase Inhibitors (MAOIs) and Tricyclic anti-depressants. Bipolar disorder can be treated with Lithium Carbonate, which is toxic but, unlike the drugs for unipolar depression, they treat the manic phases of the disorder also. Where drug therapy may not work in specific cases, electroconvulsive therapy (ECT) is used; as this involves inducing an electric shock on the patient’s brain this therapy can be seen as unethical, especially in cases where this treatment is given against a patient’s wishes. However, it is still used today and has proven to be effective. Drug therapy itself has been criticised for only prevention and not curing symptoms. Side effects, such as clozapine lowering the white blood count, and the long period it takes for an effect can both result in a lower adherence to this particular treatment so relapse is common. A problem arises when schizophrenic patients may discontinue use due to the side effects and long time to feel any effect. Invasive and non-invasive techniques are used to identify which brain areas may responsible for types of behaviour. Using invasive techniques, such as lesions and abrasions in brain surgery, biological psychologists have identified Broca’s area which controls the production of speech. In contrast, behaviourists tend to use cognitive-behavioural therapy for illnesses and disorders, such as depression, which has been found to be more effective than medication (Elkin et al, 1985). In conclusion, the biological approach has contributed a huge amount to how we explain human behaviour. There has been much empirical research and the applications have enabled individuals to live normal lives that they had previously not been able to. However it is more advisable to take an interactionist approach as the role of nurture must be considered where behaviour is concerned.