Biological approach Flashcards
BIOLOGICAL: What are the assumptions?
- the physiological approach: this approach believes that all behaviour is due to the functioning of internal body parts, for example the brain, nervous systems, hormones and chemicals.
- the nativist approach: this is based on the assumption that all behaviour is inherited; behaviour is passed down through our genes from one generation to the next.
- the medical model; this refers to the treatment of psychological disorders based on the same principles used to treat physicals diseases. The argument is that psychological problems ultimately have a physical cause and thus can be treated using physical (medical) methods.
ASSUMPTION 1: EVOLUTIONARY
- genetically determined behaviour that enhances an individual’s chance of survival and reproduction will be naturally selected (genes passed onto next generation)
- EG altruistic behaviour; parents risk their lives to save their offspring. the theory of natural selection would say that altruism is an inherited, adaptive trait because saving an offspring enhances the survival of that individual’s gene pool.
ASSUMPTION 2: LOCALISATION OF BRAIN FUNCTION
- certain areas of the brain are responsible for different functions
- Frontal lobes are involved in thinking and creativity, and are linked to our personalities
- parietal lobes receive sensory information such as temperature, touch and pain.
- temporal lobes are responsible for much of our memory
- occipital lobes are concerned with visual processing and receive information directly from the eyes
- localisation of language:
- french neurologist paul broca studied 8 patients with language problems. he examined their brains after death to find they had damage to an area in their left hemispheres, known as broca’s area, and is associated with speech production.
ASSUMPTION 3: NEUROTRANSMITTERS
- neurons are electrically excitable cells that form the basis of the nervous system. the flexibility of the nervous system is enhanced by having many branches at the end of each neuron (called dendrites) so that each neuron connects with many others.
- One neuron communicates with another neuron at a synapse, where the message is relayed by chemical messengers (neurotransmitters). There is a diagram of a synapse on the following spread. These neurotransmitters are released from presynaptic vesicles in one neuron, and will either stimulate or inhibit receptors in the other neuron, the synaptic cleft or gap is about 20nm wide.
STRENGTHS: scientific approach
- behaviour can be explained in terms of the brain, neurotransmitters and localisation of brain function. this means biological explanations have clear variables that can be measured, tracked and examined. this enables psychologists to conduct scientific research to research studying these variables.
- Raine et al. made use of PET scans to compare 14 areas of the brain in murderers (pleading NGRI) compared with non murderers.
- Research on drug therapy has investigated the links between psychoactive drugs and the production of certain neurotransmitters (such as dopamine), and linked this to behaviour.
STRENGTHS: determinist approach
- one strength of this approach being determinist is that if we know what predetermines our behaviour, we are more likely to be able to treat people with abnormal behaviour.
- for example, the neurotransmitter dopamine has been linked with the mental disorder of schizophrenia. the evidence that comes from a number of sources. the drug amphetamine is known to increase levels of dopamine and the large doses of the drug can cause some symptoms associated with schizophrenia. a second line of evidence is that antipsychotic medications reduces the dopamine levels of these schizophrenic patients and thus this suggests that high levels of dopamine are causing the symptoms.
STRENGTHS: successful applications
- the biological approach has led to many successful applications.
- research into the relationship between abnormal levels of neurotransmitters and criminals, leading to lowered recidivism rates, and ultimately safer societies. for example (cherek et al.2002) showed that males with conduct disorder and criminal behaviour had reduced levels of aggression and impulsivity after a 21 day course on an SSRI antidepressant compared to a control group on placebos.
WEAKNESS: reductionist approach
- biological explanations reduce complex behaviours to a set of simple explanations, for example reducing the experience of stress to the action of the hormone of adrenaline.
- reductionism is a part of understanding how the systems work, but the problem is that in the process we may lose a real understanding of the thing we are investigating.
- for example, the biological approach suggests that schizophrenia is basically a complex physical chemical system that has gone wrong. the psychiatrist R.D Laing (1965) claimed that such an approach ignores the experience of distress that goes along with any mental illness, and is therefore at best an incomplete explanation.
- a simplified explanation may prevent us reaching a true understanding of the target behaviour.
WEAKNESS: nature rather than nurture
- mental illness has multiple causes, yet the biological approach focuses on just biology (nature), it doesn’t acknowledge life experiences (nurture)
- for example, the biological approach is only concerned with abnormal levels of neurotransmitters rather than with ho patients feel about their illness.
WEAKNESS: individual differences
- the biological approach is a nomothetic approach, looking to make generalisations about people and find similarities. it tends to ignore differences between individuals. for example when stressed, some people produce higher levels of adrenaline than others, which, in turn, affects the long term effects of stress.
- biological research focuses on just a few individuals and assumes that everyone’s biological systems behave in the same way.
- for example, Taylor et al. 2000, suggest that men usually react to stress with a flight or fight response, tend to show a tend and befriend response. this gender difference is seen in many species, with females responding to stressful conditions by protecting and nurturing their young (tend) and seeking support from other females (befriend) the difference is attributed to women producing the hormone oxytocin when stressed, sometimes called the love hormone.
What are the 3 biological assumptions?
- evolutionary
- neurotransmitter
- localisation of brain function
What are the three strengths of the biological approach?
- scientific
- determinist
- successful applications
What are the three weaknesses of the biological approach?
- reductionist
- nature rather than nurture
- individual differences
What are the main components of Drug therapy?
Antipsychotic drugs: - antipsychotic drugs treat psychotic mental disorders such as schizophrenia. A patient with a psychotic mental disorder has lost touch with reality and has little insight into his or her condition. Conventional antipsychotics are used primarily to combat the positive symptoms of schizophrenia (delusions etc), These drugs block the action of the neurotransmitters dopamine in the brain by binding to, but not stimulating, dopamine receptors.
Antidepressants: Depression is thought to be due to insufficient amounts of neurotransmitters such as serotonin being produced in the nerve endings (synapse). In normal brains, neurotransmitters are constantly being released from the nerve endings, stimulating the neighbouring neurons. To terminate their action, neurotransmitters are reabsorbed into the nerve endings and are broken down by an enzyme . antidepressants work either by reducing the rate of absorption, or by blocking the enzyme that breaks down the neurotransmitters. Both of these mechanisms increase the amount of neurotransmitter available to excite neighbouring cells.
Antianxiety drugs:
- the group of drugs most commonly used to treat anxiety and stress and benzodiazepines (BZs). They are sold under various names like librium and valium. BZs slow down the activity of the central nervous system. They do this by enhancing the activity of GABA, a biochemical substance that is the body’s natural form of anxiety relief
Evaluate the effectiveness of Drug therapy?
- Soomro et al. (2008) reviewed 17 studies of the use of SSRI’s with OCD (which has a component of depression) patients and found them to be more effective than placebos in reducing the symptoms of OCD up to three months after treatment i.e in the short term.
- While drugs are extremely effective in treating psychological disorders, many have serious side effects, for example SSRI’s can cause nausea, headache and insomnia.
- One of the common criticisms of of drug therapy is that, while drugs may be effective in treating the symptoms of psychological disorders, this type of therapy does not address the underlying cause.
- relative to other treatments (psychotherapy), drug therapy is cheap for the patient – in the UK they would be prescribed their drugs on the NHS. the practitioner has to invest less time in the patient, because they only need to meet with the patient every couple of months after initial consultation to discus whether the drugs are having a positive effect and whether the patient is making progress.
