Slides in this set
The biological approach is concerned with how our genetic inheritance, evolution of the human species and
the nervous system affect how we think, feel and behave
1.Central nervous system especially the brain plays an essential role in our emotions and behavior, need to
understand structure and function. Abnormal behaviors results from physical damage especially to the brain,
e.g. a stroke to the brain cause a blockage in the arteries and a lack of oxygenated blood can lead to atrophy of
the neurons which will not send a message.
2. Behavior is influenced by genes which could be intelligence or an illness. E.g. a human inherits 23
chromosomes from each parent, a recessive gene that can be inherited can cause a disorder called PKU which
decays the neurons from a young age as the enzyme causes irreplaceable damage to the CNS.
Seyles General Adaptation Syndrome:
Model of stress based on body's physiology and psychobiology after studying rats.
First stage: alarm stage threat detected, message sent to brain to activate sympathetic part of
autonomic nervous system.
Second stage: resistance stage body's attempt to return to a steady state, despite persistent stressor.
Final stage: exhaustion stage failure of body to return to normal state due to persistent stressor leads to
Biological therapy: chemotherapy, use of drugs to influence emotions, behavior.
1. Mimic neurotransmitter, prolong transmitter action, block receptors.
2. To relive symptoms.
3. To help make other treatments more successful.
4. In depressed people levels of serotonin are low compared to non depressed people. A drug
SSRI(serotonin reuptake inhibitors) block return of serotonin into the pre synaptic knob,
remains in cleft increasing likelihood of attaching to receptors and increasing serotonin
5. Schizophrenia linked to high level of dopamine, drug treatment block dopamine receptor
sites, reduces symptoms.
Strengths: 1.drugs produce rapid reduction in symptoms. 2. removes the need of harsh
treatments to control people with severe mental illness.
Weakness: 1. do not treat underlying problem, only symptoms. 2. side effects and unethical.
Link back to assumptions
Communication between neurons, possible to use other chemicals(drugs) to affect brain
Different drugs have different affects on different neurotransmitters.…read more
Methodology: lab experiments on animals
Systematic testing of many animals under controlled conditions, they are exposed to a range of
procedures. Studies test effect of independent variable to dependant variable.
Examples: 1. seyles effect of stressor on animals health. 2. compare animals to control groups.
3. drug effects may be tested on animals
Methodology : twin studies
Looking at similarities and differences between genetically identical people. Researchers investigate a trait they are interested in.
Measure two people on this and find a correlation . Also compare identical twins with non identical twins.
Example: Gottesman (1987): found that DZ have 17% concordance rate whereas MZ have 44.8% for schizophrenia
Evaluation: lab experiments Evaluation: twin studies.
Advantages Disadvantages Advantages Disadvantages
Variables can be controlled, the systems are still very High ecological validity, little often twins are raised in the
increases validity because different , brains are also manipulation of IV, just a same environment, will be
changes in DV less likely to different in size and measurement. difficult to separate the
be from extraneous structure. effect of nature and nurture.
range of procedures can be Unethical to conduct Allows psychologists to make Twin studies not
used, not allowed on experiments on animals to assumptions about experimental , can not
humans gain benefits for humans. importance of genes. establish cause and effect.
Many animals could be used Lack of realism biological
MZ twins share 100% genes,
which increase reliability of process change in real
any difference will be from
results, a nomothetic surroundings.
Evaluation of biological approach:
1. The methods used by the biological approach give its studies a high degree of reliability,
validity and scientific credibility, which is enhanced by its focus on objectively observable
experiences rather than subjective ones.
2. If we know the physiological basis of some aspects of behaviour (e.g. depression)then we
can treat the problem using drugs, which could solve the problem entirely if it's simply a
straightforward chemical imbalance. Plus, some aspects of physiology and anatomy are very
useful when it comes to diagnosing brain damage etc.
3. Explanations from the approach have useful applications.
1. The biological approach can be to simplistic, some illnesses are far too complex e.g.
depression and schizophrenia. Difference in symptoms between individuals may mean
treatment of one patient can be used for another as it may be ineffective.
2. Chemotherapy only treats symptoms not the underlying cause.
3. Difficult to separate genes and environmental influences on behavior.…read more