the biological approach

Question 1

what is the definition of the biological approach?

Answer 1

a perspective that emphasises the importance of physical processes in the body such as genetic inheritance and neural function.

• it views humans as biological organisms and so provides biological explanations for all aspects of psychological functioning

Question 2

what is the definition of genes?

Answer 2

a part of the chromosome of an organism that carries information in the form of DNA

Question 3

what is the definition of genotype?

Answer 3

• the genetic makeup of an individual
• it is a collection of inherited genetic material that is passed from generation to generation

Question 4

what is the definition of phenotype?

Answer 4

• the observable characteristics of an individual
• this is the consequence of the interaction of the genotype with the environment

Question 5

what is the definition of neurochemistry?

Answer 5

it is the study of chemical and neural processes associated with the nervous system

Question 6

what is the definition of natural selection?

Answer 6

the process by which inherited characteristics that enhance an individual’s reproductive success (or fitness) are passed onto the next generation, and so become more widespread in the population overtime

Question 7

what is the definition of evolution?

Answer 7

the changes in inherited characteristics in a biological population over successive generations

Question 8

what is the definition of biological structure?

Answer 8

an arrangement or organisation of parts to form an organ, system or living thing

Question 9

assumptions of the biological approach

Answer 9

• everything psychological is at first biological
  > to fully understand human behaviour, we must look to biological structures and processes within the body
• if we can explain behaviour through biological factors, then mental illness or undesirable behaviour can be eliminated or cured using biological techniques such as surgery or medicine
• as DNA, and large amounts of bodily structure and function, is universal between organisms, animal studies can be used to inform us of human body structure, chemistry and function

Question 10

the neurochemical basis of behaviour

Answer 10

• much of our thought and behaviour relies on chemical transmissions in the brain
  > this occurs using neurotransmitters
• an imbalance of neurochemicals in the brain has been implicated as a possible cause of mental disorders
  > eg. low levels of neurotransmitter serotonin in OCD and overproduction of dopamine in schizophrenia

Question 11

the genetic basis of behaviour

Answer 11

• twin studies are used to investigate whether certain psychological characteristics have a genetic basis
  > this is achieved by analysing concordance rates (the extent to which twins share the same characteristics)
• if a characteristic is genetic, we would expect all monozygotic twins to be concordant
  > the same would not be true for dizygotic twins who share about 50% of the same genes

Question 12

genotype and phenotype

Answer 12

• phenotype is the way that genes are expressed through physical, behavioural and psychological characteristics

despite having the same genes, identical twins have different phenotypes
> this illustrates that much of human behaviour depends upon an interaction between inherited factors (nature) and the environment (nurture)

Question 13

evolution and behaviour

Answer 13

• charles darwin proposed the theory of natural selection to explain evolution
• the main principle of this theory is that any genetically determined behaviour that enhances an individual’s survival will continue in future generations
• in nature, this selection takes place ‘naturally’ so no one ‘decides’; it occurs simply because some traits give the possessor certain advantages which means they are more likely to survive and reproduce and pass on these traits
• if the individual survives but does not reproduce, the traits do not remain in the gene pool for successive generations

Question 14

describe 5 ways in which we can examine the brain in more detail and what they do

Answer 14

1. PET scans - show which parts of the brain are active when different tasks are carried out, but can only show averages over a period
2. CAT scans - show damaged parts of the brain eg. tumours or blood clots
3. MRI scans - provide detailed structural information about the brain
4. fMRI scans - provide detailed structural and functional information about the brain
5. SQUID magnetometry - provide accurate real-time images of brain activity, but are delicate and easily distorted

Question 15

evaluation: real world application

Answer 15

• increased understanding of neurochemical processes in the brain is associated with the use of psychoactive drugs to treat serious mental illnesses
• biological approach has promoted the treatment of clinical depression using antidepressant drugs that increase levels of the neurotransmitter serotonin at synapses in the brain
• this means that people with depression may be better able to manage their condition and live their lives in the community, rather than remain at hospital

Question 16

evaluation: scientific methods

Answer 16

• biological approach makes use of a range of precise and highly objective methods, such as fMRIs and EEGs
• with advances in technology, it is possible to accurately measure physiological and neural processes in ways that are not open to bias
• this means that much of the biological approach is based on objective and reliable data

Question 17

evaluation: drugs do not work for everyone

Answer 17

• andrea cipriani et al. (2018) compared 21 antidepressant drugs and found wide variations in their effectiveness
• although most of the drugs were more effective than placebos in comparative trials, the researchers concluded that the effect of antidepressants, in general, were ‘mainly modest’
• this challenges the value of the biological approach because it suggests that brain chemistry alone may not account for all cases of, for example, depression

Question 18

evaluation: biological approach is determinist

Answer 18

• sees human behaviour as governed by internal, genetic causes over which we have no control
• however, we have seen that phenotype is heavily influenced by the environment
  > identical twins who share the same genes do not think and look the same
• purely genetic argument becomes problematic when considering crime
  > could a violent criminal be excused from their actions by claiming their behaviour was controlled by a ‘crime gene’?

= this suggests that the biological approach is often too simplistic and ignores the mediating effects of the environment

Question 19

evaluation: natural selection

Answer 19

• critics of darwin’s work, such as karl popper, claim that it is not possible to falsify the theory of natural selection as we cannot show that evolution is happening, we can only deduce it has taken place
• however, others claim that the basic principles are supported by fossil records (eg. showing dinosaurs changing into birds)