The biological approach Flashcards
(19 cards)
What does the biological approach propose?
All behaviour has a biological origin - to understand human behaviour fully, it is necessary to understand internal biological structures and processes e.g. genes, nervous system, neurochemistry and evolution
How do genes influence behaviour?
Genes carry information in the form of DNA which carries instructions for characteristics
Genotype - genetic makeup - fixed from birth
Phenotype - expression of genes, observable characteristics of a person (influenced by both genetic inheritance and interaction of this with the environment)
What does heredity mean?
Passing of characteristics from one generation to the next through genes - reason why offspring ‘take after’ their parents
What is the genotype?
Genetic code that is ‘written’ in the DNA of an individuals cells
What is the phenotype?
The physical appearance that results from inherited information
Why can we not determine the genotype simply from just observing the phenotype?
Someone may inherit a recessive gene for something else but this will not be expressed if they have also inherited a dominant gene for something else e.g. may have a recessive gene for blue eyes but a dominant gene for brown
What does the term heritability mean?
The amount of variability in a trait within a population that can be attributed to genetic differences between individuals within the population- the more a trait it influenced by genetic factors, the greater its heritability e.g. studies of identical twins have suggested that that variation in individual intelligence (what makes one person smarter than another) could be 60-80% due to genes
What is the influence of biological structures on behaviour?
Neurons and the nervous system
The brain - cerebrum makes up 85% of the total mass of the brain - outer surface of the cerebrum is the cerebral cortex which is responsible for ‘higher-order’ functions such as thought and language
The cerebrum is divided into two halves (hemispheres) further divided in 4 lobes: frontal, temporal, parietal and occipital
What is the frontal lobe involved with?
Functions such as speech and thought
What is the parietal lobes involved with?
Processing sensory information such as touch pain and temperature
What is the temporal lobe involved with?
Hearing and memory
What is the occipital lobe involved with?
Processing visual information
What is the influence of neurochemistry on behaviour?
Neurotransmitters: travel from one neuron to the next across a synapse - excitatory neurons trigger nerve impulses in the receiving neuron and stimulate the brain into action e.g. dopamine and inhibitory neurotransmitters that inhibit nerve impulses to calm the Brian and balance mood e.g. serotonin
Hormones: chemicals produced by endocrine glands - in response to signal from the brain, hormones are secreted directly into the bloodstream and travel to ‘target cells’ and exert their influence by stimulating receptors on the surface/inside cells - causes a physiological reaction in cell altering activity
How has evolution and natural selection (according to Charles Darwin) influenced behaviour?
Behaviours that lead to survival are those that are passed on - the most successful individuals are the ones more likely to survive and reproduce
Successive generations will develop behaviours that are even more likely to lead to survival and reproductive success
What is a strength of the biological approach?
Real-world applications - development of drug therapies - greater understanding of brain and certain behaviours
What is a limitation of the biological approach?
Often based on correlational results despite causation being strongly implied
e.g. one explanation for schizophrenia suggests that a lack of activity in the mental striatum is linked to negative symptoms such as abolition - research only tells us there is an association but it cannot tell us whether reduced activity in that area causes the behaviour or if the behaviour causes lower activity in that part of the brain
Why is the biological approach overly reductionist?
We cannot fully understand a behaviour without also taking account of the other factors that influence it e.g. cognitive, emotional and cultural factors, all of which had a significant influence on behaviour
Why is the biological approach overly deterministic?
Ignores factors such as free will and environment
Potentially overemphasis the role of nature in behaviour (cannot be falsified - lacks scientific validation)
What are the dangers of genetic explanations?
Can lead to genetic screening of the population to identify genetic susceptibility to certain things e.g. criminal behaviour
Also may create danger as genes might be used as a convenient explanation for some behaviours despite the fact that the connection between genes and complex behaviour such as criminality is far from straightforward
HOWEVER, this can be helpful in intervening early, helping individuals to avoid environmental situations that might trigger this predisposition
