Biological Approach (APPROACHES 2/6) Flashcards
key assumptions
how think, feel and behaviour in terms of physical factors within body e.g. hormones, genetics, evolution, NS
nervous system (brain structure and neurochemistry)
genetics
brain main focus - mind as result of biological structures and processes
behaviour due to biology, can be modified using drugs
experimental evidence on animals inform about humans - share biological similarities
genetics
behaviour, personality, mental illness and intelligence due to inherited characteristics
half of genes from mother, half from father
some characteristics from one gene, some from combinations
genes control physical processes
dominant vs recessive genes
two of every gene (apart from X and Y chromosomes)
dominant = shows even if one copy
recessive = both genes must be recessive to show
genotype
actual set of genes an individual has
genetic material given by sperm and egg
phenotype
observable behavioural and physical characteristics of individual as consequence of genetics and environment
twin studies
method of investigating whether psychological characteristics have genetic basis
looking at concordance rates (likelihood if one has trait, the other will too)
monozygotic twins
identical
share 100% of DNA
would expect 100% concordance rates if behaviour or characteristic is genetic
dizygotic twins
non-identical
share 50% of DNA - like regular siblings
would expect 50% concordance rates if behaviour or characteristic is genetic
twin study example
Gottesman and Shields
compared MZ and DZ twins for schizophrenia
concordance rates much higher for MZ twins but not 100%, suggesting there are also environmental elements
adoption studies
twins often share same environment and genes
isolate influence of genes and environment
similarities with biological parent = genetic influence
similarities with adoptive parent = environmental influence
adoption study example
Heston
nature / nurture in schizophrenia
support genetic cause but environmental factors should not be ignored
nervous system
nervous system
peripheral central
autonomic somatic brain spinal cord
sympathetic, parasympathetic
CNS
all reactions pass through
simple, reflex actions go through spinal cord before brain processes
somatic nervous system
controls muscle movement, relays info from eyes, ears and skin to CNS
autonomic nervous system
controls involuntary bodily functions and regulates glands
sympathetic nervous system
fight or flight response
activity increases when stressed, in danger or physically active
parasympathetic nervous system
relaxes body after stress or danger
helps run life-sustaining processes e.g. digestion during safety and relaxation
frontal lobe
consciousness and communication
memory and attention
motor control
problem solving
parietal lobe
sensory perception
occipital lobe
visual processing
temporal lobe
auditory processing
study of the brain
scans to examine patterns of brain activity and anatomical structure
PET scans
radioactive chemical showing parts of brain are active when thinking about different things
CAT scans
detected damaged structures of the brain by taking images
MRI scans
brain structure
fMRI scans
brain function / activity
neurochemistry
action of chemicals in the brain
thoughts and behaviours rely on transmission of messages
neurotransmitters
chemical messengers that travel between neurones via synapses
excitatory NTs trigger nerve impulses in post-synaptic neurone and stimulate brain
inhibitory NTs limit nerve impulses in post-synaptic neurone and have calming effect on brain
evolution
changes in inherited characteristics in a biological population over successive generations
gradual development of different kinds of living organisms from earlier forms during the history of the earth
Charles Darwin emphasises that evolution happens by natural and sexual selection –> the process in which organisms better adapted to their environment are healthier, live longer and reproduce more frequently, passing on the genes that made them reproductively fit onto their offspring
natural selection
animals with particular traits that provide them with an advantage are more likely to survive and reproduce, thereby passing on their adaptive traits to their offspring
sexual selection
acts on ability to obtain or successfully copulate with a male
makes organisms go to extreme lengths for sex ;)
e.g. peacocks maintain elaborate tails
biological approach strengths
scientific and objective methods
use brain scanning techniques e.g. PET, CT and MRI scans used to measure brain function or structure
objective measure and data, not open to interpretation
more likely to be valid and reliable data
real life applications
useful to society
knowledge of brain structures and function has enable treatment to be developed to assist people
lead to greater understanding of brain abnormality and associated behaviour
enable people to live a more normal life
highly applicable
biological approach weaknesses
reductionist
only focuses on biological constructs linked to behaviour
explains behaviour through genetics / hormones
ignores environmental influences e.g. social factors and upbringing
would explain depression through inherited genes and fault neurotransmitters rather than environmental factors such as lack of support or friends
too simplistic to suggest behaviour only influence by biology
lacks validity
cause and effect
assumes behaviour is result of biological causes
treatments development may be limited
e.g. focus on drugs for depression
treatment may not be fully effective, not based on singular cause
limited applicability
nature / nurture
sees biology as only cause to behaviour and ignores environmental influence - only nature
ignores nurture or combination
difficult to separate effects
decreases validity
deterministic
assumes that genes or brain structures determine how we behave
takes away element of free will to behaviour
social responsibility