Biological Approach

All that is psychological is physiological - since the mind appears to reside in the brain, all thoughts, feelings and behaviours ultimately have a biological cause. Therefore psychology should investigate the brain, nervous system, endocrine system and neurochemistry. Behaviour has a genetic element. So genes should be studied in order to understand human behaviour. 

Twin studies:   Twins reared together - have  a similar environment. If MZ's are  more similar than DZ's it shows the importance of genes twins reared apart - allows genes and environment to be seperated Evaluation:+no other way of studying genes - MZ twins share 100% of their DNA+Share their environment so their is natural control of environmental effects-Most people aren't twins so the results don't necessarily generalise to the whole population-MZ's  may have a more similar environment than DZ's so comparisons can be difficultAdoption Studies:Most direct way to isolate genes and environment. Any similarities between child and biological parent suggests a role for genes. Any similarity between child and adoptive parent suggests the role of environment.Evaluation:+direct comparison of the influence of nature v nurture because they isolate environment from genes.+can investigate a range of variables and use varied samples/methods.-still shared same intrauterine environment which could account for similarities in behaviour-most people aren't adopted so cannot be generalised.

MRI:  shows a picture of the brain inside the skull so that specialists can identify any areas of damage or tumours. a strong magnetic field is sent through the head the magnetic field causes the nuclei in hydrogen molecules in the brain to spin in a particular way, which is picked up by the scanner. PET: allows us to see activity of a working brain a radioactive tracer is injected into the bloodstream the tracer decays when it reaches the brain and gives off positrons. the positrons collide with electrons and form gamma rays that show the amount of energy being used in different areas of the brain.

Practical reasons:+short life span so their whole life can be studied unlike humans and their environment can be tightly controlled.+no demand characteristics+can carry out a procedure that cannot be ethically carried out on humans eg lesioning to study the function of different parts of the brain-difficult to justify the value of research to the public as the benefits of research are difficult to predict.-animals are qualitatively different from humans so results cannot be applied to humansEthical Considerations: minimum numbers of animals should be used to make the experiment as ethical as possible and  no unnecessary practices are carried out take into account the animals social behaviour and dont overcrowd results may not be true in humans , meaning animals have been used in vain some people argue we shouldnt do things to animals we wouldnt do to animals, making all animal studies unethical.

CNS: made up of brain and spinal cord         Nerves in our body send information via the spinal cord to the brain         the brain then processes the information and sends a message to the body through the spinal cord         neurons in the brain pass messages along neurotransmitters.Neurone: Nerve cells that transmit information.              The network of neurons make and the connections between them make up the nervous system              The function of a neuron is to transmit nerve impulses along the length of an individual neuron across the synapse into the next neuron.Synapse: the junction between the end of an axon and the dendrite of another neuron,Hormones: chemicals released into the bloodstream                 homones affect physiological and behavioural funtions                 eg testosterone causes the growth of facial hairBrain lateralisation: the extent to which eah hemisphere is involved in different activities.                            eg language - left & art -right

Key Assumptions

Research Methods

scanning techniques

animal studies

key terms