//Biological approach Flashcards
What are genes
- segments of DNA modelcules that code physical and psychological features
- make up chromosomes
What are neurones
-a nerve cell which transfers information throughout the nervous system
What is evolution
-the change in the characteristics of a species over several generations and relies on the process of natural selection
Key assumptions
- human behaviour can be explained by lookig at biology e.g. hormes, genetics, nervous system
- if we explain all behaviour using biological causes, unwanted behaviour could be modified or removed using biological treatments e.g. medication for menal illness
- experiemental research conducted on animals can inform us about human behaviour and biological influences because we share lots of biological similarities
How can genetics be used to explain behaviour
- at conception, and egg and sperm join to make 46 chromsomes
- each chromosome is made up of a coil of DNA which is made up of genes
- genes contain the information that make us unique in appearance
- genes are important in the development of the brain and have a role in behaviour
- genotype- genes that a person has
- phenotype- characteristics that their genes produce e.g. eye coloyr
What is Darwin’s evolution theory
- individuals that are better adapted to their environment through having better genes are more likely to survive to reproduce
- eventually less useful genes will be eliminated
- process of natural selection- early humans become better adapted to their environments
How do genes explain psychological traits
- faulty genes are known to cause some diseases that have psychological effects e.g. Huntington’s disease
- biological psychologusts reckon that genetics can explain psychological traist e.g. gender, behaviour, personality, intelligence
- psychologists also study genetics to see which genes make some people more likely to develop mental illnesses or addictions
- twin studies and adoption studies are useful for investigating these areas
Twin studies and schizophrenia can be used to look at the role of genetics- why
- identical twins share 100% of their genes
- non identical only share 50%
- therefore if schizophrenia has a purely genetic basis and if one twin suffers from schizophrenia then the other twin will too
Gottesman (1991)- meta analysis of twin studies- method, results, conclusion
- meta anlysis of 40 twin studies
- having an identical tiwn with schizophrenia gave you a 48% chance of developing the condition- 17% chance in non identical twins
- therefore schizophrenia has a strong genetic basis
Gottesman (1991)- meta analysis of twin studies- conclusion
- meta analysis carried out on field study- high ecological validity
- because identical twins share 100% of their genes, it might be expected that both twins would always suffer from the same conditions
- because the twins had developed schizophrenia in only half the cases means that another factor must also be involved
- identical twins tend to be treated more similarly than non identical twins so family environment may play a role
Biological psychologists believed that behaviour can be determined by brain structure. Why was this a problem
- before brain scanning techniques were devloped, psychologists relied on case studies of people who had experienced a brain injury or had brain operations
- if the person had brain damage in a specific area and a change in behaviour, the assumption could be made that the two were related
- non human animals have been used BUT differences between human and animal brains and may not be useful when applied to human behaviour
Phineas Gage 1848- used to show how brain structure and function and related
- Phineas Gage 1948- damage to frontal lobe after bar went through head
- after accident he was less organised, more impulsive and personality changed e.g. increased aggression
- led to idea that brain is responsible for these behaviours
- however this is a case study of one person so not representative of population
- no controlled circumstances- less scientific
What are brain scans and what are the 5 techniques
examine patterns of brain activity and antomy
- PET scans- show which parts of brain are active during different tasks
- CAT scans- detect damaged parts of the brain, tumours and blood clots. Brain structure shown
- MRI scans- detect small tumours and provide detailed information about structure
- functional MRI scans- provide structural and functional information
- SQUID magnetometry- provide accurate images of brain activity by measuring magnetic fields generated when neurons are activated
How can the nature-nurture debate be used
The genotype describes the genetic configuration of an individual, whereas phenotype describes the combined effects of genetic makeup and surrounding environment on behaviour. The nature-nurture debate highlights a key argument in psychology, over the relative influence of biology and environment on the characteristics of an individual; an extreme biological approach assumes that these are determined solely by nature
How has brain structure been investigated in psychology
- aggression
- memory-HM unable to use long term memory- hippocampus important role
- psychopathology
