Studied by 3 people
Assumptions of the Biological Approach.
Everything psychological is at first biological.
Much of human behaviour has a physiological cause which may be genetically or environmentally altered.
Genes affect behaviour and influence individual psychological differences between people.
What does the Biological Approach investigate?
The approach investigates how biological structures and processes within the body impact on behaviour.
What is the definition of Evolution?
= the changes in inherited characteristics in a biological population over successive generations.
Evolution & Genetic basis for behaviour : (3 terms)
Natural Selection.
Sexual Selection.
Selective Breeding.
Natural selection.
Biological approach explains there is a genetic basis to natural selection as advantageous genes which increase someone’s chance of survival are passed onto future generations.
Sexual selection.
Women make their choice of who to mate with.
We have limited eggs, men have unlimited sperm.
Women raise the infants, men usually have a lesser role.
Selective breeding.
Artificially selecting male and female animals for a desirable trait.
Explain the terms Genotype & Phenotype?
Genotype : The particular set of genes that a person possesses.
Phenotype : The way genes are expressed through physical, behavioural and psychological characteristics.
Phenotype = genes + environment.
How do Recessive and Dominant genes show in offspring?
Recessive genes only show if the individual has 2 copies of the gene.
Dominant genes only need one to show.
What are the genetic differences of identical and non-identical twins and why?
Identical twins : Monozygotic, one fertilised egg is split, forming two separate embryos, share 100% genes.
Non-identical twins : Dizygotic, two separate eggs are both fertilised by different sperm, share 50% genes, SAME as the amount for siblings.
What are concordance rates and how does it apply to identical / non-identical twins?
= The extent to which both twins share the same characteristic.
There should be a 100% concordance rate between MZ twins if a particular characteristic / trait is genetic.
DZ twins will show lower concordance rates - as will siblings.
Evaluating the biological approach : strengths.
Scientific methods of evaluation, makes use of a range of precise and highly scientific methods in order to investigate the genetic and biological basis of behaviour. Eg scanning techniques and family studies. These advances in technology mean that it is possible to accurately measure biological and neural processes in ways that are not open to bias.
Real-life application, increased understanding of biochemical process in the brain has led tot he development of psychoactive drugs, treating mental illnesses such as depression. Fluoxetine offering an alternative to cognitive behaviour therapy - also cheaper and less time consuming. This matters because it means that sufferers are able to manage their condition and live a normal life.
Evaluating the biological approach : Weaknesses.
Cannot separate Nature and Nurture, fails to acknowledge the influence of environment when studying twins, siblings and families. The biological approach argues any similarities in the way they behave or look must be genetic. In recent studies, DZ twins often show hight concordance rates than siblings even though they both share 50% of genes. This means that the findings could be as easily be interpreted in support of nurture rather than nature and suggests the approach is limited.
Determinist view of behaviour, the approach is biologically determinist in the sense that it sees all behaviour is governed by internal, biological causes over which we have no control. It suggests that all behaviour is a result of genetics, heredity, hormones and the firing neurone. This matters because it suggests oversimplification of the complex process involved in cognition and behaviour.
