Biological Flashcards
Assumptions of the biological approach:
- everything psychological is initially biological
- focus on how biological processes and structures effect behaviour
- most of human behaviour has a physiological cause which may be altered by environmental factors
- the mind lives in the brain (mind and brain are one entity)
What are nuerochemicals???
Chemicals in the Brian that regulate psychological and physiological functions
Methods to investigate genetic basis of curtain behaviour:
Twin studies, family studies, adoption studies, selective breeding
Twin studies:
This is in order to investigate the genetic basis of behaviour
Monozygotic (MZ) - one zygote (one egg that has been fertilised and splits into 2 embryos)
Dizygotic (DZ) - two zygotes (2 separate eggs that where fertilised by different gametes)
Concordance rates: the extent to which a pair of twins is similar in trades or characteristics
Despite having the same genotypes they have subtlety different phenotypes (e.g fingerprints)
‘-> this is due to the environment
Family studies:
1869 - Francis Galton “all natural abilities are inherited”
Resemblance between family members is the result of genes and the environment
E.g alcoholism - is shown to be an inherited predisposition
Adoption studies:
Involve comparing a trait or characteristic between adopted children and their biological or adoptive parents
Selective breeding:
• This method involves artificially selecting male and female animals for a particular trait.
• These animals are then put together in order to breed and produce offspring.
• Selective breeding is used to demonstrate how behavioural characteristics may be genetic . e.g. ‘maze bright’ rats
Many factors are measured in genetic-behavioural studies such as…..
Intelligence, aggression, other habits, addictions, mannerism
Phenotype vs genotype
Genotype is what the genes are coding for (genetic programming)
Phenotype is the expressed characteristic
**phenotypes effected by environmental factors unlike genotype **
Recessive vs dominant
A recessive gene only shows if the individual has 2 copies of the gene
A dominant gene is always expressed if present even if there is only one
Heterozygous vs homozygous
Heterozygous - the genotype consists of 2 different allele
Homozygous - the genotype consists of 2 of the same allele
What is evolution?
The changes in inherited characteristics in a biological population over successive generations
There are 2 main concepts in evolutionary theory, they are…..
Natural selection
Sexual selection
Natural selection
Animals that have a mutation that is advantageous are more likely to live and reproduce and pass adaptive traits onto their offspring
3 principles determine whether the animal in the environment is able to apart:
- the principle of diversity (the variety within species)
- the principle of interaction (how this variety of species adapt and fit in with the environment)
- the principle of differential amplification (those who adapt and survive reproduce - will not die out)
Sexual selection
- males have an abundance of sperm which allows them to reproduce with many females
- however woman are limited and as such are likely to be more particular about who the father of their offspring is
Research methods for biological approach:
- lab experiments
- brain scans
Brain scan types :
- PET (Positron emission tomography - shows which patterns of the brain are active during a task)
- CAT (detects damaged parts of the brain, tumours and blood clots)
- MRI (Detect small tumours and provide detailed information about structure)
- fMRI (Structural and functional information)
- **SQUID Magnetometry ** (accurate images of the brain activity measuring the magnetic fields generated when neurones are activated )
Strengths of the biological approach:
- it is a scientific approach (Highly scientific methods e.g scans)
- establishes psychology as a respectable science
- leads to treatment and intervention to those suffering (e.g anti- depressants)
- measurements are objective (all produced by machines )
Limitations of the biological approach:
deterministic - believe that we are determined by our physiology (no free will)
reductionist - stating that all human. Behaviour can be explained via biological processes is unrealistic (not unique as individuals)
ignores the role of the environment
focus is generally on rare conditions that don’t effect most people
Measurements are subject to human error
correlation>causation
Lacks ecological validity
