Biological Approach Flashcards
What are the key assumptions of the biological approach
Key words: organisms, genetics, CNS, biochemistry
- views humans as biological organisms
- explains human behaviour in terms of physical factors e.g. genetics (heredity behaviours), the CNS (functioning of the brain), biochemistry (chemicals found in the brain (neurotransmitters) and body (hormones) are believed to influence reactions to the environment (behaviour))
Define genotype and phenotype
Genotype: the genetic make up of an individual which provides a genetic code for how the individual will develop
Phenotype: the observable characteristics of an individual; a consequence of a genotype interacting with the environment e.g. height can be affected by nutrition as well as genes
Why does research into the effect of genes often compare monozygotic twins with dizygotic twins
If a Behaviour has a genetic basis, then it should be more prevalent amongst monozygotic twins as they share 100% of their genes, whereas dizygotic twins only share 50% of their genes
Define concordance rate
The probability that a pair of individuals will both have a certain characteristic e.g. if a a Behaviour has a purely genetic basis, then the concordance rate should be 100% amongst monozygotic twins
Outline the endocrine system
Maintains levels of hormones in the blood and other body fluids, using glands in the body e.g. the pituitary gland
Give an example of research demonstrating the effect of hormones on behaviour
Dabbs study: studied just under 700 male prisoners (by saliva samples) and found that violent offenders had higher testosterone levels than non violent offenders.
What are the two parts of the nervous system and briefly explain what’s included within them
CNS: (master control unit) spinal cord (column of nerves) and brain.
Peripheral nervous system: autonomic nervous system (regulates involuntary body processes e.g. heart rate), sympathetic nervous system (mobilises body resources in response to threat by speeding up heart rate), parasympathetic nervous system (replenishes bodily resources by slowing down other bodily processes) and somatic nervous system (carries sensory info from sensory organs to the CNS and relays commands to muscles; controls voluntary movements)
Define cerebrum and cerebral cortex
Cerebrum: largest part of the brain, split into 2 halves (hemispheres) then the hemispheres are divided into 4 parts (lobes)
Cerebral cortex: the outer surface of the cerebrum is called the cerebral cortex, which is responsible for the higher order functions such as thoughts and language
Define neurons, neurochemistry and neurotransmitters
Neurons: a nerve cell which transmits information in the form of electrical and chemical signals between the nervous system
Neurochemistry: the study of chemical and neural processes within the NS
Neurotransmitters: chemical messengers within the cerebral (brain) fluid, includes excitatory NT (stimulate the brain) and inhibitory NT (balance mood and calm the brain
Give an e.g. of how neurotransmitters may be involved in mental illness
- Depression has been linked to a lack of serotonin in the brain
- Schizophrenia has been linked to an excess of dopamine in the brain
Strengths and weaknesses of the biological approach
Strengths: effective treatments have been developed to help treat mental illness, uses scientific methods of investigation which are precise and objective e.g. brain scanning (MRI and PET)
Weaknesses: has been argued the approach is too reductionist (fails to acknowledge upbringing and culture), relies on the evolutionary theory which ignores what is happening to people ‘now’
