Biological Approach Flashcards
(15 cards)
Outline the assumptions of the biological approach
Everything psychological has a biological basis
Our biology is determined by evolution and genes
To investigate the mind, must investigate physical brain
To understand human thoughts and behaviour, must investigate biological structures (physiology) and processes (biochemistry) within brain and body
What is a genotype?
Genetic makeup of individual that is inherited
What is a phenotype?
Observable characteristics of an individual that are expressed as a result of interaction between their genotype and their environment
Outline monozygotic and dizygotic twins
Monozygotic twins are identical and share 100% of DNA
If characteristic purely genetic, concordance rate for MZ twins should be 100%
Dizygotic twins are non identical and share 50% of DNA
If concordance rate significantly higher for MZ twins suggest characteristic mainly genetic
If concordance rate for MZ and DZ similar, suggest characteristic determined by environment
Outline an example of a twin study
Gottesman (1991) reviewed over 40 twin studies and found average concordance rate was 48% for MZ twins and 17% for DZ twins for Schizophrenia
Suggests schizophrenia is partly genetic
Outline natural selection
Give an example of an evolved behaviour
Proposed by Charles Darwin
Natural selection suggest if organism able to adapt to environment, will be more able to survive and reproduce
Adaptive characteristics may occur due to mutation
When organism reproduces these characteristics are genetically transmitted to their offspring and the characteristic will become more common over time
Attachment is adaptive behaviour as infants are helpless and require adult assistance to ensure survival
Creating emotional bond w adult who will care for infant is survival advantage
Outline the brain / the different lobes
Frontal lobe - reasoning, emotions, decision making
Parietal lobe - perception of stimuli and attention
Occipital lobe - visual processing
Temporal lobe - memory and speech
Outline the relationship between biological structures and behaviour
Relationship between biological structures and behaviour shown in ppl w schizophrenia
Enlarged ventricles (fluid filled gaps between brain areas) in central brain areas and the prefrontal cortex of the frontal lobe have been linked to negative symptoms of schizophrenia
Outline the influence of neurochemistry on our behaviour
Neurotransmitters are chemical messengers that travel across synaptic gap during process of synaptic transmission, allowing neurons to communicate
Imbalances in neurotransmitter levels are often associated w atypical behaviour
Eg too little serotonin found in OCD patients, suggesting serotonin has role in preventing the repetition of tasks
Lack of serotonin results in the loss of the mechanism that inhibits task repetition
Evaluate twin studies / genetic explanation using supporting evidence
Strength of genetic explanation is supporting evidence from twin studies
McGruffin twin study on depression and found concordance rate of 46% for MZ twins and 20% for DZ
Suggests at least partly genetic since genetically identical twins over twice as likely to both have the disorder than non identical twins
Evidence supporting role of genes supports idea psychological characteristics are determined by biology
Evaluate the biochemical explanation using practical application
Strength of understanding about biochemical processes in brain is has enabled development of psychoactive drugs that alter levels of biochemicals
Eg knowing depressed ppl have lower levels serotonin, led development of antidepressants that increase serotonin levels and decrease depressive symptoms
Practical applications show how understanding biology can improve lives
Evaluate twin studies using difficulty of separating nature and nurture
Limitation of genetic explanation is research often involves twin studies
Since identical twins usually raised in same environment, impossible disentangle role of inherited and environmental influences
Eg if high concordance rate obtained, cannot be sure whether similarity due to being genetically identical or because are treated similarly
Limitation as such methodological issues affect validity of research into biological factors
Evaluate biological approach / use of brain scans using how it supports psychology as a science
Strength of BA is lab experiments
PET scans used to highlight areas of brain activity (objective and scientific methods)
Because of rigorous control, process meets criteria for psychology as a science as it removes any extraneous variables that may affect results as well as subjectivity inherent in measuring emotions
Creates confidence in research findings of biological explanation
Evaluate biological approach using reductionism
Purely genetic explanations are reductionist
Simplifies cause of human behaviour solely down to genetic transmission
However, inheriting particular characteristic in their genome may only make child vulnerable to develop this in their phenotype
Certain environmental triggers (eg aggressive role models) may be required for behaviour to be expressed
Purely biological explanations may not account for interaction of diff factors
More holistic view needed
Evaluate biological approach using diathesis stress model
Rather than focus on purely biological explanation (nature) to understand human behaviour may be beneficial to use diathesis stress model which explains interaction between nature and nurture
Genes leave individual vulnerable to developing disorder but whether disorder actually develops is influenced by interaction w environmental factor (stressor)
Behaviour not entirely genetic in origin and more beneficial to look at complex interaction between genetic and environment to fully understand
