biological approach Flashcards
define the biological approach
approach that suggests behaviour is determined by 4 biological factors; genes, biological structures, neurochemistry and evolution.
how is the biological approach similar to cognitive approach?
want to be scientific
link to cognitive neuroscience!
what are the 3 assumptions of the biological approach?
-every psychological characteristic has a biological root cause
-we must look at biological structures and processes within the body to understand behaviour
-the mind lives in the brain (are the same thing) so all thoughts, feelings and behaviours have a physical basis
what is the genetic basis of behaviour?
behavioural characteristics are inherited the same way as physical characteristics
what is a specific example to support the genetic basis of behaviour?
a mutation in the SERT gene has been linked to OCD
what is an important thing to remember about the role of genes on behaviour?
genes pre-dispose (increase likelihood of developing) us to behaviour, they don’t make certain characteristics INEVITABLE
what is used to study the genetic basis of behaviour and how does this work?
twin studies- concordance rates between twins are calculated
what are concordance rates?
percentage of shared characteristics/ agreement
what is our evidence for genetic basis of behaviour? Give a specific example?
higher concordance rates between Monozygotic twins (share 100% DNA) than Dizygotic twins (share 50% of DNA)
68% of MZ twins have OCD compared with 31% of DZ
what is a limitation of twin studies?
confounding variables- in identical twins there is the CV of nurture, if they look the same they are likely treated the same so higher concordance rates could be due to this not genes.
we have to look at adoption studies to overcome this limitation.
what is genotype?
the genetic make-up (actual genes someone posesses)
what is phenotype?
the expression of genes through physical, psychological and behavioural characteristics
what is phenotype determined by?
the interaction of genes and environmental factors
what does phenotype and genotype demonstrate?
how much of human behaviour is a result of an interaction of nature and nurture
what is an example of twin studies for crimanal behaviour?
Christiansen 1977 studied 3500 pairs of twins in Denmark
looked at concordance rates for criminal behaviour for males and females MZ and DZ- in both genders, MZ higher concordance rates than DZ
the MAOA gene and CDH-13 gene are thought to pre-dispose criminal behaviour (13X more likely with a mutation of these genes)
what is neuroanatomy?
studying how different brain structures affect behaviour
the brain is divided into different areas and structures all responsible for different types of thinking or behaviour
what does research for brain anatomy involve?
using brain scanning technology and studying brain damaged patients
what are 2 examples for neuroanatomy?
- language; governed by two areas; Broca’s (speech production) and Wernicke’s area (speech comprehension)
- OCD; abnormal functioning if the frontal lobes (linked to emotional regulation and decision making) may be linked to hoarding disorder as causes deficits in decision making
how does the case of Phineas Gage support neuroanatomy?
the brain structures which were damaged are the sections which caused change in his behaviour
after accident he became irritable and lacked social inhibition- he had damage to the left pre-frontal cortex responsible for emotion regulation and decision making!
what is neurochemistry?
how chemicals in the brain influence behaviour
what are brain chemicals called and how can these link to mental disorders?
neurotransmitters
abnormal functioning of these may include too much, too little or poor re-absorption in the synapses
how can neurotransmitters be linked to behaviour and development of psychological disorders (examples)?
too little serotonin linked too depression
too much dopamine linked to schizophrenia
what is evolution?
change in characteristics that are inherited over several generations
what is natural selection?
the process by which any biological characteristic which gives an individual an adaptive advantage are successfully passed on through reproduction over generations.
what is an adaptive advantage?
something that increases chances of survival or gives advantage over competition to reproduce
how has memory has been evolved?
some individuals randomly have better memory than others
gives these an adaptive advantage as they can remember where food is and which berries are poisonous
those with better memory more likely to survive and reproduce, passing on the better memory to next generation
over generations the species gets a better memory as those with poorer memory cannot survive and reproduce.
explain how phobias have evolved?
some people are quicker at identifying spiders and running away
gives these people an adaptive advantage over those who don’t have this characteristic
only those scared of spiders will survive and reproduce
pass on the scared of spider genes so phobia evolves
what are 2 strengths of the biological approach?
-scientific
-real life application
what are 4 limitations of the biological approach?
-deterministic
-reductionist
-cause and effect
-confounding variables involved
how is the biological approach scientific?
uses precise scientific methods e.g. scanning techniques, twin studies and drug trials
this increases the internal validity of the findings
means biological approach is a credible approach and useful for explaining behaviour
how real-life application a strength of the biological approach?
understanding neurochemistry has led to treatment for those suffering e.g. SSRIs increasing serotonin levels for depression
OR
twin studies Denmark 1977
approach therefore is useful and credible as applied to real life
how is the biological approach deterministic?
states we have no control over behaviour because behaviour is all determined by genetic makeup, individuals cannot be held responsible for actions.
means approach not well liked because humans like to think they have some sort of free-will
approach won’t be perceived as useful for explaining behavuiour.
how is the biological approach reductionist?
all human behaviour explained through biological processes
oversimplifies behaviours
e.g. Phinneas Cage neuroanatomy- behaviour change might have been just due to PTSD not due to damage to specific area of brain
incomplete explanation for behaviour
why is cause and effect a limitation of the biological approach?
we can’t assume brain abnormality is the direct cause of mental illness as abnormality may have development after the illness
e.g. low serotonin might not directly cause depression, the development of depression may result in low serotonin
how are confounding variables a limitation for the biological approach?
confounding variables- in identical twins there is the CV of nurture, if they look the same they are likely treated the same so higher concordance rates could be due to this not genes.
we have to look at adoption studies to overcome this limitation.
