localisation of function Flashcards
what is localisation of function?
the idea that certain functions are localised to certain areas in the brain
motor area
- frontal lobe
- responsible for voluntary movements by sending signals to muscles
- damage can cause issues with movement
somatosensory area
- parietal lobe
- receives incoming sensory info from the skin to produce sensations
- damage can cause feelings things that aren’t there or not feeling things
visual area
- occipital lobe
- receives and processes visual info
- info from the right visual field is processed in the left hemisphere and vice versa
- damage causes issues in seeing and processing things
auditory area
- temporal lobe
- analyses and processes acoustic info
- info from the left ear primarily goes to the right hemisphere and vice versa
- damage causes issues with hearing
broca’s area
- left frontal lobe
- speech production
- damage causes broca’s aphasia - slow and inarticulate speech
wernicke’s area
- left temporal lobe
- language processing and comprehension
- damage causes wernicke’s aphasia - producing fluent but meaningless sentences
give a strength of localisation of function
1/1
there are multiple case studies that support broca’s and wernicke’s areas. broca’s area for example was named after a patient called tan, who could understand spoken language but couldn’t produce coherent words. in a post mortem examination broca found damage to tan’s left frontal lobe, creating broca’s area. furthermore, wernicke found that people with damage to this area were able to speak but not comprehend language. these studies and research support the existence of these regions, therefore increasing the validity of the localisation of function theory.
give a limitation of localisation of function
1/4
theory is criticised. the equipotentiality theory for example suggests that basic motor and sensory functions are localised, but higher and more complex mental processes aren’t. it was suggested that intact areas could take over the functions of different areas following a brain injury. this casts doubt on the localisation of function theory, suggesting not all functions are localised to a specific brain area
give a limitation of localisation of function
2/4
there is however an issue with generalising the results of case studies to the wider population, due to its limited sample of just one person. without further research conducted it cannot be concluded with certainty that these functions are universally localised to these regions. additionally, a further MRI on tan’s brain did find lesions in broca’s area, but also found evidence to suggest other areas may have contributed to the issues with speech production. this suggests there may be other regions of the brain associated with speech production, which limits the validity of the localisation of function theory
give a limitation of localisation of function
3/4
some psychologists suggest it’s more important to study how brain areas communicate with each other rather than specific areas on their own. a case study for example followed a man who couldn’t read after damage to the connection between his visual cortex and wernicke’s area. this highlights that damage to the connection between two different regions can result in impairments that resemble damage to the area associated with the function, which reduces the theory’s credibility. also, by reducing complex human behaviour to a single brain region, the theory can be seen as biologically reductionist, and so a deeper understanding of the brain is required to better understand mental processes.
give a limitation of localisation of function
4/4
the idea of localisation of function doesn’t account for the impact of individual differences. a psychologist found that women tend to have proportionately larger broca’s and wernicke’s areas, which would explain the greater communication ease amongst women. this however highlights a level of beta bias in the theory by ignoring the differences between men and women
