localisation of function

• what is localisation of function?

  specific functions are localised in specific areas of the brain
• how does localisation relate to brain damage?

  when brain damage occurs, associated function is also damaged
• what are the 4 lobes of the brain?

  Frontal, parietal, temporal, occipital
• where is the motor area found?

  back of frontal lobe in both hemispheres
• what is the function of the motor area?

  controls voluntary movement in opposite sides of the body
• how does damage to motor area affect us?

  causes loss of fine movement
• where is the somatosensory area?

  front of parietal lobe in both hemispheres
• what is the function of the somatosensory area?

  Sensory perception
• where is the visual area?

  in the left occipital lobe
• what is the function of the visual area?

  • left hemisphere= sends info from right-visual field of both eyes
  • right hemisphere= sends info from left-visual field of both eyes
• how does damage to visual area affect it's function?

  can produce partial blindness in both eyes
• where is the auditory area?

  in the temporal lobe of both hemispheres
• what is the function of the auditory area?


  analyses speech-based functions
• how does damage to the auditory area affect it's function?

  damage produces partial hearing loss, more extensive damage the more extensive loss
• where is Broca's area?

  left frontal lobe
• what is the function of Broca's area?

  Speech production
• how does damage to Broca's area affect it's function?

  causes Broca's aphasia
• what is Broca's aphasia?

  slow, laborious speech
• where is Wernicke's area?

  left temporal lobe
• what is the function of Wernicke's area?

  language understanding
• how does damage affect the function of Wernicke's area?

  causes Wernicke's aphasia
• what is Wernicke's aphasia?

  difficulty understanding language and production of nonsense words
• how does the case study of Phineas Gage relate to localisation?

  • emphasises how brain functions are localised
  • had brain damage to frontal lobe, became unpredictable and had personality changes
  • alerted fact that frontal lobe involved in personality
• what are strengths for localisation theory?

  • has neurosurgery evidence
  • has brain scanning evidence
  • case study evidence
• what are limitations for the localisation theory?

  • neurosurgery evidence for holism
  • questions on localisation of language centres
• what neurosurgery evidence is there for the localisation theory? (AO3)

  • a cingulotomy isolates cingulate gyrus as treatment for OCD
  • Dougherty et al studied 44 people who underwent a cingulotomy
  • at follow up, 30% had success, 14% partial success
  • highlights despite low results, behaviours for disorders are localised
• what evidence counters that of Dougherty's? (AO3)

  • Lashley removed different areas of cortex in rats
  • during their learning of maze route
  • no matter area of brain removed, still able to learn route
  • suggests learning is holistic as uses all areas of brain not specific ones
• what brain scanning evidence is there for localisation theory? (AO3)

  • Petersen et al used brain scans to demonstrate activity in language centres
  • Broca's active during reading activity, whereas, Wernicke's active during listening activity
  • confirms everyday behaviours are localised
  • provides scientific, empirical evidence of localisation
• why is the questioning of language centres a limitation for localisation theory (AO3)

  • Dick + Tremblay found only 2% of researchers agree that language centres localised to left hemisphere
  • fMRI scans have been helpful in studying brain more clearly
  • so from meta-analysis' have found language distributed across cortex, holistically
  • suggests language not confined to left hemisphere