Localisation

Cards (17)

  • Localisation of function of the brain
    Specific functions belong to specific areas of brain
  • Pre-19th century theory
    • Holistic theory; all parts of brain involved in thought and action
    • Suggests if a part broken, nothing function at all
  • Post-19th theory
    • Localisation theory; Broca & Wernicke, specific parts for specific roles
    • Damaged part would only affect damaged function
  • Brain hemispheres
    • Left hemisphere controls right body
    • Right hemisphere controls left body
  • Lateralisation
    One hemisphere dominates functions
  • Grey matter
    Cerebral cortex – outer layer of brain, grey colour
  • Broca's area
    • Frontal lobe, left hemisphere, related to speech production
    • Lesions in right hemisphere do not have speech deficit
    • 1861 – patient couldn't say anything but 'Tan'
    • Lesion found in left hemisphere
  • Wernicke's area
    • Temporal lobe, comprehension of language
    • Overlaps into motor regions and sensory regions – vocals and process stimuli for meaning
    • Both Broca's and Wernicke's areas work together to create coherent conversation
  • Frontal lobe
    • Motor cortex – voluntary movement [send signal to muscles of body]
    • Damage = struggle with coordination and movement control
  • Parietal lobe
    • Somatosensory cortex – represents sensory info from skin receptors
    • The amount on a body part denotes sensitivity e.g. face and hands
  • Occipital lobe
    Visual cortex – processes visual info
  • AO1
    • Localisation vs holistic – post 19th vs pre-19th
    • Hemispheres & cerebral cortex – lateralisation and cerebral cortex, 'grey matter'
    • Motor, somatosensory, visual and auditory centres – frontal, parietal, occipital and temporal lobes
    • Language area of brain – Broca and Wernicke's areas
  • AO3 strength - brain scan

    • Petersen 1988 – Wernicke active listening, Broca active reading; Tulving 1994 –semantic and episodic in PFC
    • Broca for speech production, Wernicke for lang comprehension
    • brain scan as objective measurement of activity, support localisation - sound scientific evidence therefore high validity
  • AO3 strength - neurosurgical evidence


    • Dougherty 2002 – OCD patients successful response to cingulotomy [lesion of cingulate gyrus] post-32 weeks
    • modern procedure reduces compulsive acts due to removing areas influencing it
    • localised symptoms and behaviours associated w/ serious mental disorders
  • AO3 limitation - holistic animal studies


    • Lashley 1950 – rats with a partially removed cortex learn a maze
    • holistic distribution of higher cognitive functions – learning required every part of cortex
    • learning is too complex to be localised and requires involvement of whole brain
  • AO3 counter to limitation

    caution needed for drawing conclusions from animal studies and applying to humans – human cortex more developed than animals; therefore, low generalisability
  • label centres of the brain
    .
    A) Broca's
    B) motor
    C) visual
    D) frontal
    E) parietal
    F) Wernicke's
    G) occipital
    H) somatosensory
    I) auditory