Localisation of Function

• What is the Holistic Theory?


  The theory that all parts of the brain are involved in thought processes and action
• Localisation of Function


  The theory that different areas of the brain are responsible for different functions and behaviours
• What are the 4 lobes?

  1. Frontal Lobe
  2. Parietal Lobe
  3. Occipital Lobe
  4. Temporal Lobe
• Frontal Lobe


  Responsible for movement, personality and higher level thinking (problem solving)
• Parietal Lobe


  Responsible for processing information from our senses. Controls memory and their uses
• Temporal Lobe


  Responsible for hearing, speech and memory
• Occipital Lobe


  Responsible for receiving and processing visual information
• Motor Area


  Responsible for controlling movements. Is found in the frontal lobe
• Somatosensory area


  Receives sensory messages such as touch and pain from the rest of the body. Found in the parietal lobe
• Auditory area


  Responsible for analysis of speech related information. Found in the temporal lobe.
• Visual Area


  Processes visual information. Found in the occipital lobe
• What is Aphasia?


  When someone has lost the ability to understand or produce speech
• Paul Broca

  • French physician and surgeon
  • Broca met a patient who had problems with speech and could only say 'Tan'
  • Broca then studied their brain to find damage to the Left Frontal Lobe
• Broca's Area

  • Found in the left hemisphere
  • In the left frontal lobe
  • It is responsible for speech production
• What is Broca's Aphasia?

  An impaired ability to produce language caused by damage to Broca's area
• Karl Wernicke

  • Identified patients that had no problem producing speech but had problems understanding speech
  • He found damage to the left temporal lobe
• Wernicke's Area

  • Found in the left hemisphere
  • In the left temporal lobe
  • Responsible in understanding written and spoken language
• Wernicke's Aphasia


  Impaired ability to comprehend language caused by damage to Wernicke's area
• Brain


  labelled

  
• AO3: Brain Scan Evidence of Localisation

  Researcher used brain scans to demonstrate how Wernicke's area was active during a listening task and Broca's area was active during a reading task suggesting different areas of the brain have different functions
• AO3: Patient HM

  • Suffered a bike accident that gave him epilepsy and had his hippocampus removed which gave him amnesia
  • He could not form new memories but could remember before the surgery
  • This provides evidence for the localisation of function as the hippocampus may play a part in forming new memories
• AO3: Lashley's Research

  • Lashley suggests that higher cognitive functions such as learning are not localised but distributed in a more holistic way
  • Lashley removed areas of the cortex in rats
  • No area was proven to be more important than any other area
  • This suggests that learning is too complex to be localised and requires the whole brain
  • However as rats are used it may not necessarily be applied to humans
• AO3: Plasticity

  • An argument against localisation of function is plasticity
  • This is when the brain has become damaged and a particular function becomes compromised or lost and the brain attempts to reorganise itself in an attempt to recover the lost function
  • This goes against localisation of function that says different parts of the brain have specific functions
• AO3: Generalisability


  Research to support localisation have been extremely rare case studies. This makes the research hard to generalise to the wider population. Individual differences are also apparent between language areas suggesting that function is not universally localised in the same part of the brain for everyone in the same way