AO1 - localisation of function

• Holistic theory


  Replaced by localisation in recent years
• Scientists supported the holistic theory


  Early 19th century
• Holistic theory


  All parts of the brain were involved in processing thought and action
• Localisation theory


  Specific areas of the brain were linked with specific physical and psychological functions
• Brain area damaged


  Function associated with it was also affected
• Brain


  • Divided into two hemispheres
  • Lateralised
• Left hemisphere


  Controls right side of the body
• Right hemisphere


  Controls left side of the body
• Cerebral cortex


  • Outer layer of the brain
  • Like a 'tea cozy' covering the inner part of the brain
  • About 3mm thick
  • Appears grey due to the location of cell bodies - known as grey matter
• Lobes of the cerebral cortex

  • Frontal
  • Parietal
  • Occipital
  • Temporal
• Motor area


  • Back of the frontal lobe on both hemispheres
  • Controls voluntary movement
  • Damage may result in loss of control over fine motor movements
• Somatosensory area


  • Front of both parietal lobes
  • Processes sensory information from the skin e.g touch, heat, pressure etc
  • Amount of somatosensory area devoted to a particular body part denotes its sensitivity
• Visual cortex


  • In the occipital lobe at the back of the brain
  • Each eye sends information from the right visual field to the left visual cortex and from the left visual field to right visual context
  • Damage to left hemisphere could cause blindness to the in the RVF of both eyes
• Auditory cortex


  • In the temporal lobe
  • Analyses speech-based information
  • Damage may produce partial hearing loss – the more extensive the damage the more serious the loss
• Broca's area


  • In left frontal lobe
  • Speech production
  • Identified by Broca in 1880s
• Wernicke's area


  • In front temporal lobe
  • Language comprehension
  • Identified by Wernicke in 1880s
• Bocas aphasia  

  • Characterised by speech that is slow, laborious and lacking in fluency  
  • Patients may have difficulty finding words and naming objects  
• Wernicke’s aphasia

  • Patients produce language but have problems understanding it, so they produce fluent but misleading speech.  
  • Patients will often produce nonsense words (neologisms)