Brain localisation and Hemispheric Lateralisation

• The brain consists of 4 main regions:

  • Occipital lobe - visual information
  • Temporal lobe - auditory information
  • Parietal lobe
  • frontal lobe
• Parietal Lobe - integrates information from the different senses and plays an important role in spatial navigation
• Frontal Lobe - associated with higher order of functions, including: planning and logic
• Localisation of Function - certain brain functions have certain locations within the brain eg. language, memory
• Motor Cortex - located in the frontal lobe and is responsible for voluntary movements by sending signals to the muscles in the body
• Somatosensory Cortex - Located in the parietal lobe, it processes sensory information from the skin
• Visual Cortex - located in the occipital lobe and receives visual information
• Auditory Cortex - located in the temporal lobe, it's responsible for processing acoustic information
• Broca's Area - named after Paul Broca, it is located in the left frontal lobe and processes speech production.
• Wernicke's Cortex - named after Carl Wernicke, it is located in the left temporal lobe and is responsible for language comprehension.
• Broca's Aphasia - damage to Broca's area leading to speech with small sentences being produced with great effort and often forgetting small words
• Wernicke's Aphasia - damage to Wernicke's area leading to impaired comprehension and production of speech, speaking in jumbled sentences that others can't understand
• Hemispheric Lateralisation - the idea that the brain is split into two halves, each with a different function with functional specialisation, eg. left for language, right for visual motor task
• Corpus Callosum - connects both hemispheres through nerve fibres and allows for interhemispheric communication
• Left Hemisphere:

  • Language dominant
  • Controls the right hand
  • Receives information from the Right Visual Field (RVF)
• Right Hemisphere:

  • Visual motor task dominant
  • Controls the left hand
  • Receives information from the Left Visual Field (LVF)
• Commissurotomy - Split brain patients who have had their corpus callosum cut typically to avoid epileptic seizures
• Brain Plasticity - refers to the brain's ability to change and adapt because of experience
• Synaptic Pruning - as we age, rarely used connections are deleted and frequently use connections are strengthened
• Functional Recovery - is the transfer of functions from a damaged area of the brain after trauma to other undamaged areas
• Neural Plasticity - healthy brain areas take over functions of areas damaged, destroyed or even missing (eg. Jodie Miller)
• Spontaneous recovery - The brain's natural ability to quickly regain some function after trauma, before the effects of rehabilitation
• Neural Unmasking - where 'dominant' synapses open connections to compensate for a nearby damaged area of the brain
• Brain Localisation:

  A) Parietal Lobe

  B) Frontal Lobe

  C) Temporal Lobe

  D) Occipital Lobe

  E) Motor Cortex

  F) Somatosensory Cortex

  G) Visual Cortex

  H) Auditory Cortex

  I) Broca's Area

  J) Wernicke's Area