localisation + lateralisation of the brain

• Localisation: the idea that different parts of the brain perform different tasks and are involved with different parts of the body
• Cortical specialisation: looking at specific area of the brain to see which physical and psychological functions they are linked to
• Motor area:

  • voluntary movement in the opposite side of the body
  • control over fine movements
  • back of frontal lobe in both hemispheres
• Somatosensory area:

  • receives sensory input from receptors
  • in the skin including touch, pain, pressure and temperature
  • front of parietal lobe in both hemispheres
• Visual area:

  • receives input directly from the eyes
  • occipital lobe in both hemispheres
• Auditory area:

  • receives input directly from the ears
  • front of temporal lobe in both hemispheres
• Broca’s area:

  • producing language
  • speaking and writing
  • left of frontal lobe
• Wernicke’s area:

  • understanding language
  • top of the left temporal lobe
• Evaluating localisation of function in the brain:

  🙂 Peterson- evidence to support

  🙂 Phineas Gage- evidence to support

  ☹️ Lashley’s rats- evidence against

  ☹️ Brain plasticity
• Hemispheric lateralisation: form of localisation where the two hemispheres of the brain have different specialisations
• The brain had a left and right hemisphere which are connected by the corpus callosum
• Our brain is contralateral, meaning the optic nerve from each eye crosses over into the opposite hemisphere.
• The left hemisphere specialises in language processing.

  The right hemisphere is more dominant in visual motor tasks, recognising faces and analysis via touch.
• Sperry’s split-brain research.

  Procedure:

  1. Describe what you see tasks
  2. Tactile tasks
  3. Draw it tasks
• Sperry’s split brain research conclusions:

  • Any time information is processed by the left hemisphere, participants were able to describe (Language=left hemisphere)
  • Recognising objects is processed by the right hemipshere
  • Visual motor tasks are processed/performed by the right hemisphere
• Evaluating hemispheric lateralisation and split brain research:

  🙂 Evidence to support- Peterson

  ☹️ Contradictory evidence from Danelli

  ☹️ Small sample size

  ☹️ Individual differences - different surgeries