Localisation of brain function

• What theory of the brain was widely adopted by psychologists before the 19th century?

  Holistic theory of the brain
• What is now widely assumed about brain damage and associated functions?

  If brain damage occurs to a specific area, the associated function would also be damaged
• What does the localisation of function theory state?

  • Different areas of the brain are responsible for different behaviours, processes, or activities.
  • The brain is divided into left and right hemispheres.
  • Some functions are dominated by one hemisphere (lateralisation).
  • Activity on the left side of the body is controlled by the right hemisphere and vice versa.
• What is the outer layer of both hemispheres called?

  Cerebral cortex
• How does the human cerebral cortex differ from that of other animals?

  The human cortex is more developed
• What are the four lobes of the brain?

  1. Frontal lobe
  2. Parietal lobe
  3. Occipital lobe
  4. Temporal lobe

  
• What are the four specific areas of the brain that should be known?

  1. Motor cortex
  2. Somatosensory cortex
  3. Visual cortex
  4. Auditory cortex

  
• What are the two language centres of the brain?

  1. Broca’s area
  2. Wernicke’s area

  
• What is the function of the motor cortex?

  It sends signals to muscles to control motor functions
• What does the somatosensory cortex do?

  It receives signals from the sense of touch
• What is the primary function of the visual cortex?

  It decodes visual sensory input
• What condition may result from damage to visual areas?

  Cortical blindness
• Where is the primary auditory cortex located?

  In the temporal lobes on either side
• What happens if the motor cortex is damaged?

  Loss of control over fine movements
• What is the role of the somatosensory cortex?

  It is responsible for sensory information from the skin
• What does damage to the occipital lobe cause?

  Cortical blindness
• What is the function of the auditory area?

  It analyses speech-based information
• What is Broca’s area responsible for?

  Speech production
• What happens if Broca’s area is damaged?

  It causes Broca’s aphasia
• What is Wernicke’s area responsible for?

  Language comprehension
• What happens if Wernicke’s area is damaged?

  It causes Wernicke’s aphasia
• What is a strength of localisation theory based on brain scans?

  • Petersen et al (1988) showed Wernicke's area active during listening tasks.
  • Broca's area was active during reading tasks.
  • Suggests different functions for these areas.
• What did Tulving et al (1994) reveal about memory?

  • Semantic and episodic memories are located in different parts of the prefrontal cortex.
• What did Lashley propose about cognitive functions?

  • Higher cognitive functions are not localised.
  • They are distributed holistically across various locations in the brain.
• How does neural plasticity challenge localisation theory?

  • The brain can reorganise itself to recover function of damaged areas.
  • Documented cases of stroke victims recovering abilities suggest non-localisation.
• What did Dick & Tremblay (2016) find regarding language areas?

  • Very few researchers believe language is only in Broca’s and Wernicke’s areas.
  • Advanced fMRI techniques identified regions in the right hemisphere and thalamus.

  
• What are the strengths and weaknesses of localisation theory?

  Strengths:

  • Evidence supports localisation of functions.
  • Case studies like Phineas Gage support localisation.

  
  

  Weaknesses:

  • Lashley’s findings suggest cognitive processes are distributed.
  • Neural plasticity shows recovery of functions in different brain areas.