localisation of the brain

• what is localisation of the brain?

  • theory stating different brain areas are responsible for different behaviours, processes and activities
• where is the motor cortex?

  • frontal lobe
  • present in both hemispheres
  • left hemisphere controld the right side of the body
• function of the motor cortex

  • generates voluntary motor movements
  • different parts of the cortex controls different body parts
• where is the somatosensory cortex?

  • parietal lobes on the post central gyrus
  • in both hemispheres
• function of the somatosensory cortex?

  • detects sensory information
  • postcentral gyrus dedicated to touch
  • produces sensations of touch, pressure and pain
• where is the visual cortex?

  • in the occipital lobe
  • in both hemispheres
  • different areas process different types of visual information
• where is the auditory cortex?

  • in the temporal lobe
• what is the function of the auditory centre?

  1. auditory pathway begins in the inner ear ,sound waves are converted into nerve impulses
  2. nerve impulses travel via auditory nerve toi cortex
  3. stops at brain stem for basic decoding (duration and intensity)
  4. travels to a relay situation
  5. impulse arrives at the auditory cortex where sound is recognised and gives an appropriate response
• where is Broca's area?

  • posteriori frontal lobe on the left hemisphere
• function of Broca's area

  • controls the mouth, tongue and vocal cords
  • critical for speech production
• localisation of function strengths

  • BRAIN SCAN EVIDENCE: brain scans show Wernick’s area was active when listening + Broca's when reading. TULVING semantic + episodic memories in diff parts of brain 
  • CASE STUDY EVIDENCE: PHINEAS GAGE, pole through most of left frontal lobe. Changed personality to rude + short tempered. Mood regulating brain area affected 
• localisation of function limitations

  • PLASTICITY – brain can adapt + other areas can take over lost function so a more holistic view should be taken e.g. stroke survivors regaining speech 
  • LASHLEY’S RESEARCH – higher functioning isn’t localized but distributed holistically. Removed 10-50% of rat’s cortex learning a maze, found no area was more important. BUT not generalizable to humans  
• discuss what research has shown abouit localisation of the function in the brain

  • language areas are specified into production and undewrstanding
  • broca's patient Tan and Wernick's area
  • Aphasia studies