localisation of function

• what is localisation of function?

  different areas of the brain are responsible for different physical and psychological functions
• 🚘 location of motor cortex

  frontal lobe
• function of motor cortex

  controls voluntary movements
• 👃🏼 location of somatosensory cortex

  parietal lobe
• function of somatosensory cortex

  processes sensory information
• 👀 location of visual cortex

  occipital lobe
• function of visual cortex

  receives and processes visual information
• 👂🏼 location of auditory cortex

  temporal lobe
• function of auditory cortex

  processes sound information
• 🗣️ location of broca's area

  left frontal lobe
• function of broca's area

  responsible for speech production
• what happens if broca's area becomes damaged?

  aphasia

  • slow speech
  • lack of fluency
• 💭 location of wernicke's area

  left temporal lobe
• function of wernicke's area

  language comprehension
• what happens if wernicke's area becomes damaged?

  aphasia

  • fluent but meaningless speech
• define hemispheric lateralisation

  certain mental processes are mainly controlled by one hemisphere
• what is the left hemisphere responsible for?

  • language
  • logic
  • analytical tasks
• what is the right hemisphere responsible for?

  • spatial abilities
  • facial recognition
  • perception
• what is the corpus callosum?

  connects the two hemispheres so they can communicate
• ✅ localisation

  strong scientific support

  • Peterson et al - PET scans to establish broca and wernicke's area
  • provides objective evidence
• ✅ localisation

  case studies

  • Phineas Gage - damage to frontal lobe caused personality changes
  • frontal lobe is involved in personality, decision-making and self-control
  • real-life support
• ❌ localisation

  brain plasticity

  • other areas can adapt and take over functions
  • brain is more flexible than suggested
  • brain has holistic nature
• what does split-brain research investigate?

  hemispheric lateralisation
• what's a corpus callosotomy?

  corpus callosum is severed to treat epilepsy
• who researched split-brain?

  sperry
• 📖 sperry's procedure for split-brain research

  • effects of severing corpus callosum
  • 11 epileptic patients undergone split-brain surgery
  • controlled lab experiments using a tachistoscope
  • flashed images or words to left or right visual field
• findings of sperry's split-brain research

  visual task

  • right hemisphere saw the image but couldn't speak
  • left hemisphere verbalised image

  tactile task

  • right hemisphere understands object but couldn't produce speech
  • left hemisphere could name and describe it
• what did gazzanigas find out about split-brain?

  right hemisphere has better facial recognition
• ✅ split-brain research

  empirical evidence for hemisphere

  • left hemisphere dominant for language
  • right hemisphere handles visual-spatial tasks
  • supports modern neuroscience
• ❌ split-brain research

  lacks applicability

  • research was based on 11 patients with epilepsy who underwent a corpus callosotomy
  • unique circumstances
  • lowers external validity
• ❌ split-brain research

  artificial tasks

  • flashing words or images
  • in everyday life, input is processed bilaterally
  • limits real-world relevance
• define brain plasticity

  ability to change and adapt structure and function in response to learning, experience or damage
• what is plasticity triggered by?

  • life experience
  • learning new skills
  • brain damage or trauma
• types of plasticity

  • developmental - changes during growth
  • adaptive - changes following injury
• 📖 key research for plasticity: maguire et al

  • MRI scans of london taxi drivers
  • more grey matter in posterior hippocampus
  • positive correlation with time spent as a taxi driver
• 📖 key research for plasticity: kühn et al

  • played mario for 30 minutes a day over 2 months
  • increased grey matter in hippocampus, prefrontal cortex and cerebellum
• define functional recovery

  undamaged areas of the brain compensate for damaged areas
• what triggers functional recovery?

  • trauma
  • rehabilitation
  • age
• process of functional recovery

  1. neuronal unmasking
  2. axonal sprouting
  3. reformation of blood vessels
  4. recruitment of homologous areas
• 💤 neural unmasking

  • brain contains dormant synapses
  • after damage, these become activated allowing for new neural pathways to form