Investigate brain structure

• At first was trickier to investigate brain structure and function
• Before brain scanning psychologists relied on case-studies for people who experienced brain injury or had brain operations.
• Phineas cage:

  • Damage to frontal lobe after explosion at work in an iron bar
  • After accident he was less organised and more impulsive with personality changes including increased aggression
  • Led to belief area of brain is responsible for these behaviours
  • Only one person so it isn't representative of whole population
• Use of Animals

  • Animals used to study brain structure and behaviour but differences between animals and humans means results may not be useful
  • Use animals because it may not be ethical for humans
• Brain scans examine brain activity:

  PET scans

  CAT scans

  MRI scans

  fMRI scans
• PET scan = show which parts of the brain are active during different tasks
• CAT scans = detect damaged parts of the brain, tumours and blood clots
• MRI scans = detect small tumours and provide detailed information about structure
• fMRI scans = provide structural and functional information
• Maguire et al - A study of taxi driver's brains - method

  • Natural experiment MRI scans from 16 licensed male London taxi drivers were compared with a control group who had never driven taxis
  • All Ps good in general, neurological and psychiatric health with average age of 44
  • All drivers working for at least 18months
• Maguire et al - A study of taxi driver's brains - Findings

  • Average right posterior hippocampus was significantly larger for taxi drivers than control group
  • Increased size relative to length of time been a taxi driver
  • Longer been working, longer right posterior hippocampus
• Maguire et al - A study of taxi driver's brains - Conclusion

  • Hippocampus responsible for storing a spatial representation of the environment
  • Specific navigational demand on taxi drivers resulted in physical change
• Maguire et al - A study of taxi driver's brains - Evaluation

  • Findings of study help those with brain injuries to show size of structures in brain influenced by cognitive activity
  • Rehabilitation tailored for specific needs of individuals
  • Good level of control --> Reliable
  • Sample size small --> only generalise to male taxi drivers in London