Maguire

• background


  • the hippocampus is an important part of the Bain which is involved in memory and navigation
  • case studies of patients who have experienced damage to the hippocampus revealed difficulties in memory
  • research has also shown that animals which migrate or store food have a larger volume relative to their brain and body size
• aims


  • to investigate the differences in the hippocampi of London taxi drivers compared to controls
  • to further investigate functions of the hippocampus in spatial memory
• sample


  • 16 male London taxi drivers
  • all right handed
  • between 32 and 62 years old
  • licensed for at least 18 months
  • all mentally and physically healthy
  • sample was compared to a control group of 50 scans from an MRI database
• procedure 


  • they compared the taxi drivers' brain scans to 16 scans from the control group (matched for age)
  • data was collected through pixel counting, where number of pixels in scans of the hippocampus and the main body were collected and compared
  • data was also collected through voxel-based morphometry, an objective 3D measure of the volume of grey matter in the brain, calculated from MRI scans by computer
• results


  • significantly increased grey matter volume was found in the taxi drivers' brains compared to the controls' in both sides of the posterior hippocampus
  • but they also showed lower volume in the anterior hippocampus
  • length of time spent as a taxi driver correlated positively with volume in the posterior hippocampus
  • length of time spent as a taxi driver correlated negatively with volume in the anterior hippocampus
• conclusions


  • the study showed regional differences between the hippocampi of London taxi drivers compared to a control group of non-taxi drivers
  • it seems that relying on navigational skills as part of your job is associated with a redistribution of grey matter in the hippocampus