From Sue Chinn
Both Andy Coghlan in “Thank culture for your modern mind” (17 May, p 9) and Susan Greenfield in “Reinventing us” (17 May, p 48) refer to a study of London taxi drivers that showed them to possess a partially enlarged hippocampus. Unless this was a before-and-after study, is it not more plausible that only those endowed with enlargement in the area which stores spatial navigation are able to memorise the street map of London?
The editor writes:
• Eleanor Maguire and colleagues at University College London found that “the longer a driver has been working, the bigger their rear hippocampus” (New Scientist, 18 March 2000, p 11). In 2003 they tested the hypothesis Sue Chinn proposes on people who were not taxi drivers and found no association between hippocampal volume and navigational expertise (Hippocampus, vol 13, p 250).
London, UK
