Maguire was inspired by previous research that had been done, specifically by Blakemore and Cooper about functional brain plasticity, however, she wanted to expand on this and research structural brain plasticity.
She wanted to investigate the hippocampus, which is a major part of the limbic system in charge of navigation.
Previous research had suggested that the hippocampi of some animals grows in size during times when their navigational and special reasoning skills are exercised more often.
However, there had been no research illustrating whether human brains would plasticise as a result of environmental changes, therefore, Maguire wanted to investigate this further and the best people to use were London Taxi Driver as they had to learn 'The Knowledge' of London and had much navigational experience.