You remember your way home. Some birds and animals store food for later use and memorize their locations. In both cases, the type of memory involved is referred to as spatial memory. This is particularly associated with the brain area called the hippocampus.

Taxi drivers in London, England remember their way around and use spatial memory to a very high degree daily. In a study, researchers compared the hippocampi of taxi drivers with driving experience of 1.5 to 42 years to that of the men who had no extensive navigational experience.

There is no difference in the overall volumes of the hippocampus between the two groups.

However, the posterior region of the hippocampi of the taxi drivers has a significantly greater volume and a greater amount of gray matter.

Also, the increase is correlated with driving experience – the longer the working history, the more gray matter.

Researchers suggest that the increase in the regional volume of the hippocampi in these drivers is acquired through their navigating experience, and that the “mental map” the drivers have of London is stored (or processed) here.