Experiment included: 16 righthanded male London taxi drivers and 50 righthanded males who di do not drive taxis
It was also a singleblind study that is, the researcher did not know whether she was looking at the scan of a taxi driver or a control
The study is correlational in nature as the IV is not manipulated by the researcher. The researchers were looking to see if there was a relationship between the number of years o of driving a taxi and the anatomy of one's brain.
pixel counting revealed that the posterior hippocampi of taxi drivers were significantly larger relative to those of control subjects and the anterior hippocampi were significantly smaller
the posterior hippocampus is involved when previously learned spatial information is used, whereas the anterior hippocampal region may be more involved during the encoding of new environmental layouts.
Some might argue that those with larger hippocampi might be more spatially talented and thus chose to be taxi drivers; this does not explain the correlation between the size of the hippocampus and the number of years driving.