Psychedelics Open Your Brain. You Might Not Like What Falls In.

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If you’ve ever been to London, you know that navigating its wobbly grid, riddled with curves and dead-end streets, requires impressive spatial memory. Driving around London is so demanding, in fact, that in 2006 researchers found that it was linked with changes in the brains of the city’s cab drivers: Compared with Londoners who drove fixed routes, cabbies had a larger volume of gray matter in the hippocampus, a brain region crucial to forming spatial memory. The longer the cab driver’s tenure, the greater the effect.

The study is a particularly evocative demonstration of neuroplasticity: the human brain’s innate ability to change in response to environmental input (in this case, the spatially demanding task of driving a cab all