But as your book explains, our brains are quite plastic…
In 2000, a landmark study demonstrated how the brains of London black-cab drivers changed as they took the Knowledge. The hippocampus, which is involved in navigation, learning and memory, enlarged in cabbies who passed the test. This study got a lot of attention and informed the idea that we can hone our brains in the same way as muscle and therefore change our ingrained habits, even become superhumans if we just train our brains in the right way. But now there’s a lot of information coming out of the genomics revolution, particularly studying how neural circuits are laid down under the direction of DNA in babies at just 20 weeks’ gestation and we’re seeing a lot of behaviours are ingrained or coded from very early on. For example, anxiety, obesity, depression and addictive behaviour have all been revealed to have a quite high hereditary basis. But of course, all these behaviours may be amplified and reinforced by the decisions of our parents.