How many different things can we memorise?

There are some people who can memorise immense amounts and others who forget what they had for breakfast. The difference is down to your genes, we have a million million neurons in our brains and your memory works by making connections between these stronger by a process called long term potentiation. This happens in a part of the brain called the hippocampus and also the amygdala, but we don't know how memory actually works. What we do know for example, is that if you learn lots of languages, particularly from a young age, the part of the brain involved with language (the language cortex) gets bigger.