It’s a picture of a fish, a salmon actually. In an MRi scanner. Emitting a perfectly valid signal. It looks meaningful. It’s not. It’s a dead salmon. And that’s the thing – when it comes to neuroscience and its relevance to you, how do you tell the difference between useful, and a dead Salmon?

Well, its not easy, if what interests you is human behaviour, and this is why. Below is a diagram for understanding how the brain can operate at different levels at the same time. Just like a huge building is a function of bricks, our behaviour is a function of interactions at the neuro molecular level.