A Brain in a Glass Bowl

What this book is about

In a laboratory dish, a few hundred thousand human brain cells were kept alive, wired to a screen, and taught to play Pong. They learned. Nobody had told them what a game was, what a paddle was, or what winning meant — and still, within minutes, the ball started coming back.

This book begins there and works backwards. What is a neuron, really? How does one cell decide to fire? What does it mean for a signal to travel, for a connection to strengthen, for a group of cells to *learn* something without anyone teaching it? By the end you have a working picture of how a brain — any brain, including the one reading this — turns electricity into behaviour.

The audience on the cover is a class-7 or class-8 reader. The real audience is anyone who has never been given a physical feel for what a thought is made of. Every abstract idea in here is reduced to something you can hold: a switch, a queue, a rope pulled tight, a path worn into grass by feet.

What is inside

• Neurons, synapses and the electrical logic of a single cell
• How a dish of cells was taught to play, and why that is not the same as understanding
• Memory as a physical change, not a stored file
• The honest limits — what this experiment does not prove
• Activities, a glossary, a quiz and the sources, as in every volume