How the Body Works : The Anatomy of Learning

When we learn something, new pathways are established in the brain's nerve network. Between the fine branches of adjacent nerve cells are synapses, which transmit information. In an enlargement there are at first few such junctions between the dendritic spines, but during learning new spines grow, enabling new synapses to develop so that there are now firmly established routes for the transfer of certain information. The brain's activity has altered subtly. Arrows indicate the one-way flow of information at a synapse.