Two sorts of cells make up the nervous system: neurones and glial cells. Neurones are the building blocks of the nervous system. Information travels along neurones as electrical signals - nerve impulses. These signals are passed to the next neurone in the chain at special sites known as synapses. There are ten times as many glial cells than neurones. Glial cells do not actually conduct electrical impulses, they look after the structure and maintenance of the brain.