Neurons are masters of communication, transferring messages throughout your body – even when you’re not thinking about it. The standard blueprint of a neuron includes the cell body (also called the soma), which contains the nucleus; dendrites, which are extensions that receive signals from other neurons; and an axon, that branches off to relay the signal further on to another neuron or muscle cell. In mammals, the dendrites are often wrapped in an insulating material known as a myelin sheath, which helps the signal travel extra fast by jumping from node to node between the insulating Schwann cells.

A single neuron can be connected to as many as 100 000 others, and these interactions are constantly changing. Brains are constantly undergoing changes to their neuron connections: new ones are formed and unused pathways die and are pruned out. This process is part of how we can learn new things and store information in a brain. When a fetus is developing, 250 000 neurons are formed every second, adding up to over a trillion cells!