Unlike other organs, the brain has evolved to adapt to the environment. This unique ability is driven by communication between many billions of neurons.
Neurons are cells in the brain that are specialized for communication. Unlike other organs, the brain has evolved to adapt to the environment, to change constantly in response to changes in the world around us, to learn. This unique ability is driven by communication between many billions of neurons, which send signals by way of tiny electrical charges known as action potentials. Neurons come in many different shapes and sizes and can range in size from fractions of a millimeter to over a meter long. Ultimately, however, most neurons conform to a standard blueprint, which consists of a soma (cell body), dendrites, axon, and axon terminal (where synapses are formed). Each of these structures performs a specific and important purpose. You can find links to these structures in the Related Items section. Neurons are connected by a multitude of networks, which allow them to communicate in hugely complex ways. Communication is coordinated by chemical signals that travel across synapses – the junctions where neurons connect. Neurotransmitters play an important role in transferring and modifying the signals, which can be excitatory or inhibitory. If a receiving (postsynaptic) neuron is sufficiently excited, it will produce an action potential (thereby communicating with a subsequent neuron). Neurons can also communicate directly by forming electrical synapses with one another.