Neurons (also known as neurones, nerve cells and nerve fibers) are electrically excitable cells in the nervous system that function to process and transmit information. In vertebrate animals, neurons are the core structural components of the brain, spinal cord and peripheral nerves.eurons (also known as neurones, nerve cells and nerve fibers) are electrically excitable cells in the nervous system that function to process and transmit information. In vertebrate animals, neurons are the core structural components of the brain, spinal cord and peripheral nerves.