It is one of the most extensive systems in the body, with nerves extending throughout that communicate with the brain. The nervous system takes sensory information that we gather from the world around us and delivers it to the brain . This information is then processed by the brain, which generates an output signal that is transmitted to the correct part of the body. The signal from the brain drives a response, making our bodies either move, or adjust to the environment. Each nerve is supplied with tiny blood vessels for nourishment.
Some nerves carry information in one direction only, while others are two-way.
One-way nerves are described as sensory nerves when they carry information to the brain, or motor nerves, when they carry signals from the brain. Both of these types of nerves are found throughout the body. The two-way nerves are called mixed nerves and they are mostly found in the spinal cord. Nerve cells have to be able to respond to stimulation and to carry signals through the body. Once a nerve has been activated, it carries an electrical signal along its length.