<P> Spinal nerve C1 is called the suboccipital nerve, which provides motor innervation to muscles at the base of the skull . C2 and C3 form many of the nerves of the neck, providing both sensory and motor control . These include the greater occipital nerve, which provides sensation to the back of the head, the lesser occipital nerve, which provides sensation to the area behind the ears, the greater auricular nerve and the lesser auricular nerve . </P> <P> The phrenic nerve is a nerve essential for our survival which arises from nerve roots C3, C4 and C5 . It supplies the thoracic diaphragm, enabling breathing . If the spinal cord is transected above C3, then spontaneous breathing is not possible . </P> <P> The last four cervical spinal nerves, C5 through C8, and the first thoracic spinal nerve, T1, combine to form the brachial plexus, or plexus brachialis, a tangled array of nerves, splitting, combining and recombining, to form the nerves that subserve the upper - limb and upper back . Although the brachial plexus may appear tangled, it is highly organized and predictable, with little variation between people . See brachial plexus injuries . </P> <P> The anterior divisions of the lumbar nerves, sacral nerves, and coccygeal nerve form the lumbosacral plexus, the first lumbar nerve being frequently joined by a branch from the twelfth thoracic . For descriptive purposes this plexus is usually divided into three parts: </P>

Nerves of the pns carry both sensory and motor information