One of the nerves that originates in the spinal cord.
There are 31 pairs of spinal nerves. They consist of the 8 cervical nerves, 12 thoracic nerves, 5 lumbar nerves, 5 sacral nerves, and 1 coccygeal nerve.
- Nerve, tenth cranial
The tenth cranial nerve, and one of the most important, is the vagus nerve. All twelve of the cranial nerves, the vagus nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral column. The vagus nerve originates in the medulla oblongata, a part of […]
- Nerve, third cranial
The upper eyelid muscle which raises the eyelid; The extraocular muscle which moves the eye inward; and The pupillary muscle which constricts the pupil. Paralysis of the oculomotor nerve results in drooping eyelid (ptosis), deviation of the eyeball outward (and therefore double vision) and a dilated (wide-open) pupil.
- Nerve, trigeminal
This nerve functions both as the chief nerve of sensation for the face and as the motor nerve controlling the muscles of mastication (chewing). Problems with the sensory part of the trigeminal nerve result in pain or loss of sensation in the face. Problems with the motor root of the trigeminal nerve result in deviation […]
- Nerve, trochlear
The trochlear nerve controls the superior oblique muscle of the eye, one of the extraocular muscles, the muscles that move the eye. Paralysis of the trochlear nerve results in rotation of the eyeball upward and outward (and, therefore, double vision). The trochlear nerve is the fourth cranial nerve. (The twelve cranial nerves emerge from or […]
- Nerve, vagus
A remarkable nerve that supplies nerve fibers to the pharynx (throat), larynx (voice box), trachea (windpipe), lungs, heart, esophagus, and the intestinal tract as far as the transverse portion of the colon. The vagus nerve also brings sensory information back to the brain from the ear, tongue, pharynx, and larynx. The vagus nerve is the […]