General somatic afferent fibers

The general somatic afferent fibers (GSA, or somatic sensory fibers), afferent fibers, arise from cells in the spinal ganglia and are found in all the spinal nerves, except occasionally the first cervical, and conduct impulses of pain, touch and temperature from the surface of the body through the posterior roots to the spinal cord and impulses of muscle sense, tendon sense and joint sense from the deeper structures.

Examples of nerves containing GSA fibers include the trigeminal nerve, the facial nerve, the glossopharyngeal nerve, and the vagus nerve.