Final answer:
A dermatome is an area in the skin that sends sensory information to the spinal cord via a nerve. Different spinal nerves innervate specific regions of the skin, creating topographic regions known as dermatomes.
Step-by-step explanation:
An area in the skin that sends sensory information to the spinal cord via a nerve is called a dermatome. Dermatomes are topographic regions on the skin that relate to the location of sensory endings based on the spinal nerve that contains those fibers.
For example, the fibers of the eighth cervical nerve innervate the medial surface of the forearm and extend out to the fingers.