Final answer:
The Supraclavicular Nerves (C3, C4) innervate the skin above the clavicle, supplying sensation to the upper chest and shoulder areas.
Step-by-step explanation:
The Supraclavicular Nerves, which are branches derived from the C3 and C4 cervical spinal nerves, provide cutaneous innervation in the region above the clavicle. Specifically, these nerves supply sensation to the skin of the upper chest and shoulder areas. Sensory signals from the skin and other peripheral sensory surfaces are carried by axons into the central nervous system (CNS). The trapezius muscle, which is innervated by the spinal accessory nerve as well as cervical spinal nerves, is involved in elevating the scapula and clavicle and also receives sensory input from these cervical nerves.