A chronic form of eczema, seborrheic dermatitis appears on the body where there are a lot of oil-producing (sebaceous) glands like the upper back, nose and scalp.
Cells that make melanin and are found in the lower part of the epidermis. Melanin is the pigment that gives skin its natural color. When skin is exposed to the sun or artificial light, melanocytes make more pigment and cause the skin to darken.