Tinea Versicolor is a surface yeast infection that causes changes in the outer most layers of the skin. It is caused by a yeast-like fungus normally found on our skin in small numbers. When overgrowth occurs, a rash appears as scaly white to tan spots over the upper arms, chest, back and neck. After sun exposure, these spots are more noticeable because they do not tan. With this type of tinea infection, it is important to remember that the infection will be cured in a week, however, the loss of color can last for months.