Rather than a disease, tinnitus is a symptom that may result from various underlying causes and can may be generated at any level of the auditory system and structures beyond that system. The most common causes are hearing damage, noise-induced hearing loss or age-related hearing loss, known as presbycusis. Other causes include ear infections, disease of the heart or blood vessels, Ménière's disease, brain tumors, exposure to certain medications, a previous head injury, earwax, and sometimes, the tinnitus is suddenly perceived during a period of emotional stress. It is more common in those with depression.