National Institute on Deafness and Other Communication Disorders, National Institutes of Health, U.S. Department of Health & Human Services. “Presbycusis is the loss of hearing that gradually occurs in most individuals as they grow older. Hearing loss is a common disorder associated with aging. About 30-35 percent of adults between the ages of 65 and 75 years have a hearing loss. It is estimated that 40-50 percent of people 75 and older have a hearing loss.” This site explains the causes, symptoms, and what can be done about presbycusis. Includes communication tips for communicating with an elderly person with hearing loss.