Deafblindness is the condition of little or no useful hearing and little or no useful sight. Different degrees of vision loss and auditory loss occur within each individual. Because of this inherent diversity, each deafblind individual's needs regarding lifestyle, communication, education, and work need to be addressed based on their degree of dual-modality deprivation, to improve their ability to live independently. In 1994, an estimated 35,000–40,000 United States residents were medically deafblind. Helen Keller was a well-known example of a deafblind individual. To further her lifelong mission to help the deafblind community to expand its horizons and gain opportunities, the Helen Keller National Center for Deaf-Blind Youths and Adults (also called the Helen Keller National Center or HKNC), with a residential training program in Sands Point, New York, was established in 1967 by an act of Congress. The deafblind community has its own culture, comparable to those of the deaf community and the blind community. Members of the deafblind community have diverse backgrounds but are united by similar experiences and a shared, homogeneous understanding of what it means to be deafblind. Some deafblind individuals view their condition as a part of their identity. Epidemiology The medical condition of deafblindness occurs in different forms. For some, this condition might happen congenitally from birth as a result of genetic defect, for others it happens suddenly due to a form of illness or accident that results in a modality deprivation of either vision or hearing, or both. A person might be born deaf and become blind at a later stage in life, or vice versa. In any given case of deafblindness, many possible onsets and causes of this condition exist; some happen gradually, others happen unexpectedly and suddenly. The diagnosis of deafblindness could be medically classified into specific types based on one's symptoms and causes. The two overarching types of deafblindness are congenital and acquired. Congenital deafblindness: the condition of deafblindness from birth Pregnancy complexities Effects of alcohol/drugs Fetal alcohol syndrome A result of prematurity Causes from illness/infection Rubella AIDS Cytomegalovirus Congenital syphilis Toxoplasmosis Genetic conditions (evident from birth) Anomalies/syndromes (numerous genetic defects may contribute to one's medical condition of deafblindness, of which some of more well-known syndromes are listed) CHARGE syndrome Cochleosaccular degeneration with progressive cataracts Down syndrome Marshall syndrome Congenital rubella syndrome Stickler syndrome Trisomy 13 Acquired deafblindness: condition of deafblindness developed later in life Genetic conditions (evident at a later