Categories of Deafblindness

Adapted from Supporting Young Adults who are Deaf-Blind in Their Communities (1995), Everson, J., Paul H. Brookes Publishing Co., (Maryland)

There are four widely accepted categories of deafblindness:  
1.  Congenital deafblindness,
2.  Adventitious or Acquired deafblindness,
3.  Congenital deafness-adventitious/acquired blindness, and
4.  Congenital blindness-adventitious/acquired deafness (Taff-Watson, 1984).  

Congenital Deafblindness

Individuals labelled congenitally deafblind are those who are born with dual visual and hearing impairments or who experience dual sensory losses early in the developmental period.  Congenital rubella syndrome (CRS) is one of the most prevalent etiologies associated with congenital deafblindness.  Other frequent etiologies include prematurity, pre- and perinatal trauma, CHARGE association, and other less common syndromes.  There are at least 80 syndromes associated with both visual and auditory losses.  

Acquired Deafblindness

Individuals labelled adventitiously deafblind are those who experience dual sensory losses later in life, postlingually.  The vision and hearing losses may be simultaneous and/or acute, or they may occur at separate times and/or be progressive.  There are many causes of adventitious deafblindness, including diseases causing high fevers and/or accumulated toxins in the body, such as  kidney failure, diabetes, meningitis, encephalitis, and reactions to medications (Wynne, 1987).  In addition, trauma, particularly brain injuries resulting from automobile and/or motorcycle accidents, are a disturbing and increasingly more common cause of adventitious sensory losses.  Individuals who are adventitiously deafblind are educated and typically have employment histories as “hearing-sighted individuals”.  Wynne (1987) notes that “the word ‘traumatic’ is too mild to describe the (adventitious) dual sensory loss of hearing and vision.  It is more than a sensory loss; the person’s self-image is shattered.  This person now has two choices:  survive with a shattered self-image or reconstruct a new self image” (p. 14).  These individuals, who are educated in a “hearing-sighted world”, use speech as an expressive form of communication.  However they lack receptive communication skills and need to learn new tactual systems rapidly.  Psychological, social, vocational,        living, and recreation aspirations will require rebuilding and new skills will need to be learned.

Congenital Deafness - Adventitious / Acquired Blindness

Individuals who are labelled congenitally deaf-adventitiously blind are those who are born hearing impaired or deaf and experience a severe vision loss or blindness later in life.  The most common etiology, and in fact, the lead ing cause of all deafblindness, is Usher Syndrome (National  Retinitis Pigmentosa Foundation, Inc., 1991).   There are at least two specific types of Usher syndrome - Usher type I and type II, and probably at least two more (Kimberling et al., 1989).  About a dozen other syndromes exist with combinations or congenital hearing loss, retinitis pigmentosa (RP), and other medical conditions such as obesity, extra fingers, and mental retardation (Kimberling et al., 1989).  Each is characterized by moderate to profound prelingual hearing loss with the late childhood or early adulthood onset of RP.  The visual field loss resulting from RP is progressive.  Degrees of vision and hearing loss, and the age of onset vary considerably      among individuals and types of Usher syndrome.  In fact many individuals are unaware of their visual loss until their late teens, 20s or even 30s.

A young adult with Usher syndrome is typically educated in a residential school for people who are deaf or in classrooms for students who are deaf or have hearing impairments.  American Sign Language (ASL) is typically the student’s primary language, and ties with the deaf community and immersion in deaf culture may be very strong.  Usher syndrome and other adventitious visual losses are especially challenging to individuals with hearing impairments and deafness because of the strong visual foundation of ASL.  Young adults with congenital deafness and adventitious visual losses who are ASL users will typically need to make a gradual transition to tactual signing and other tactual, non-visual communication methods (Wynne, 1987).  

Congenital Blindness - Adventitious / Acquired Deafness

Congenital blindness and adventitious deafness are terms that describe those individuals who are born with visual impairments or blindness and who experience a hearing loss later in life.  These individuals have relied on speech as an expressive and receptive communication mode, and they are generally proficient in braille and have received O&M instruction.