Disability

Broadly construed, a disability is an impairment in physical, mental, intellectual, and/or sensory functioning. Disabilities are usually classified as severe, profound, moderate, or mild, depending on the individual’s need for support, which may be lifelong. Specific types of disabilities are diverse and often multifaceted, including intellectual; physical (e.g., hearing, vision, paralysis, epilepsy, muscular dystrophy, cerebral palsy, missing extremities); speech, language, and learning; and psychiatric (e.g., anxiety disorders, schizophrenia, anorexia). A disability can manifest at any time within a person’s life (although developmental disabilities typically manifest before the ages 18–22 years), and it can be visible or invisible, long-term, episodic, or temporary and thus vary in the degree to which it imposes limitations and resists effective treatment. The causes of disabilities are also extensive and may be attributable to genetic abnormalities, congenital infections, perinatal or postnatal trauma, environmental poisons or deprivation, malnutrition, abuse, accidents, lack of parental or child health care, or they may be of unknown origin. This entry provides an historical view of the diagnosis and treatment of disabilities, significant advancements from a global perspective, and progress and future directions for research and practice.

Historically, the perception, attitude, and treatment of individuals with disabilities have been determined by societal norms and/or cultural beliefs. At various points in time and within various cultures, individuals with a disability were considered inferior, possessed by supernatural or evil spirits, the symbol of a curse on an entire family, or [Page 629]the reincarnation of a god. Consequently, treatment of individuals with disabilities ranged from extermination, forced sterilization, institutionalization, neglect, or maltreatment to being treated with acceptance, kindness, and even reverence. On the whole, individuals with disabilities have been seen as incompetent and incapable of decision-making or self-determination. From the 1800s to the mid-1900s, in Western countries, the vast majority of people with disabilities were segregated and hidden in institutions, asylums, hospitals, and attics with only their most basic needs (e.g., food, shelter, and clothing) being met. Services that were provided were based on a medical model of disability (treatment and care based on a medical diagnosis of bodily function or structure such as spinal injury, blindness, etc.), without regard for the environmental and psychological needs of the individual. Most negative attitudes and treatments were based on misconceptions and lack of an informed understanding of specific disabilities and the differing functional capacities of disabled persons.

With advances in medical technologies and diagnostic instruments, changes began to take place in the diagnosis and treatment of persons with disabilities; however, only recently have significant advances been made for the provision of support and resources to enable disabled persons to live to their full potential.