learning disabilities, in education, any of various disorders involved in understanding or using spoken or written language, including difficulties in listening, thinking, talking, reading, writing, spelling, or arithmetic. They may affect people of average or above-average intelligence. Learning disabilities include conditions referred to as perceptual handicaps, minimal brain dysfunction (MBD), dyslexia, developmental aphasia, and attentional deficit disorder (ADD); they do not include learning problems due to physical handicaps (e.g., impaired sight or hearing, or orthopedic disabilities), mental retardation, emotional disturbance, or cultural or environmental disadvantage. Techniques for remediation are highly individualized, including the simultaneous use of several senses (sight, hearing, touch), slow-paced instruction, and repetitive exercises to help make perceptual distinctions. Students are also assisted in compensating for their disabilities; for example, one with a writing disability may use a tape recorder for taking notes or answering essay questions. Behavior often associated with learning disabilities includes hyperactivity (hyperkinesis), short attention span, and impulsiveness. School programs for learning-disabled students range from a modified or supplemental program in regular classes to placement in a special school, depending upon the severity of the disability. The field of learning disabilities is considered to have emerged as a separate discipline in 1947 with the publication of the book Psychopathology and Education of the Brain-Injured Child by neuropsychiatrist Alfred A. Strauss and Laura E. Lehtinen. The need to help students with these disabilities was first recognized on the federal level in 1958, when Congress appropriated $1 million to train teachers for the mentally retarded. Famous people considered to have had a learning disability include Winston Churchill, Thomas Edison, and Nelson Rockefeller.