The regulations for Public Law 101-476, the Individuals with Disabilities Education Act (IDEA), define a learning disability as a "disorder in one or more of the basic psychological processes involved in understanding or in using spoken or written language, which may manifest itself in an imperfect ability to listen, think, speak, read, write, spell or to do mathematical calculations."

The Federal definition further states that learning disabilities include "such conditions as perceptual disabilities, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia." The label "learning disabilities" describes a syndrome, not a specific child with specific problems. The definition assists in classifying children, not teaching them. Children with learning disabilities may exhibit a combination of characteristics.

Many different estimates of the number of children with learning disabilities have appeared in the literature (ranging from 1% to 30% of the general population). The U.S. Department of Education (2000) reported that, in the 1998-99 school year, over 2.8 million children with learning disabilities received special education and related services.

Students who have learning disabilities may exhibit a wide range of traits, including problems with reading comprehension, spoken language, writing or reasoning ability. Hyperactivity, inattention and perceptual coordination problems may also be associated with learning disabilities. Other traits that may be present include a variety of symptoms, such as uneven and unpredictable test performance, perceptual impairments, motor disorders, and behaviors such as impulsiveness, low tolerance for frustration, and problems in handling day-to-day social interactions and situations.

Examples, Subsets and Synonyms for Learning Disorders (learning disabilities, Specific Learning Disorders)

• Reading Disorder (Dyslexia)
• Arithmetic Disorder (Dyscalculia)
• Writing Disorder (Dysgraphia, Graphomotor Disorder)
• Disorder of Written Expression
• Language Disorder