A condition that interferes with a student's ability to learn. Even the definition of this term is controversial. The Individuals with Disabilities Education Act amended in 1997 defines a specific learning disability as "a disorder in one or more of the basic psychological processes involved in understanding or in using language, spoken or written, which disorder may manifest itself in imperfect ability to listen, think, read, write, spell, or do mathematical calculations. Such term may include such conditions as perceptual disabilities, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia." Children not included under this provision include those who have learning problems which are "primarily the result of visual, hearing, or motor disabilities, of mental retardation, of emotional disturbance, or of environmental, cultural, or economic disadvantage."