Specific learning disability means a disorder in one or more of the basic psychological processes involved in understanding or in using language, spoken or written, that may manifest itself in imperfect ability to listen, think, speak, read, write, spell, or do mathematical calculation, including conditions such as perceptual disabilities, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia. Specific learning disability does not include a learning problem that arises primarily as the result of visual, hearing, or motor disabilities, of an intellectual disability, of emotional disturbance, or of environmental, cultural, or economic disadvantage.