SOLIDIFICATION PERIOD (C.1975 TO 1985)
The period from about 1975 to 1985 was a period of relative stability as the field moved toward consensus on the definition of learning disabilities as well as methods of identifying students with learning disabilities. It was a period of considerable applied research, much of it funded by the USOE, that resulted in empirically validated educational procedures for students with learning disabilities. There was some upheaval with respect to professional organizations, but this unrest was relatively brief.
Solidification of the Definition
In 1975, Congress passed Public Law 94-142, the Education for All Handicapped Children Act. With this law, learning disabilities finally achieved official status as a category eligible for funding for direct services.
U.S. Office of Education 1977 definition. By the early 1970s, the NACHC definition of 1968 had become the most popular one among state departments of education (Mercer, Forgnone, & Wolking, 1976). This no doubt figured into the USOE’s virtual adoption of the NACHC definition for use in the implementation of P.L. 94-142:
The term “specific learning disability” means a disorder in one or more of the psychological processes involved in understanding or in using language, spoken or written, which may manifest itself in an imperfect ability to listen, speak, read, write, spell, or to do mathematical calculations. The term includes such conditions as perceptual handicaps, brain injury, minimal brain dysfunction, dyslexia and developmental aphasia. The term does not include children who have learning disabilities which are primarily the result of visual, hearing, or motor handicaps, or mental retardation, or emotional disturbance, or of environmental, cultural, or economic disadvantage. (USOE, 1977, p. 65083)
The 1977 USOE definition, with minor wording changes, has survived until today as the definition used by the federal government. However, that does not mean that other definitions have not been promulgated by parent and professional groups. Examples of two developed during this period were those of the National Joint Committee on Learning Disabilities (NJCLD) and the ACLD.
NJCLD definition. In 1978, the major learning disabilities professional organizations as well as the ACLD formed the NJCLD in order to attempt to provide a united front in addressing issues pertaining to learning disabilities. In 1981, the NJCLD developed the following definition:
Learning disabilities is a generic term that refers to a heterogeneous group of disorders manifested by significant difficulties in the acquisition and use of listening, speaking, reading, writing, reasoning or mathematical abilities. These disorders are intrinsic to the individual and presumed to be due to central nervous system dysfunction. Even though a learning disability may occur concomitantly with other handicapping conditions (e.g., sensory impairment, mental retardation, social and emotional disturbance) or environmental influences (e.g., cultural differences, insufficient-inappropriate instruction, psychogenic factors), it is not the direct result of those conditions or influences. (Hammill, Leigh, McNutt, & Larsen, 1981, p. 336)
In formulating this definition, the NJCLD was purposeful in its exclusion of any mention of psychological processes, which were integral to the USOE definition. By not mentioning psychological processes, the NJCLD distanced itself from perceptual and perceptual-motor training programs, which had lost favor in the research community.
Federal Regulations for Identification of Learning Disabilities
When P.L. 94-142 was implemented in 1977, in addition to the inclusion of a definition of learning disabilities, the federal government issued regulations pertaining to the identification of students with