title: The learning of difficult visual discriminations by the moderately and severely retarded.
mesh_terms: D000293:Adolescent; D000328:Adult; D004193:Discrimination Learning; D004495:Education of Persons with Intellectual Disabilities; D006801:Humans; D008607:Intellectual Disability / Q000534:rehabilitation; D008875:Middle Aged; D012050:Rehabilitation, Vocational; D012759:Sheltered Workshops; D013663:Teaching; D014796:Visual Perception