Two varieties of secondary retardation.
D002648:Child; D002657:Child Development; D003072:Cognition Disorders; D004192:Discrimination, Psychological; D004495:Education of Persons with Intellectual Disabilities; D006801:Humans; D008607:Intellectual Disability / Q000145:classification / Q000175:diagnosis*; D008606:Mental Processes; D011203:Poverty; D012924:Social Conditions; D013663:Teaching; D013850:Thinking