MAPPING THE MEANINGS OF NOVEL VISUAL SYMBOLS BY YOUTH WITH MODERATE OR SEVERE MENTAL-RETARDATION

The word-learning ability of 12 school-age subjects with moderate or s evere mental retardation was assessed. Subjects had little or no funct ional speech and used the System for Augmenting Language with visual-g raphic symbols for communication. Their ability to fast map novel symb ols revealed whether they possessed the novel name-nameless category ( N3C) lexical operating principle. On first exposure, 7 subjects were a ble to map symbol meanings for novel objects. Follow-up assessments in dicated that mappers retained comprehension of some of the novel words for up to delays of 15 days and generalized their knowledge to produc tion. Ability to fast map reliably was related to symbol achievement s tatus. Implications for understanding vocabulary acquisition by youth with mental retardation were discussed.