Transparency and recall of symbols among intellectually handicapped adults.

The purpose of this investigation was to examine the transparency and recall of symbols representing three parts of speech (nouns, verbs, descriptors) from three different graphic symbol systems (Blissymbols, Picture Communication System, and Picsyms) among adults with intellectual handicaps. Results suggested that the Picture Communication System (PCS) and Picsyms were more transparent and easier to learn than Blissymbols. Subjects correctly identified significantly fewer Blissymbols representing nouns than either PCS or Picsyms representing nouns. In early stages of recall for nouns, PCS and Picsyms were significantly easier to recall than Blissymbols. Implications of the data for symbol system selection use for persons with severe speech impairments are discussed.