Symbolic understanding of pictures and words in low -functioning children with autism and normally developing 18- and 24-month old toddlers
Many children with autism with limited language abilities utilize a pictorial system of communication for expressive language such as the Picture Exchange Communication System (PECS), in which words are paired with pictures and pictures are exchanged for desired items in the world. This research investigates whether low functioning children with autism, including users and non-users of a PECS type system, learn picture, word and object relations as associative pairs or whether they understand the referential, symbolic, relations between pictures and words, on one hand, and objects, on the other. This research also examines when, during the course of normal development, children understand pictures and words as symbolic. In Experiment 1, children were taught a new word (“whisk”) through the labeling of a picture of a whisk. After repeated pairings of the word and picture, participants were shown the picture and a real, previously unseen, whisk and asked to indicate the whisk. Normally developing 18- and 24-month-old children always included the real object in their choice, and never selected the picture alone. Control measures established that a simple novelty preference or real item bias could not account for the results. Children with autism, in contrast, associated the word with the picture rather than to the object. Children with autism with prior PECS experience were even more likely to indicate the picture alone. Experiment 2 established that children with prior PECS experience are not simply biased to select any picture in the test trial. A third study confirmed that perseverative responding to the last reinforced response could not account for the results of Experiment 1 obtained from children with autism. Taken together, these results confirm that the mapping between words and pictures for low-functioning children with autism, particularly users of a pictorial communication system, is an associative relation, rather than a referential one, which contrasts with results obtained with normally developing toddlers as young as 18-months of age.
0633: Cognitive therapy
0620: Developmental psychology