Picto-ideographic message encoding in cerebral-palsy: the participation of verbal processes

Abstract

The paper is part of a research project devoted to the investigation of cognitive processes involved in message encoding via computerized alternative communication systems by cerebral-palsied users. A 13-year-old illiterate cerebral-palsied girl was exposed to a computerized version, with digitized voice of Maharaj’s Pictogram Ideogram Communication. For seven years prior to the study, the girl had failed to use Blissymbols in communication boards. The present study compared the difficulty of pictorial message encoding under visual and auditory stimulation (i.e., describing observed events versus transcribing heard sentences). The latter proved easier than the former, suggesting that the pictorial system was indexed auditorily in the girl’s lexicon. Such an indexing is attributed to the intensive practice with digitized speech. This allows for the phonological encoding of pictorial information, resulting in an increase in the working memory capacity and steady progress in the functional use of a communication system.