Informativeness ratings of messages created on an AAC processing prosthesis

Abstract

Background: SentenceShaper ^™ (SSR) is a computer program that supports spoken language production in aphasia by recording and storing the fragments that the user speaks into the microphone, making them available for playback and allowing them to be combined and integrated into larger structures (i.e., sentences and narratives). A prior study that measured utterance length and grammatical complexity in story‐plot narratives produced with and without the aid of SentenceShaper demonstrated an “aided effect” in some speakers with aphasia, meaning an advantage for the narratives that were produced with the support of this communication aid (Linebarger, Schwartz, Romania, Kohn, & Stephens, 2000). The present study deviated from Linebarger et al.'s methods in key respects and again showed aided effects of SentenceShaper in persons with aphasia.

Aims: Aims were (1) to demonstrate aided effects in “functional narratives” conveying hypothetical real‐life situations from a first person perspective; (2) for the first time, to submit aided and spontaneous speech samples to listener judgements of informativeness; and (3) to produce preliminary evidence on topic‐specific carryover from SentenceShaper, i.e., carryover from an aided production to a subsequent unaided production on the same topic.

Methods & Procedures: Five individuals with chronic aphasia created narratives on two topics, under three conditions: Unaided (U), Aided (SSR), and Post‐SSR Unaided (Post‐U). The 30 samples (5 participants, 2 topics, 3 conditions) were randomised and judged for informativeness by graduate students in speech‐language pathology. The method for rating was Direct Magnitude Estimation (DME).

Outcomes & Results: Repeated measures ANOVAs were performed on DME ratings for each participant on each topic. A main effect of Condition was present for four of the five participants, on one or both topics. Planned contrasts revealed that the aided effect (SSR > U) was significant in each of these cases. For two participants, there was also topic‐specific carryover (Post‐U > U).

Conclusions: Listeners judged functional narratives generated on SentenceShaper to be more informative than comparable narratives spoken spontaneously. This extends the evidence for aided effects of SentenceShaper. There was also evidence, albeit weaker, for topic‐specific carryover, suggesting that the program might be used effectively to practise for upcoming face‐to‐face interactions.

The authors gratefully acknowledge the thoughtful review given to an earlier draft of this paper by Kathryn L. Garrett and an anonymous reader. We also thank Evelyn Klein, Assistant Professor of Speech‐Language‐Hearing Science at LaSalle University, and Jennifer Lowery, MA CCC/SLP, for their assistance with the coordination and execution of the listener ratings study, and Patrick J. Doyle for helpful discussions of DME methods. Support for this study was provided by a grant from the NIH (#1 R01 HD043991; P.I., M. Schwartz).

Notes

1. SentenceShaper uses methods and computer interfaces covered by U.S. Patent No. 6,068,485 (Linebarger & Romania, 2000) owned by Unisys Corporation and licensed to Psycholinguistic Technologies, Inc., which has released SentenceShaper as a commercial product. A potential conflict of interest arises because ML serves as Director of Psycholinguistic Technologies. Therefore, ML has not participated in testing or in scoring of raw data in the study reported here.

2. SentenceShaper is the latest version of a program whose earlier prototype went by the name “CS” for “Communication System”. From the user's perspective, CS and SentenceShaper are the same, except for cosmetic features such as changes to the colours, shapes, and/or location on the screen of program elements. Consequently, in sections of this paper that describe prior results with the program, past and current versions are not distinguished, and the current name, SentenceShaper, is applied to both. Interested readers are invited to compare the prototype's interface, depicted in Linebarger et al., 2000, with that of SentenceShaper, shown in Figure 1.