Acquisition and functional use of voice output communication by persons with profound multiple disabilities

Effects of Interventions Involving Speech Output Technologies on Communication Outcomes for Individuals With Developmental Disabilities: A Scoping Review

PURPOSE

This scoping review aimed to map the literature on the effects of interventions involving speech output technologies on communication outcomes for individuals with developmental disabilities other than autism spectrum disorder.

METHOD

A scoping review methodology was used to limit bias in searching, selecting, coding, and synthesizing relevant intervention studies. This involved a multifaceted search for studies conducted between 1991 and March 2021 using various electronic databases, ancestry searches, and forward citation searches from selected articles. Studies had to meet stringent inclusion criteria. Each study was summarized in terms of authors, purpose, participants, design, speech output, outcomes, effectiveness, and quality appraisal.

RESULTS

Twenty-five single-case experimental design studies (88 participants) and one group design studies (62 participants) qualified for inclusion. Most of the participants had multiple diagnoses followed by a diagnosis of cerebral palsy and Down syndrome. Most studies focused on requesting behaviors and to a much lesser extent on syntactic structure and word identification. A dearth of high-quality studies was identified.

CONCLUSIONS

Overall, there is a paucity of high-quality research investigating the effects of speech output technologies for children with developmental disabilities. Additionally, several directions for future research are posited.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20468928.

Efficacy of a novel augmentative and alternative communication system in promoting requesting skills in young children with Autism Spectrum Disorder in India: A pilot study

Background & aims: The study assessed the efficacy of a novel, child-friendly, socio-culturally sensitive, icon-based Augmentative and Alternative Communication (AAC) system called Jellow Communicator, in teaching requesting skills to young children with Autism Spectrum Disorder (ASD) in a special school in Mumbai, India. Jellow is a comprehensive AAC system with a lexicon and pictorial library designed using a participatory, user-centric design process. The content of Jellow has been developed bearing in mind the socio-cultural and linguistic diversity of India. Jellow is available in low-tech (flashcards, booklet) and high-tech (Android and iOS app and desktop application) versions. Methods: The quasi-experimental longitudinal study involved seventeen 3.5-12-year-old children with ASD with communication challenges. Children were taught to use the Jellow AAC system to request for preferred items, as part of their regular speech therapy sessions. Each child received one-on-one training sessions with a licensed speech therapist twice a week over a 3-month duration, with each session lasting around 20-30 min. A systematic training protocol adapted from the original Picture Exchange Communication System (PECS) was developed to train children to use the Jellow system, progressing from flashcards to the app version of Jellow. Behavioral training strategies such as modeling, least-to-most prompting, differential reinforcement, and behavior chain interruption were used to facilitate requesting behaviors. The speech therapist assessed children's developmental level across multiple domains at pretest and posttest. We coded 3 videos per child, i.e., one early, one mid, and one late training session each, to assess changes in children's stage of communication, spontaneous requesting abilities, level of attention during training trials, and average time to completion for requesting trials. In addition, caregivers filled out questionnaires to assess training-related changes in children's adaptive functioning levels as well as the psychosocial impact of the Jellow AAC system on children's quality of life. Results: Children significantly improved their stage of communication, and a majority of children transitioned from flashcards to using the Jellow app to request for preferred items. Children also increased the proportion of spontaneous requests over the course of training. Caregivers reported a positive perceived psychosocial impact of the Jellow AAC system on their child's self-esteem, adaptability, and competence. Conclusions: The findings from our pilot study support the use of the novel, socio-culturally adapted, Jellow Communicator AAC system for teaching requesting skills to young children with ASD who use multiple communication modalities. Future studies should replicate our findings with a larger group of participants using a randomized controlled trial design. Implications: This is the first experimental study to systematically assess the effects of an indigenously-developed comprehensive AAC system adapted to the sociocultural and linguistic landscape of India. Our study results provide support for the use of the cost-effective Jellow Communicator AAC system in facilitating requesting skills in children with ASD who use multiple communication modalities. Clinicians can use low-tech and high-tech versions of Jellow to promote communication skills in children with ASD.

Comparing Single Case Design Overlap-Based Effect Size Metrics From Studies Examining Speech Generating Device Interventions

Meaningfully synthesizing single case experimental data from intervention studies comprised of individuals with low incidence conditions and generating effect size estimates remains challenging. Seven effect size metrics were compared for single case design (SCD) data focused on teaching speech generating device use to individuals with intellectual and developmental disabilities (IDD) with moderate to profound levels of impairment. The effect size metrics included percent of data points exceeding the median (PEM), percent of nonoverlapping data (PND), improvement rate difference (IRD), percent of all nonoverlapping data (PAND), Phi, nonoverlap of all pairs (NAP), and Tau(novlap). Results showed that among the seven effect size metrics, PAND, Phi, IRD, and PND were more effective in quantifying intervention effects for the data sample (N = 285 phase or condition contrasts). Results are discussed with respect to issues concerning extracting and calculating effect sizes, visual analysis, and SCD intervention research in IDD.

Teaching Individuals to Signal for Assistance in a Timely Manner

The study describes the adaptive-switch performances of 8 adults with severe multiple impairments. Each was given a series of progressively more difficult discrimination tasks that, if solved, would require the participant to close the switch to activate a device that was not operating or to stay away from the switch if the device was operating. Then in a 2-choice format, a preference test was conducted by providing 2 devices simultaneously that could be activated or deactivated by closure or release of the switch. Finally, a preferred device was activated and then surreptitiously deactivated. Switch closures in this contingency activated a speech-generating device that played the message, "Help me." All 8 participants learned to control devices using their adaptive switch, but only 4 participants learned to make a request for help. Reasons for the different performances across learners and nonlearners are discussed.

Supported decision-making and personal autonomy for persons with intellectual disabilities: article 12 of the UN convention on the rights of persons with disabilities

Making decisions is an important component of everyday living, and issues surrounding autonomy and self-determination are crucial for persons with intellectual disabilities. Article 12 (Equal Recognition before the Law) of the UN Convention on the Rights of Persons with Disabilities addresses this issue of decision-making for persons with disabilities: the recognition of legal capacity. Legal capacity means recognizing the right to make decisions for oneself. Article 12 is also moving in the direction of supported decision-making, as an alternative to substituted decision-making. The objective of this paper is to show conceptually the connection between supported decisionmaking and the preservation of personal autonomy for persons with intellectual disabilities. This paper discusses supported decision-making based on Bach and Kerzner's model: (a) legally independent status, (b) supported decision- making status, and (c) facilitated decision-making status. Arguments will be made based on John Stuart Mill's concept of autonomy and arguments against it using Sarah Conly's argument for paternalism.

The use of speech generating devices in communication interventions for individuals with developmental disabilities: a review of the literature

OBJECTIVE

This review synthesizes communication interventions that involved the use of speech generating devices (SGD) for individuals with developmental disabilities.

METHODS

Systematic searches of electronic databases, journals and reference lists identified 35 studies meeting the inclusion criteria. These studies were evaluated in terms of (a) participants, (b) SGD function, (c) SGD characteristics, (d) intervention procedures, (e) intervention results and (f) certainty of evidence.

RESULTS

Across these studies, intervention was provided to a total of 86 participants aged 1-42 years. Communication skills targeted included requesting, social or conversational skills, labelling items and receptive language. Intervention approaches were categorized as using Discrete Trial Training, Milieu teaching or a combined instructional approach. Positive outcomes were reported in 86% of the studies with 54% of studies categorized as providing conclusive evidence.

CONCLUSION

This literature base is considered promising due to the large number of conclusive studies and the replication of intervention approaches.

Behavioral Intervention Promotes Successful Use of an iPod-Based Communication Device by an Adolescent With Autism

Individuals with autism and limited speech are candidates for speech-generating devices (SGDs), but some individuals might experience difficulty in operating these devices. We describe the case of Steven, a 17-year-old adolescent with autism who used an iPod-based SGD, but had difficulty activating the speech output feature of this device. His difficulties were initially interpreted as motor control problems, suggesting the need to abandon this technology, prescribe a different SGD, or adapt his existing device. An alternative conceptualization was that the existing intervention procedures had failed to shape more effective response topographies. Along these lines, a behavioral intervention, involving differential reinforcement and delayed prompting, proved effective in shaping response topographies that enabled Steven to be more successful in activating the speech output function of his iPod-based SGD. The results suggest that behavioral intervention may provide an alternative to the more costly and involved process of replacing or modifying the person’s SGD.

Transferring AAC intervention to the home

PURPOSE

To evaluate the acquisition of AAC skills during an initial clinical trial and assess subsequent transfer of the training to the home setting.

METHOD

A 12-year-old male with autism was first seen in a clinical setting to establish the use of a voice-output communication device. After learning to use the device to request access to preferred objects in the clinical trial, the intervention was transferred to the home. Follow-up with the parent was conducted via e-mail and telephone. Videotapes were made of initial home-based sessions to enable evaluation of the participant's progress.

RESULTS

The programme was successful in teaching the participant to use a portable AAC device to make requests during the clinical trial and then in two home-based activities.

CONCLUSION

An initial clinical trial with follow-up support for parents may be an efficient method for beginning AAC intervention and transferring the training procedures to the home setting.

PECS and VOCAs to enable students with developmental disabilities to make requests: an overview of the literature

This paper provides an overview of the literature dealing with the use of the Picture Exchange Communication System (PECS) and voice output communication aids (VOCAs) for promoting the performance of requests by students with developmental disabilities. Computerized and manual searches were carried out to identify the studies published during the last 15 years (i.e., the period between 1992 and 2006 during which PECS and VOCA approaches became popular). Thirty-seven studies were identified and then divided into three groups concerning the use of the PECS or equivalents, the use of VOCAs or equivalents, and the comparison of both these approaches, respectively. Of the 173 students involved in studies using the PECS or equivalents only three could be considered failures, while a fourth one did not progress in the program due to illness. Similarly, of the 39 students who used VOCAs or equivalents only three could be considered failures, while one was partly successful. Finally, of the 11 students involved in the comparisons between PECS and VOCAs none could be classified as a failure. The results are very encouraging but methodological concerns and the relatively limited use of the systems in terms of request items and request opportunities suggest caution. Caution may also be needed in interpreting the reported similarities between the two systems in usability and effectiveness.

Considering student choice when selecting instructional strategies: a comparison of three prompting systems

Three secondary age students with moderate intellectual disabilities learned to use the system of least prompts, a self-operated picture prompting system, and a self-operated auditory prompting system to use a copy machine and a debit machine. Both the effectiveness and efficiency of these prompting systems were compared. Additionally, student preference of instructional method was examined. The results demonstrated that each prompting system was effective and efficient with varying students when skill acquisition and duration of task performance were measured. All students demonstrated increased independence in completing both tasks. This study found that the preferred prompting systems were more effective in terms of both skill acquisition and duration for completing tasks for students.

Teaching VOCA use as a communicative repair strategy

Students with developmental disabilities often rely on prelinguistic behavior (e.g., reaching, leading) to communicate. When listeners fail to attend to prelinguistic behaviors, students may benefit from responding with an alternative form of communication to repair the breakdown. In the present study, we taught two students with developmental disabilities to repair communicative breakdowns by using a voice-output communication aid (VOCA). Intervention occurred at morning snack time when the students had the opportunity to access preferred items through prelinguistic behavior (e.g., reaching, guiding). Breakdowns occurred when the listener failed to attend to the student's initial request. Effects of the intervention were evaluated in a multiple-baseline design across subjects. Both students learned to use the VOCA to repair communicative breakdowns. As VOCA use was acquired as a repair strategy, the students also began to use the device to initiate requests when there had been no breakdown in communication. The intervention appeared to be an effective approach for supplementing prelinguistic behaviors with an additional option for communicating a request.

Teaching students with developmental disabilities to locate their AAC device

Students with autism and related developmental disabilities who do not speak are often taught to use some type of augmentative and alternative communication (AAC) system, such as a voice output communication aid (VOCA). One problem with such devices is that the person may be unable to communicate when the device is not readily accessible. We first taught three nonverbal students with autism to use a VOCA to request access to preferred items. Following this initial acquisition phase, however, none of the students would locate their VOCA when it was not within reach. A least-to-most prompting procedure was implemented to teach the students to locate their AAC device. The effectiveness of this procedure for teaching VOCA location skills was evaluated in a delayed multiple-baseline across subjects design. The results showed that the intervention was effective in teaching the students to locate their AAC device when they needed it to request access to preferred objects. Teaching VOCA location skills may be a useful and necessary component in AAC interventions for some people with developmental disabilities.

A microswitch program including words and choice opportunities for students with multiple disabilities

Two students with multiple disabilities were provided with two or three request microswitches and one choice microswitch. Activation of a request microswitch triggered the verbal announcement of one of the stimulus events related to it. The student could choose such an event through the choice microswitch or bypass it. The request microswitches were introduced individually and made available simultaneously by the end of the intervention and the postintervention period. Analysis showed that both students learned to use the microswitches. Transfer of the microswitch program into the students' home was very successful with one student and presented some difficulties with the other. Implications of the findings and new possible developments were discussed.

Extending microswitch-based programs for people with multiple disabilities: use of words and choice opportunities

This study assessed a microswitch-based program in which three request and one choice microswitches were used for two participants with multiple disabilities. The program was then transferred into the participants' daily contexts. Each request microswitch was linked to different stimulation opportunities. Every activation of the microswitch triggered the verbal announcement of one such opportunity that the participant could choose or bypass. The request microswitches were introduced individually and then combined. During the last part of the intervention and the post-intervention checks, all three request microswitches plus the choice microswitch were simultaneously available. Both participants learned to use the microswitches very rapidly. Responding levels were high during intervention and the post-intervention checks carried out in the participants' daily contexts. Implications of the findings for advanced microswitch-based programs and vocal recognition technology are discussed.

Evaluating the use of multiple microswitches and responses for children with multiple disabilities

BACKGROUND

The present study assessed the feasibility of (1) establishing multiple microswitches and responses (some of which had not been used before) with two children with multiple disabilities, and (2) maintaining such microswitches and responses in the children's daily contexts.

METHODS

The microswitches were introduced individually and then combined. During the last part of treatment and the follow-up, each child had three microswitches.

RESULTS

The data show that both children learned to use all three available microswitches. Moreover, they retained fairly high levels of responding with the microswitches in their daily contexts during follow-up periods of 4 and 6 months.

CONCLUSIONS

The personal and practical implications of these findings are discussed.

Use of microswitches and speech output systems with people with severe/profound intellectual or multiple disabilities: a literature review

Microswitches and speech output systems are two forms of technology which have been used with people with severe/profound intellectual or multiple disabilities to help them reduce their isolation and interact with the surrounding world (i.e., thus obtaining environmental stimulation independently or requesting it efficiently). This paper reviews the studies which used microswitches and speech output systems with the aforementioned people during the 1986-1999 period, and discusses the research findings and the practicality of these two forms of technology. Some relevant issues for future research are also pointed out.

Increasing communicative interactions of young children with autism using a voice output communication aid and naturalistic teaching

We evaluated the effects of a voice output communication aid (VOCA) and naturalistic teaching procedures on the communicative interactions of young children with autism. A teacher and three assistants were taught to use naturalistic teaching strategies to provide opportunities for VOCA use in the context of regularly occurring classroom routines. Naturalistic teaching procedures and VOCA use were introduced in multiple probe fashion across 4 children and two classroom routines (snack and play). As the procedures were implemented, all children showed increases in communicative interactions using VOCAs. Also, there was no apparent reductive effect of VOCA use within the naturalistic teaching paradigm on other communicative behaviors. Teachers' ratings of children's VOCA communication, as well as ratings of a person unfamiliar with the children, supported the contextual appropriateness of the VOCA. Probes likewise indicated that the children used the VOCAs for a variety of different messages including requests, yes and no responses, statements, and social comments. Results are discussed in regard to the potential benefits of a VOCA when combined with naturalistic teaching procedures. Future research needs are also discussed, focusing on more precise identification of the attributes of VOCA use for children with autism, as well as for their support personnel.