A microswitch-based programme to enable a boy with multiple disabilities and minimal motor behaviour to choose among environmental stimuli

A scoping review of AAC interventions for children and young adults with simultaneous visual and motor impairments: Clinical and research Implications

Individuals with multiple disabilities are among the most challenging to serve and AAC teams often lack direction in determining effective interventions. The purpose of this scoping review was to summarize the research evidence on AAC interventions for individuals with complex communication needs and simultaneous motor, and visual impairments as part of their multiple disabilities; to consider implications for practice; and to determine gaps and directions for future research. A total of 27 studies were identified and reviewed, involving 55 unique participants with multiple disabilities. Most studies focused on direct intervention to increase requesting or choice-making, with little focus on social communication. Only two studies focused on training communication partners. Results indicated that AAC interventions can be highly effective to increase communication for individuals with multiple disabilities. However, there is an urgent need for increased rigor and more detailed participant information in future AAC intervention research with this population. Future research should investigate AAC intervention to improve social communication and increase language development, not just expression of needs and wants. Future research should focus on the needs of individuals with multiple disabilities from culturally and linguistically diverse backgrounds and on implementation of AAC within natural environments.

Enabling Persons with Multiple Disabilities to Choose among Environmental Stimuli and Request Stimulus Repetitions through Microswitch and Computer Technology

This study assessed microswitch and computer technology to enable two participants with multiple disabilities, 32 and 19 years of age, to choose among environmental stimuli and request their repetition whenever they so desired. Within each session, 18 stimuli (12 preferred and 6 nonpreferred) were available. For each stimulus, a computer system provided a sample of 3 sec. duration. During the intervention, participants' vocal responding in relation to a stimulus sample activated a microswitch and a computer system turned on that stimulus for 15–30 sec. When participants did not vocally respond, the computer system paused briefly and then presented the next scheduled stimulus sample. When participants vocally responded at the end of a stimulus presentation, the stimulus was repeated. Intervention data showed that the participants learned to choose preferred stimuli and bypass nonpreferred ones as well as to request repetitions of the preferred stimuli. This performance was maintained at a 1-mo. postintervention check and transferred to sets of stimuli not used in the intervention. The implications of these results were discussed.

Enabling Two Adolescents with Multiple Disabilities to Choose among Environmental Stimuli through Different Procedural and Technological Approaches

Two single-case studies were carried out using different procedural and technological approaches to enable two adolescents with multiple disabilities to choose among environmental stimuli. Study I focused on replicating a recently developed procedure, which relied on samples of the auditory stimuli available as cues for choice responses. Study II assessed a new procedural and technical setup relying on the use of pictorial representations of the stimuli available as cues for choice responses. The auditory samples and the pictorial representations were presented through computer systems. The participants' choice responses relied on microswitches connected to the computer systems. The data of Study I fully supported previous findings with the same procedural approach. The participant learned to choose preferred stimuli and bypass nonpreferred ones. The data of Study II showed that the participant learned to concentrate his choice responses on a few stimuli, suggesting that these stimuli were actually preferred and that responding was purposeful. Implications of the results were discussed.

Single-Trial Analysis of Inter-Beat Interval Perturbations Accompanying Single-Switch Scanning: Case Series of Three Children With Severe Spastic Quadriplegic Cerebral Palsy

Single-switch access in conjunction with scanning remains a fundamental solution in restoring communication for many children with profound physical disabilities. However, untimely switch inaction and unintentional switch activations can lead to user frustration and impede functional communication. A previous preliminary study, in the context of a case series with three single-switch users, reported that correct, accidental and missed switch activations could elicit cardiac deceleration and increased phasic skin conductance on average, while deliberate switch non-use was associated with autonomic nonresponse. The present study investigated the possibility of using blood volume pulse recordings from the same three pediatric single-switch users to track the aforementioned switch events on a single-trial basis. Peaks of the line length time series derived from the empirical mode decomposition of the inter-beat interval time series matched, on average, a high percentage (above 80%) of single-switch events, while unmatched peaks coincided moderately (below 37%) with idle time during scanning. These results encourage further study of autonomic measures as complementary information channels to enhance single-switch access.

Autonomic responses to correct outcomes and interaction errors during single-switch scanning among children with severe spastic quadriplegic cerebral palsy

BACKGROUND

The combination of single-switch access technology and scanning is the most promising means of augmentative and alternative communication for many children with severe physical disabilities. However, the physical impairment of the child and the technology's limited ability to interpret the child's intentions often lead to false positives and negatives (corresponding to accidental and missed selections, respectively) occurring at rates that frustrate the user and preclude functional communication. Multiple psychophysiological studies have associated cardiac deceleration and increased phasic electrodermal activity with self-realization of errors among able-bodied individuals. Thus, physiological measurements have potential utility at enhancing single-switch access, provided that such prototypical autonomic responses exist in persons with profound disabilities.

METHODS

The present case series investigated the autonomic responses of three pediatric single-switch users with severe spastic quadriplegic cerebral palsy, in the context of a single-switch letter matching activity. Each participant exhibited distinct autonomic responses to activity engagement.

RESULTS

Our analysis confirmed the presence of the autonomic response pattern of cardiac deceleration and increased phasic electrodermal activity following true positives, false positives and false negatives errors, but not subsequent to true negative outcomes.

CONCLUSIONS

These findings suggest that there may be merit in complementing single-switch input with autonomic measurements to improve augmentative and alternative communications for pediatric access technology users.

Persons with multiple disabilities select environmental stimuli through a smile response monitored via camera-based technology

OBJECTIVE

To assess whether two persons with multiple disabilities could use smile expressions and new camera-based microswitch technology to select environmental stimuli.

METHOD

Within each session, a computer system provided samples/reminders of preferred and non-preferred stimuli. The camera-based microswitch determined whether the participants had smile expressions in relation to those samples. If they did, stimuli matching the specific samples to which they responded were presented for 20 seconds.

RESULTS

The smile expression could be profitably used by the participants who managed to select means of ∼70% or 75% of the preferred stimulus opportunities made available by the environment while avoiding almost all the non-preferred stimulus opportunities.

CONCLUSION

Smile expressions (a) might be an effective and rapid means for selecting preferred stimulation and (b) might develop into cognitively more elaborate forms of responding through the learning experience (i.e. their consistent association with positive/reinforcing consequences).

Microswitch-Based Programs for Persons with Multiple Disabilities: An Overview of Some Recent Developments

Persons with multiple disabilities are often unable to interact with their environment due to their limited response repertoire. Microswitch programs are designed to help them control environmental events, generally preferred stimulation, through simple (feasible) responses. To make microswitch programs a more widely usable and relevant resource for intervention with these persons, a number of new developments were pursued in recent years. This paper examines three of those developments as specifically addressed in our research activity, namely, (a) assessment of new, nontypical responses and matching microswitches, (b) fostering of multiple responses and exercise of choice, and (c) targeting of habilitative and clinical (therapeutic) objectives. The encouraging outcomes of these developments are reviewed in relation to their potentially wide implications for daily practice and the need of additional developments in the area.