Micro-switch programmes for students with multiple disabilities and minimal motor behaviour: assessing response acquisition and choice

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.

Speech and language therapists' approaches to communication intervention with children and adults with profound and multiple learning disability

BACKGROUND

People with profound intellectual and multiple disabilities (PMLD) have communication impairments as one defining characteristic.

AIMS

To explore speech and language therapists' (SLTs) decision making in communication interventions for people with PMLD, in terms of the intervention approaches used, the factors informing the decisions to use specific interventions and the extent to which the rationales underpinning these decisions related to the components of evidence based practice (EBP), namely empirical evidence, clinical experience and client/carer views and values.

METHODS & PROCEDURES

A questionnaire on communication assessment and intervention for people with PMLD was sent to SLTs in the UK to elicit information on: the communication intervention approaches they used; their rationales for their intervention choices; their use of published evidence to inform decision making.

OUTCOMES & RESULTS

Intensive interaction and objects of reference were the communication interventions most often used with people with PMLD, with some differences between children and adults evident. Rationales provided conformed somewhat to the EBP framework though extension of the existing framework and addition of practical and organizational considerations led to a revised typology of rationale for decision making. Rationales most frequently related to the empowerment, development and behavioural preferences of the person with PMLD.

CONCLUSIONS & IMPLICATIONS

Empirical research evidence was seldom mentioned by SLTs as informing intervention decision making leading to very diverse practice. There is a need for further research on the effectiveness of commonly used but under-evaluated interventions. There is also a need to alert SLTs to the evidence base supporting other approaches, particularly switch-based, cause and effect approaches.

Persons with Acquired Brain Injury and Multiple Disabilities Access Stimulation Independently through Microswitch-Based Technology

The possibility of enabling two adults with acquired brain injury and profound multiple disabilities to use microswitch-based technology to attain preferred environmental stimuli on their own was assessed. Each of the participants was provided with two microswitches that could be activated by right and left head-turning or head-bending responses. The microswitches were introduced sequentially according to a multiple probe design across microswitches (responses) and allowed access to different sets of auditory or visual stimuli. Eventually, the two microswitches were made available simultaneously. Sessions lasted 5 min. Each participant learned to use the two microswitches successfully and maintained consistent levels of responding when they were simultaneously available. During this phase, both participants showed large within-session variations in their right and left response frequencies, with one of them showing an overall prevalence of the left-side response. The importance of assistive technology within programs for persons with acquired brain injury and multiple disabilities is discussed.

Helping a man with multiple disabilities to use single vs repeated performance of simple motor schemes as different responses

A man with multiple disabilities was taught to use single vs repeated performance of simple motor schemes as different responses. Specifically, single and double emissions of a finger movement served as two separate responses, which allowed direct access to different environmental stimuli via microswitch technology. Single and double emissions of a head movement served as two additional responses, which allowed interaction with two different caregivers who were called via voice output communication aids (VOCAs). The results showed that the man, who had pervasive motor impairment, acquired the four responses available and seemed to use them purposefully. The implications of this approach to increase the response options of persons with few controllable motor schemes were discussed.

Microswitch- and VOCA-assisted programs for two post-coma persons with minimally conscious state and pervasive motor disabilities

Intervention programs, based on learning principles and assistive technology, were assessed in two studies with two post-coma men with minimally conscious state and pervasive motor disabilities. Study I assessed a program that included (a) an optic microswitch, activated via double blinking, which allowed a man direct access to brief music intervals, and (b) a voice output communication aid (VOCA) with two channels, activated via different hand-closure movements, which allowed the man to call his mother and a research assistant who provided stimulation events. Study II assessed a program that included (a) a pressure microswitch, activated via head movements, which allowed a man direct access to video-clips and music, and (b) a VOCA device, activated via prolonged eyelid closure, which allowed the man to call the caregiver (i.e., a research assistant) who provided attention and sung to him. Each of the two participants had significant increases in both microswitch- and VOCA-related responses during the intervention phases of the studies. Moreover, purposeful choice seemed to occur between the two VOCA responses in Study I. Implications of the findings for improving the situation of post-coma persons with minimally conscious state and pervasive motor disabilities are discussed.

Two persons with multiple disabilities use a mouth-drying response to reduce the effects of their drooling

These two studies involved a boy and a man with multiple disabilities, who were taught to use a mouth-drying response to reduce the effects of their drooling. Both studies relied on microswitch technology to monitor the drying response and follow it with positive stimulation (i.e., during intervention). In Study I, the boy performed the drying response via a special napkin. The microswitch technology consisted of touch/pressure sensors and a radio transmitter hidden inside the napkin. Drying responses led the boy to 8s of preferred stimulation. In Study II, the man performed the drying response via a handkerchief. The microswitch technology consisted of an optic sensor and a radio transmitter at the man's chest. Drying responses led the man to 8-10s of preferred stimulation. The stimulation time/conditions were subsequently modified to promote a reduction in the man's response frequency. The experimental design involved an ABAB sequence (Study I) or an ABABB(1)B(2) sequence (Study II), with the second B or the B(1)B(2) combination spreading over periods of about 3 months. The results indicated vast increases in drying responses and decreases in chin wetness during the intervention phases. The frequencies of the drying response remained consistent for the boy and stabilized at a lower level (i.e., in line with the manipulation of the stimulation conditions) for the man. Implications of the findings and limitations of the studies are discussed.

Persons with multiple disabilities accessing stimulation and requesting social contact via microswitch and VOCA devices: new research evaluation and social validation

The first of these two studies assessed whether 11 participants with multiple disabilities of 5.3-18.2 (M=10.7) years of age would succeed in combining a microswitch for accessing preferred environmental stimuli and a Voice Output Communication Aid (VOCA) for requesting social contact. The second study conducted a social validation assessment of the aforementioned microswitch-VOCA combination. Data showed that all participants learned to use the microswitch and the VOCA. Moreover, the 10 participants, who received a 1-month post-intervention check, largely maintained their responding. The social validation assessment indicated that the raters (i.e., 110 university psychology students) favored the combination of microswitch and VOCA over the microswitch or the VOCA alone, and hypothetical combinations of microswitches or VOCAs.

Students with multiple disabilities using technology-based programs to choose and access stimulus events alone or with caregiver participation

The first of these two studies extended preliminary evidence on the use of technology-based programs for enabling students with severe and profound multiple disabilities to choose and access environmental stimuli on their own. Each of the three participants had two microswitches linked to specific sets of stimuli through a computer system. The activation of one of the microswitches triggered the computer system to present a sample of one of the stimuli. If the student chose it, the computer system turned it on for a specific time interval. The second study tested a new technology that allowed the students to choose and access the chosen stimuli with the involvement of the caregiver. The two participants had three microswitches linked to a computer system. The participants' choice of a stimulus alerted the caregiver who then got involved in the stimulation process. The results of both studies showed that the participants learned to activate the basic microswitches consistently, had high percentages of choice for the stimulus samples presented by the computer but with wide differences across stimuli, and largely maintained this performance at a 2-month post-intervention check. These findings were analyzed in terms of the usability of the two types of programs, the role they may play within educational and living contexts, and their innovative technical dimensions.

Use of a Mouth-Wiping Response to Reduce Drooling by Two Persons With Profound Developmental Disabilities

Two men with profound developmental disabilities used a mouth-wiping response instrumental to reduce drooling via a micro-switch-based program (i.e., a program in which the response was automatically monitored and followed by positive stimulation). The wiping response was performed via a napkin or a handkerchief placed inside a belt pocket. The micro-switch technology consisted of two mini-tilt sensors and a radio transmitter hidden inside the napkin, or an optic sensor and a radio transmitter fixed inside the belt pocket. The study was carried out according to a multiple baseline across participants and included a 3-month postintervention check. During the baseline, the participants' mean frequencies of mouth wiping were near zero, and mean percentages of wet chin intervals were about 45 and 50. During the intervention, the mean wiping frequencies increased to 1.6 and 1.9 per min, whereas the mean percentages of wet-chin intervals were mostly below 10. These values were maintained at the postintervention check. Implications of the findings and limitations of the study are discussed.

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.

Three persons with multiple disabilities accessing environmental stimuli and asking for social contact through microswitch and VOCA technology

BACKGROUND

Direct access to environmental stimuli and opportunity to ask for social contact/attention may be considered highly relevant objectives for persons with multiple disabilities. We assessed the possibility of enabling three of these persons (two children and one adolescent) to combine two microswitches (for accessing environmental stimuli) and a Voice Output Communication Aid (VOCA), which allowed them to ask for caregiver's attention.

METHODS

Initially, the participants were required to use each of the two microswitches individually and then together. Thereafter, they were taught to use the VOCA. Eventually, the VOCA was available together with the microswitches, and the participants could use any of the three.

RESULTS

The results, which support preliminary data on this topic, showed that all participants (1) were able to operate the two microswitches as well as the VOCA; and (2) used all three of them consistently when they were simultaneously available.

CONCLUSIONS

Teaching persons with multiple disabilities to combine a VOCA with conventional microswitches may enrich their general input, emphasize their active social role and eventually enhance their social image.

Enabling two persons with multiple disabilities to access environmental stimuli and ask for social contact through microswitches and a VOCA

This study assessed the combination of two microswitches with a voice output communication aid (VOCA) with two persons (an adolescent and a young adult) with multiple disabilities. The microswitches allowed the participants to obtain direct access to preferred environmental stimuli; the VOCA enabled them to ask for caregiver's attention. Initially, the participants were taught to use each of the two microswitches individually and then together. Next, they were taught to use the VOCA and, eventually, this was available together with the microswitches. Results showed that the participants learned to operate the microswitches and the VOCA and used all three of them consistently when they were simultaneously available. Implications of these findings and the potential role of a VOCA combined with conventional microswitches were discussed.

A brief account of statistical tests for single-case research with persons with developmental disabilities

Education and rehabilitation research with persons with developmental disabilities is often based on single-case designs (with small numbers of ordinal data points collected at irregular intervals) and relies upon graphic display and visual inspection of the data. This paper (a) provides a brief account of some statistical tests, which may serve to supplement the visual inspection process and (b) underlines some of their strengths and limitations to help education and rehabilitation personnel make a reasonable choice among them.

Multiple microswitches for persons with multiple disabilities: a basic procedure to examine the persons' choice behavior

This study examined a basic choice-analysis procedure to clarify choice between two responses and related stimuli by five persons with multiple disabilities ages 17.1 to 50.2 yr. The procedure was based on reversing the links between responses and stimuli to assess whether the stimuli accounted for differences in response levels. When this was not the case, the procedure added extra stimuli for the less preferred response to judge whether such an increase would compensate for the apparent disadvantage of that response, e.g., its higher physical cost. Analysis showed that the choice of three of the five participants seemed motivated by the stimuli following the responses. The choice of the other two persons seemed related to a preference for one of the responses which was partially or largely modified when extra stimuli were added.