Access to environmental stimulation via eyelid responses for persons with acquired brain injury and multiple disabilities: a new microswitch arrangement

Music Stimulation for People with Disorders of Consciousness: A Scoping Review

Music stimulation is considered to be a valuable form of intervention for people with severe brain injuries and prolonged disorders of consciousness (i.e., unresponsive wakefulness/vegetative state or minimally conscious state). This review was intended to provide an overall picture of work conducted during the last decade to assess the impact of music on behavioral and non-behavioral responses of people with disorders of consciousness. Following the PRISMA-ScR checklist, a scoping review was carried out to identify and provide a synthesis of eligible studies published in English during the 2010–2021 period. Three databases (i.e., PubMed, PsycINFO, and Web of Science) were employed for the literature search. Thirty-four studies met the inclusion criteria. Those studies were grouped into three categories based on whether they assessed the effects of: (i) recorded music, (ii) interactive music, or (iii) response-contingent music. A narrative synthesis of the studies of each of the three categories was eventually provided. While the studies of all three categories reported fairly positive/encouraging results, several methodological questions make it difficult to draw conclusions about those results and their implications for intervention programs in daily contexts.

Assistive technology to help persons in a minimally conscious state develop responding and stimulation control: Performance assessment and social rating

BACKGROUND

Post-coma persons in a minimally conscious state (MCS) and with extensive motor impairment and lack of speech tend to be passive and isolated.

OBJECTIVE

This study aimed to (a) further assess a technology-aided approach for fostering MCS participants' responding and stimulation control and (b) carry out a social validation check about the approach.

METHODS

Eight MCS participants were exposed to the aforementioned approach according to an ABAB design. The technology included optic, pressure or touch microswitches to monitor eyelid, hand or finger responses and a computer system that allowed those responses to produce brief periods of positive stimulation during the B (intervention) phases of the study. Eighty-four university psychology students and 42 care and health professionals were involved in the social validation check.

RESULTS

The MCS participants showed clear increases in their response frequencies, thus producing increases in their levels of environmental stimulation input, during the B phases of the study. The students and care and health professionals involved in the social validation check rated the technology-aided approach more positively than a control condition in which stimulation was automatically presented to the participants.

CONCLUSIONS

A technology-aided approach to foster responding and stimulation control in MCS persons may be effective and socially desirable.

Technology-aided programs for post-coma patients emerged from or in a minimally conscious state

Post-coma persons in a minimally conscious state (MCS) or emerged/emerging from such state (E-MCS), who are affected by extensive motor impairment and lack of speech, may develop an active role and interact with their environment with the help of technology-aided intervention programs. Although a number of studies have been conducted in this area during the last few years, new evidence about the efficacy of those programs is warranted. These three studies were an effort in that direction. Study I assessed a technology-aided program to enable six MCS participants to access preferred environmental stimulation independently. Studies II and III assessed technology-aided programs to enable six E-MCS participants to make choices. In Study II, three of those participants were led to choose among leisure and social stimuli, and caregiver interventions automatically presented to them. In Study III, the remaining three participants were led to choose (a) among general stimulus/intervention options (e.g., songs, video-recordings of family members, and caregiver interventions); and then (b) among variants of those options. The results of all three studies were largely positive with substantial increases of independent stimulation access for the participants of Study I and independent choice behavior for the participants of Studies II and III. The results were analyzed in relation to previous data and in terms of their implications for daily contexts working with MCS and E-MCS persons affected by multiple disabilities.

Microswitch-aided programs with contingent stimulation versus general stimulation programs for post-coma persons with multiple disabilities

OBJECTIVE

Assessing the impact of microswitch-aided programs with contingent stimulation on response engagement (Study I) and post-session alertness (Study II) of post-coma participants with multiple disabilities.

METHOD

Study I included three participants whose scores on the Coma Recovery Scale-Revised (CRS-R) were 11 or 13. Study II included three participants whose CRS-R scores were 19, 13, and 14. In both studies, the participants received sessions with contingent stimulation (i.e., sessions in which activation of a microswitch with an eyelid or hand response produced 15 s of preferred stimulation) and sessions with general, non-contingent stimulation (i.e., stimulation lasted throughout the sessions).

RESULTS

Study I showed an increase in response engagement/frequencies only during the contingent stimulation sessions. Study II showed that the participants' level of vigilance after those sessions was higher than after non-contingent stimulation sessions.

CONCLUSION

Microswitch-aided programs with contingent stimulation would be more beneficial than programs with general/non-contingent stimulation.

New camera-based microswitch technology to monitor small head and mouth responses of children with multiple disabilities

OBJECTIVE

Assessing a new camera-based microswitch technology, which did not require the use of color marks on the participants' face.

METHOD

Two children with extensive multiple disabilities participated. The responses selected for them consisted of small, lateral head movements and mouth closing or opening. The intervention was carried out according to a multiple probe design across responses. The technology involved a computer with a CPU using a 2-GHz clock, a USB video camera with a 16-mm lens, a USB cable connecting the camera and the computer, and a special software program written in ISO C++ language.

RESULTS

The new technology was satisfactorily used with both children. Large increases in their responding were observed during the intervention periods (i.e. when the responses were followed by preferred stimulation).

CONCLUSION

The new technology may be an important resource for persons with multiple disabilities and minimal motor behavior.

Occupation and communication programs for post-coma persons with or without consciousness disorders who show extensive motor impairment and lack of speech

These two studies were aimed at extending the assessment of technology-aided programs for post-coma persons with extensive motor impairment and lack of speech. Specifically, Study I assessed a new program arrangement, in which stimulation access and caregiver attention could be obtained with variations of the same response (i.e., single- versus double-hand closure) by three participants who were diagnosed at the upper level of the minimally conscious state at the start of the study. Study II was aimed at enabling two persons who had emerged from a minimally conscious state to engage in leisure activities, listen to audio-recordings of family members, and send and receive messages. The responses selected for these participants were hand pressure and eyelid closure, respectively. The results of both studies were positive. The participants of Study I increased their responding to increase their stimulation input and caregiver interaction. The participants of Study II managed to successfully select all the options the program included (i.e., the leisure options, as well as the family and communication options). General implications of the programs and the related technology packages for intervention with post-coma persons with multiple disabilities are discussed.

Technology-based intervention programs to promote stimulation control and communication in post-coma persons with different levels of disability

Post-coma persons in a minimally conscious state and with extensive motor impairment or emerging/emerged from such a state, but affected by lack of speech and motor impairment, tend to be passive and isolated. A way to help them develop functional responding to control environmental events and communication involves the use of intervention programs relying on assistive technology. This paper provides an overview of technology-based intervention programs for enabling the participants to (a) access brief periods of stimulation through one or two microswitches, (b) pursue stimulation and social contact through the combination of a microswitch and a sensor connected to a speech generating device (SGD) or through two SGD-related sensors, (c) control stimulation options through computer or radio systems and a microswitch, (d) communicate through modified messaging or telephone systems operated via microswitch, and (e) control combinations of leisure and communication options through computer systems operated via microswitch. Twenty-six studies, involving a total of 52 participants, were included in this paper. The intervention programs were carried out using single-subject methodology, and their outcomes were generally considered positive from the standpoint of the participants and their context. Practical implications of the programs are discussed.

Assessing learning as a possible sign of consciousness in post-coma persons with minimal responsiveness

A learning test procedure based on operant principles may be useful in the diagnosis (and eventually rehabilitation) of post-coma persons with minimal responsiveness. This study was aimed at extending the evaluation of such a procedure with seven participants who presented with very limited behavior and apparently severe disorders of consciousness. The procedure was evaluated through an ABACB design, in which A represented baseline phases without stimulation, B intervention phases with brief stimulation periods contingent on specific responses of the participants, and C a control phase in which stimulation was available all the time. Increased responding during the B phases, as opposed to the A and C phases, was taken to indicate learning and possibly a non-reflective expression of phenomenal consciousness. All participants were also evaluated with the coma recovery scale-revised (CRS-R) prior to the start of the learning test procedure and at the end of it. The results of the learning test showed that all participants had significantly higher responding levels during the B phases. The CRS-R scores suggested minimally conscious state for four of them prior to the learning test and for five of them after the completion of the learning test. The implications of the findings are discussed in terms of potential and time cost of the learning test.

Technology-aided programs to enable persons with multiple disabilities to choose among environmental stimuli using a smile or a tongue response

Persons with multiple disabilities, including pervasive motor impairment, may have problems controlling even small responses (e.g., vocal emissions, finger movements, or prolonged eyelid closures) within time-sensitive situations, such as those involved in choice programs. Recent research has indicated that smile expressions can be used as functional choice responses for some of these persons. The present two studies were aimed at assessing the smile response for a child with congenital multiple disabilities and a tongue response for a post-coma man who had recovered his consciousness but presented with pervasive multiple disabilities. The first of the two studies represented a research extension (i.e., a new case with a slightly adapted microswitch technology) concerning the smile response, which had recently been evaluated with few other cases. The second study represented a new effort to assess the tongue response within a choice program and for a post-coma man with multiple disabilities. The results showed that the participants used the smile and the tongue responses successfully while they were apparently unsuccessful in using a slight head/chin movement response. Their choice behavior focused reliably on preferred stimuli and avoided non-preferred stimuli. Implications of the results are discussed.

Promoting adaptive behavior in persons with acquired brain injury, extensive motor and communication disabilities, and consciousness disorders

These two studies extended the evidence on the use of technology-based intervention packages to promote adaptive behavior in persons with acquired brain injury and multiple disabilities. Study I involved five participants in a minimally conscious state who were provided with intervention packages based on specific arrangements of optic, tilt, or pressure microswitches (linked to preferred environmental stimuli) and eyelid, toe and finger responses. Study II involved three participants who were emerging from a minimally conscious state and were provided with intervention packages based on computer presentations of stimulus options (i.e., preferred stimuli, functional caregiver's procedures, and non-preferred stimuli) and pressure microswitches to choose among them. Intervention data of Study I showed that the participants acquired relatively high levels of microswitch responding (thus engaging widely with preferred environmental stimuli) and kept that responding consistent except for one case. Intervention data of Study II showed that the participants were active in choosing among preferred stimuli and positive caregivers' procedures, but generally abstained from non-preferred stimuli. The results were discussed in terms of the successful use of fairly new/infrequent microswitch-response arrangements (Study I) and the profitable inclusion of functional caregiver's procedures among the options available to choice (Study II).

Technology-based intervention to help persons with minimally conscious state and pervasive motor disabilities perform environmentally relevant adaptive behavior

Persons with a diagnosis of minimally conscious state and pervasive motor disabilities tend to be passive and isolated. A way to help them improve their adaptive behavior (relate to their environment) involves the use of intervention packages combining assistive technology with motivational strategies. The types of assistive technology included in those packages may consist of (a) microswitches allowing direct access to environmental stimuli, (b) combinations of microswitches and voice output communication devices (VOCAs) allowing stimulus access and calls for caregivers' attention, respectively, and (c) computer presentations of stimulus options and microswitches allowing choice among those options and access to them.