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Virtual Reality as a Technological-Aided Solution to Support Communication in Persons With Neurodegenerative Diseases and Acquired Brain Injury During COVID-19 Pandemic

The COVID-19 poses an ongoing threat to lives around the world and challenges the existing public health and medical service delivery. The lockdown or quarantine measures adopted to prevent the spread of COVID-19 has caused the interruption in ongoing care and access to medical care including to patients with existing neurological conditions. Besides the passivity, isolation, and withdrawal, patients with neurodegenerative diseases experience difficulties in communication due to a limited access to leisure opportunities and interaction with friends and relatives. The communication difficulties may exacerbate the burden on the caregivers. Therefore, assistive-technologies may be a useful strategy in mitigating challenges associated with remote communication. The current paper presents an overview of the use of assistive technologies using virtual reality and virtual body ownership in providing communication opportunities to isolated patients, during COVID-19, with neurological diseases and moderate-to-severe communication difficulties. We postulate that the assistive technologies-based intervention may improve social interactions in patients with neurodegenerative diseases and acquired brain injury-thereby reducing isolation and improving their quality of life and mental well-being.


INTRODUCTION
Persons with neurodegenerative diseases and acquired brain injuries may fail while dealing with everyday life environmental requests. Their independence, social interactions, communication skills, and functional activities may be seriously hampered with deleterious effects on their quality of life (1)(2)(3). Isolation, passivity, and detachment may be observed with negative outcomes on caregivers and families' burden (4)(5)(6).
Both intellectual and motor impairments may emerge with a significant reduction of an overall individual's functioning (7,8). To be effective, a rehabilitative intervention should be implemented early regarding brain damage and should be intensive and assiduously prolonged over the time. Moreover, to be consolidated and generalized, the learning process should be pursued across settings (9,10). Unfortunately, COVID-19 pandemic relevantly impeded the implementation and the realization of those conditions (11,12). In fact, by December 24, 2020, over 72 million of cases have been documented worldwide, with almost 1.7 million of deaths (13,14). Quarantine and social distancing interrupted public health services and regular medical care delivery (15). Public health preventions have centered around socialdistancing, masks, and hand-washing strategies. Patients with chronic neurodegenerative diseases (e.g., Alzheimer, Parkinson, amyotrophic lateral sclerosis), demyelinating diseases as multiple sclerosis, and persons with acquired brain injuries (e.g., stroke, post-coma) have been impacted by lockdowns-making them vulnerable during the COVID-19 (16). In order to deal with these issues, one may envisage assistive technology (AT)-based strategies (17,18).
AT options are broadly recognized as crucial means of support for individuals with neurodegenerative diseases and acquired brain injuries and multiple disabilities (19). Thus, AT-based programs are commonly planned to favorably fill the gap between behavioral/cognitive skills and environmental requests (20). That is, an AT setup is conceived to build functional bridges between users, environment, and technology. Essentially, it ensures that a helpful interaction (i.e., purposeful behavior and goal-oriented) is achieved for persons with extensive motor delays (21). That interaction is critical to enhancing personal fulfillment, social image, active role, satisfaction, and improving quality of life accordingly (22). Among different targeted areas, communication and leisure opportunities have been promoted (23)(24)(25). Scopus database emphasizes different empirical contributions which demonstrate the relevance and the beneficial effects on practical daily issues (e.g., communication, leisure, internet access) of technology-based programs in individuals with neurodegenerative diseases and acquired brain injuries (26)(27)(28)(29)(30)(31)(32).
At present, striking changes for public health and medical delivery services have been determined by COVID-19, including the need to find alternative solutions to take action against the substantial interruption of the regular medical care assistance and to social distance limitations forced by this pandemic (33)(34)(35)(36). The main goal of this article is to propose a perspective on a new AT-based approach in using VR and virtual body ownership illusions to enable the communication of the patients with neurological diseases and severe-to-profound disabilities in case of isolation inside the hospital or in his/her home during this pandemic situation. In this context, current evidencebased recommendations on the use of AT-based strategies, including virtual reality (VR), as technological-aided solutions to support communication and leisure in neurological disorders, will be explored.

COMMUNICATION AND LEISURE IN NEUROLOGICAL DISORDERS
Failure to positively engage in communication and leisure activities includes the incapacity to handle social interactions independently and profitably. For instance, individuals with neurodegenerative diseases and acquired brain injuries and multiple disabilities may be unable to undertake and pursue leisure activities autonomously, that is, they remain dependent on both families and caregivers. Additionally, people with neurological impairments may be unable to adequately communicate their needs or favorably make requests and choose desired items. Moreover, people with neurological impairments may face difficulties in communicating with distant partners (37,46,47). Technological-aided setups may be viewed as helpful supports focused on filling the existing gap between the actual individual's skills and the skill level necessary to achieve functional objectives. Accordingly, AT-based devices, setups, and tools should be rigorously customized in terms of (a) personal skills and (b) meaningful goals to be useful (48). For instance, whenever the individual has extensive motor disorders and lack of speech but is estimated within a normal range of intellectual functioning (e.g., multiple sclerosis), one may design technological aids aimed at helping the patients perform different adaptive responses. Practically, with the AT-based intervention, persons with neurodegenerative diseases and acquired brain injuries and significant impairments may be helped (a) to make small adaptive responses available in their behavioral repertoire and (b) to use adaptive responses to achieve functional tasks and/or pursue meaningful purposes (49). Communication or leisure opportunities or their combination could be embedded in a rehabilitation program using AT (39,40,50). Moreover, communication with distant partners through short text messages, telephone calls, or video-calls may be implemented to promote social interactions (51,52). For instance, (53) the newly developed high-sensitivity mechanical switch for augmentative and alternative communication access in people with amyotrophic lateral sclerosis, namely the Lever Magnetic-spring Mechanical Switch (i.e., LeMMS). Results of the validation study evidenced that all the participants were capable to operate the LeMMS, which could help these patients to communicate even in an advanced stage of the disease.  anxiety and depression levels among individuals with multiple sclerosis, Parkinson's disease, and acquired brain injuries (55). Across neurological diseases, poor mental health is linked to poor quality of life, greater disability, poor prognosis and disease improvement, poor benefits after intervention (56).
Accordingly, some studies have demonstrated that improving social communication in patients presenting neurodegenerative diseases and acquired brain injuries may improve their quality of life (57). Indeed, the relationship between verbal communication ability and quality of life has been shown. In detail, initial speech impairment in patients with neurodegenerative diseases and acquired brain injuries have a strong impact on their quality of life (58). Internet connections are crucial to ensure people with timely social interactions, general public awareness, enhanced health conditions, specific knowledge on otherwise less-known neurological diseases, and health-related coping (59). Patients with neurological impairments can easily find numerous opportunities for peer social connections, learning, and leisure options (60). Furthermore, neurologists can easily manage usergenerated data to satisfactory have an exhaustive representation of patients' needs and carry out epidemiological investigations (61). For example, a recent study (60) explored when and how technology could help interactions among patients with dementia and their caregivers. Three dyads patient-caregiver living in their homes were equipped with tablet computers and webbased applications and researchers analyzed their interactions. The study outlined benefits in terms of dyad interaction derived from the use of technology, suggesting the importance of an adequate provision of technology-based equipment for individuals with dementia.
Telerehabilitation (TR) offers a medium to deliver rehabilitation services and manage patients remotely using technology-based information and communication (61,62). The adopted technologies may broadly include emails, data transmissions through videos and/or photos sent by the health provider or the user or both (63). Additionally, tablets and computers, internet-based media or programs, video conferencing, smartphones, and webinars are usually embedded (64). Typically, TR may be adopted as synchronous (i.e., the health provider and user are simultaneously connected) or as asynchronous (i.e., the health provider and user are not simultaneously connected but connected through stored data and virtual technologies or electronic communication) (41,65). Currently, one of the newest technologies used to engage patients and caregivers in the TR training is VR systems (65,66).

TELEPRESENCE AND VIRTUAL REALITY
At the end of the last century, VR constitutes the evolution of the old communication interfaces such as telephone, computer, and television toward the emergence of the integration of different data coming from different modalities (67). According to this, Biocca and Levy (68) defined VR as a communication system instead of a piece of technology (69). Then, VR is a communication interface connecting: (1) physical media, (2) codes, (3) information, and (4) sensorimotor channels (69). A main characteristic of VR is that allows the full immersion of the human sensorimotor channels into a vivid and realistic communication experience (68). In fact, VR is a successor of internet-based communication (70). Essentially, VR represents a technology through which it is possible to simulate existing experiences into a fake immersive virtual environment (71). Immersion is related to the extent to which the VR systems can deliver an inclusive, extensive, surrounding, and vivid illusion of reality to the participant's sensory senses. Then, immersion corresponds to the objective and quantifiable description of what the technology can provide (72). For instance, some studies demonstrated the use of VR systems, such as wearable headsets and 3-D smart televisions, to provide enjoyable, leisurely activities, with benefits in terms of quality of life, psychological well-being, and facilitated social interactions in patients with cognitive impairment (73). One example is a VR intervention using a virtual environment displayed on two large screens with head-mounted 3-D glasses and body-tracking sensors to promote engagement in patients with Mild Cognitive Impairment (74).
Another main feature of the VR system is the capability to induce a sense of "presence" into the virtual environment, which corresponds to the psychological perception of being in the virtual environment (72,75). However, as described by Schroeder in 1996: "The notion of communications technology normally implies two or more people are involved and the emphasis is placed on the messages that pass between them" (p. 146) (76). In this regard, VR allows the possibility to interact with the immersive virtual environment and different virtual characters or avatars (77). Through VR, it is also possible to induce the sense of co-presence, that is the sense of being together in a shared space, combining significant characteristics of being both physically and socially present (78). According to this, it has been argued that the validity of the telepresence depends on the capacity to produce a context in which social actors, or social avatars in the case of VR, may communicate and cooperate between them (79)(80)(81). In line with this definition of telepresence, a large number of investigations induced telepresence within a virtual environment by means of virtual body ownership illusions (82)(83)(84). In these experimental studies, the researchers induced the illusion, by using synchronous visuo-tactile stimulation of being in the embodied virtual body instead than in the real one, inducing the sense of telepresence among the participants (82)(83)(84). Due to the possibility of moving subjects from one place to another when using VR systems, telepresence results as a promising strategy to facilitate communication with patients and their relatives when they are at home (45).

NEW COMMUNICATION TECHNOLOGIES: VIRTUAL REALITY AS A COMMUNICATION TOOL IN CLINICAL POPULATIONS
Based on the above-commented VR systems components, a recent study investigated how VR may contribute to older adult well-being by facilitating greater social VR participation (42,85). In detail, in the study from Baker and colleagues, the authors conducted three workshops in which 25 older adults aged from 70 to 81 used VR as a medium for communicating with other participants (42). Older adults had to create embodied virtual avatars controlled through natural gestures and subsequently successfully and effectively used these avatars in two social VR prototypes from a third-or a first-person perspective. In this line, others used VR as a communication tool allowing medical staff to virtually interact with a virtual avatar assistant to assess and treat a virtual avatar victim presenting clinical complications (86). Additionally, virtual medical interaction with the patients through virtual avatars and telepresence has also been proposed (45,(87)(88)(89). In detail, Perez-Marcos and colleagues presented an innovative VR set-up that allows remote interaction and rehabilitation, including both the patient and doctor body projection into virtual bodies in a fully immersive environment and the physical embodiment at the remote place (45).
According to these promising studies, here we propose a VR intervention to foster and facilitate social interactions with both the clinicians and relatives with virtual avatars and telepresence in patients with neurological disorders. Such an intervention could be used when patients are isolated due to their clinical condition or to the social distance limitations forced by the COVID-19 pandemic situation. The proposed intervention aims to improve the patient's well-being avoiding his/her isolation. Specifically, it is a new VR social intervention by means of full-body ownership illusions observed from a first-person perspective and delivered through a head-mounted display and the activation of a social VR application. The effectiveness of the VR social application for enhancing social interactions through virtual avatars has been previously shown in healthy individuals (90). The intervention aims to reproduce the patients' and their relatives' body representation within the same VR environment, that is a virtual living room. In this regard, the virtual avatars' anthropomorphism characteristics are important to further enhance the sense of ownership and increase the sense of presence in interaction with other virtual avatars (42,43,91). This intervention is composed of five different phases: (1) the creation of the virtual avatars by scanning patients' and relatives' real bodies as in the study conducted by Osimo and co-authors or in the study by Orts-Escolano and colleagues (44,92); (2) the integration of such virtual avatars into the VR social application; (3) delivery and teaching to use the VR social application and the head-mounted display; (4) the creation of daily social VR appointments to meet and interact with the patient's relatives during isolation or hospitalization period; and (5) the creation of weekly social VR appointments between relatives and medical staff for an updating about patient's medical condition.
The proposed intervention may represent a solution to the current worldwide situation caused by the COVID-19 pandemic, which requires suitable and effective technology-based approaches. Many recommendations are indeed proliferating about the need of alternative strategies for delivering health care services in this contingency (33,34,93). If some months ago the focus was mainly on the treatment of COVID-19 patients (94)(95)(96)(97)(98)(99), now a days we are assisting in a growing interest for alternative ways to support the process of care of non-COVID conditions, including patients with neurodegenerative diseases and acquired brain injuries (100)(101)(102). For instance, there are many evidences about the use of telemedicine-understood as an interface in a virtual patient-clinician relationship to provide primary and secondary care (62, 99-102)-and virtual reality for remote delivery of cognitive rehabilitation in various settings of neurological care (103)(104)(105). In this frame, we propose a VR-based intervention aimed to support another critical aspect of individual's functioning that is communication, in persons with neurodegenerative diseases and acquired brain injury during COVID-19 pandemic. Thus, by using an ATimplemented strategy such as VR interventions, patients with neurodegenerative diseases may be enabled to communicate his/her needs, feelings, and thoughts to their relatives or medical staff during the hospitalization or isolation period. Accordingly, it may be fostered with positive outcomes on his/her health conditions, with a meaningful reduction of the anxiety and/or depression levels, and with beneficial effects in terms of quality of life (106,107). Therefore, the caregivers, families, and health care systems may find a significant burden reduction (108,109). In conclusion, through this VR intervention for communication, the patients may (a) communicate their needs, (b) independently access leisure options (e.g., positive stimulation, favorite videos, amusing songs), and (c) be connected with distant relatives. Then, patients will be more engaged in communication, and with a purposeful behavior (110,111). In this regard, the use of new technologies for fostering engagement in patients with neurodegenerative disorders has been demonstrated (65,112,113).

CONCLUDING REMARKS
The level of independence, social interactions, communication skills, and functional activities may be seriously hampered in patients with neurodegenerative diseases with deleterious effects on their quality of life (1-3). The isolation because of the COVID-19 pandemic situation may enhance such negative aspects with consequences on their quality of life (30,114). To avoid that, some studies propose VR as a technologically-aided solution for clinical populations (99,107,115). However, most of these studies are focused on using VR to continue with the treatments and rehabilitation routines of the patients in case of isolation or social distancing. Depending on their level of functioning, persons with neurodegenerative diseases may be exposed to different aided-technological solutions to enhance communication skills. For example, individuals with extensive motor disabilities and moderate-to-severe intellectual disabilities may be involved in social interactions through vocal output communication aid (VOCA) or speech generating devices (SGD). Else, one may envisage hierarchical computerized systems with adapted software enabling patients with neurodegenerative diseases to request and choice desired items and/or communicate their needs. Otherwise, for individuals estimated with an intellectual normal functioning and extensive motor impairments, the independent access to the literacy through computerized systems and keyboard emulators may be proposed. Moreover, during lockdown or quarantine imposed due to an infectious disease outbreak, one may consider the communication with a distant partner through technology-aided options including a smartphone and a global system for mobile communications (GSM) system (116,117). Here we proposed a VR-AT solution to enable the communication among patients with neurodegenerative diseases or acquired brain injury, relatives, and medical staff during the COVID-19 pandemic situation. We hypothesized that this intervention may improve the patient's social interactions enhancing their quality of life and mental well-being, avoiding isolation and negative psychological and cognitive effects.

DATA AVAILABILITY STATEMENT
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

AUTHOR CONTRIBUTIONS
FS, MM-G, and SBo have conceived the work. All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.