Virtual reality (VR) in the context of mental health is emerging with several examples, such as relaxation through biofeedback, exposure therapy, pain management, and addiction coping. Furthermore, sensors ofer a way to objectively assess the children's response to therapy, which can be associated with self-report questionnaires to give even more accurate feedback to the therapist. The goal of this paper is to shine a light on the current state-of-the-art and reflect on the opportunities and challenges of VR to improve mental health-related outcomes in children and adolescents. We conducted a narrative review focusing on both VR exposure for children and adolescents and sensors' use for VR exposure. Virtual reality exposure therapy (VRET) seems to have similar results to other forms of exposure. Additionally, sensors managed to obtain an objective picture, which allows the therapist to get some objective measures during therapy. Although cybersickness seems to not be a major side efect in children, other limitations such as fear of the equipment and lack of adaptability were identified. Notwithstanding these limitations, VRET is a well-founded alternative to in vivo and imaginal exposures to treat anxiety disorders in children, when associated with physiological sensors and self-report questionnaires. Due to its advantages, it is paramount to continue to perform more studies using this technology, further improving its efectiveness and availability.
1. Introduction Exposure therapy is a therapeutic approach where the patient is gradually exposed to traumatic stimuli, which aims to help patients to cope with feelings of fear/anxiety and decrease avoidance. This type of exposure has been used in several anxiety disorders, such as phobias [1], Social Anxiety [2], Posttraumatic Stress Disorder (PTSD) [3], Obsessive-compulsive Disorder (OCD) [4], and Generalized Anxiety Disorder [5]. There are several approaches to exposure therapy, such as imaginal and virtual reality, but the most well-known and well-founded is in vivo exposure therapy. In this approach, the patient experiences (i.e., is exposed to) the traumatic stimulus in the real world. This methodology raises several practical and ethical issues. For instance, for fear of flying (i.e., aerophobia), one would take the patient to an airport and several flights, risking breaking confidentiality and high costs [6].
Virtual Environments (VE) are built using software and aim to recreate the real world. These environments immerse users in realistic settings, allowing them to engage intuitively and intimately with the digital environment [7]. Over the years, further improvements to their realism, general display, and tracking technologies advancements, opened the possibility for its use in health, accompanied by big displays or Head-Mounted Displays (HMD).
This technology has already been used in a plethora of diferent approaches in the context of health, such as reducing pain in children during painful procedures [8], calming patients through biofeedback [9], and coping with anxiety disorders. However, continued eforts are still needed to improve VRET when applied to children and adolescent mental healthcare.
Virtual Reality Exposure Therapy (VRET) has been proven to be efective in the treatment of anxiety disorders in children and adolescents. Studies showed that almost all children prefer VRET compared to in vivo [10].
This is an important finding since most patients with anxiety disorders are reluctant to find treatment due to avoidance. A major limitation of VR-based therapies is cybersickness; however, children seem to be not particularly afected by it [ 11], being more susceptible to other complications such as fear of getting stuck inside the VR [12] and fear of losing control [13].
Therapists assess the efectiveness of therapy by using well-established self-report questionnaires. However, self-report questionnaires possess some limitations, such as low reliability in young children [14], and being timeconsuming (i.e., requiring time to answer), thus eliminating feasibility while exposure therapy takes place.
Physiological sensors ofer an opportunity for improvement by objectively evaluating how the patient is doing.
Although the available sensors still present some limitations (e.g., bulkiness towards children, discomfort), the data collected enable therapists to develop (in a more tient feels and perceives his/her mental health, which is dynamic way) new therapeutic strategies based on the probably (one of) the most significant metrics in therapy. signals collected. Although having its benefits and potentially overcom
Given the exponential use of virtual reality (VR) as a ing some of the limitations that traditional approaches to therapeutic tool to improve mental health-related out- exposure therapy in children and adolescents have, one comes, this paper focuses on the current state-of-the-art of the disadvantages of VRET is the danger of cybersickof VR technology and physiological sensors in the con- ness [15]. Cybersickness can often be caused by the lack text of exposure therapy in children and adolescents for of consistency of the patient’s head movement in real anxiety disorders. Furthermore, we aim to identify cur- life and the virtual environment (high latency), lowering rent challenges and opportunities in using VRET to treat the efects of the therapy depending on the severity of anxiety disorders in children and adolescents. the symptoms. These can range from nausea, eyestrain, headache, and dizziness, among others, depending on the patient and their age and gender. However, children 2. Methods and adolescents are less likely to develop cybersickness or simulation sickness, as most studies report none or We conducted a narrative review in Google Scholar elec- minimal symptoms across patients [11]. tronic database, using keywords, such as “virtual reality Despite cybersickness not being a significant limitation exposure for children”, “virtual reality exposure for ado- due to the targeted groups, some shortcomings still arise. lescents”, “virtual reality exposure anxiety disorders”, Some younger children reported fear of “getting stuck and “sensors for virtual reality exposure” to find rele- in the headset and of seeing something scary like in a vant papers. The bibliography found showed a lack of horror movie” [12], with some children even refusing to studies performed with children in this context, so we wear the headset turned of due to fear of losing control extended the search of information to papers regarding over the situation [13]. Even though these concerns are adults aiming to find relevant information that could be valid and important, some solutions can be applied so extrapolated to children. Overall, 43 papers were identi- that the patient feels more at ease. An important factor ifed as relevant based on title and abstract content and to mediate this is increasing the level of control the child included in this review. After full-text analysis, some perceives feels they have over the situation [16]; the more were excluded due to not being relevant to children, be- in control the patient feels of the situation, the better it ing reviews of already known papers, or lack of a future will adapt and handle the treatment; simple measures direction. such as letting the children choose the movie they will see [13], increase the sense of control the patient has, 3. Virtual Reality Exposure with thus promoting a faster adaptation to the treatment.
Another limitation of working with VR headsets and Sensors physiological sensors is that these are rarely made with children in mind. Moreover, the headset can feel bulky to the patient [11], or even just the sensors, which can make the child anxious or uncomfortable during therapy.
Furthermore, children and adolescents usually adapt and even enjoy being exposed to virtual environments, often developing a high SoP further improving the exposure and potentially the efectiveness of the treatment.
However. we did not find any specific ethical challenges (i.e., the therapist being removed from the equation due to not being in the virtual environment with their patient) or reflections towards these.
Virtual Reality Exposure Therapy (VRET) alongside the use of Sensors comes to try to overcome some of the issues presented above. By using virtual reality in virtual environments and navigating through them using HMDs, the patient can experience an enhanced Sense of Presence (SoP), which has been associated with improved outcomes in VRET. Moreover, this can be done in the therapist’s ofice at a relatively low cost, tackling two of the limitations associated with in vivo exposure (possible high costs and break of confidentiality). Furthermore, it also gives the therapist more control of the environment and the therapeutic session, allowing for a more tailored and detailed exposure for each patient. With the use of 4. Research Opportunities sensors, the therapist can see how the patient is doing in real-time, allowing for the environment to be changed The literature shows that the use of VRET with sensors in forthwith, thus improving the experience and, therefore, children is safer and more approachable when compared the efectiveness of the exposure. Nonetheless, there is to its counterparts (in vivo and imaginal). Moreover, still the need to analyze the correlations/associations be- most patients preferred VRET over in vivo exposure [10]. tween these measures and self-report questionnaires, as Regarding sensors, their use is good to assess how the the former measures are more indicative of how the pa- patient is doing physically at any given moment, which informs the therapist regarding how stimuli should be Hardware adapted to children. Most hardware used manipulated to increase therapy eficacy. In addition, sen- in studies was not made for children. Moreover, Headsors can be used to assess the efectiveness of the treat- Mounted Displays can often feel bulky, and the interfaces ment, especially if used complementary to self-report are sometimes hard to understand [11], which can afect questionnaires. However, there is still a lack of studies the efectiveness of the therapy. Sensors can also cause with bigger test groups and studies focused on children discomfort and anxiety when too invasive and big. A and adolescents. Therefore, we outline a set of open re- possible solution for this problem would be to adapt the search avenues in this field that would be interesting to technology to the children, and not the children to the pursue to further develop this therapeutic approach. technology. This would also work well to increase SoP,
Explore how to reduce dropout rates with VRET. which is shown to be important for the efectiveness of Dropout rates in exposure therapy, albeit in vivo, imagi- the therapy [19]. The creation of smaller and more childnal, or virtual reality, are a major challenge. Most of the adapted VR-Headsets and sensors, specifically designed studies included in the present review do not explicitly for VRET in children and adolescents, might help overreport the reasons for the number of dropouts observed come this problem. Hopefully, this can eliminate some [5]. Although the available literature shows that VRET barriers that hamper children’s adoption of VRET. presents similar dropout rates as in vivo exposure ther- Improve self-report questionnaires for children. apy [5], it also ofers a golden window to understand Clinicians use several well-established and childrenwhy patients quit interventions. By using sensors, one designed self-reports such as Clinician-Administered can assess how the patient is doing physically at a given PTSD Scale for DSM-5 (CAPS-5), Screen for Child Anxpoint and identify dropout-risky moments, which is the iety Related Emotional Disorders (SCARED), and the key to finding solutions to minimize the patient wanting Spence Children’s Anxiety Scale (SCAS) [20]. Although to quit treatment. these and others exist, there is always an opportunity
Self-report questionnaires and sensors hand-to- for improvement in this field, as some of these questionhand. Physiological sensors can track signals such as naires can be outdated, not reflecting the daily constraints Heart and Respiration rates [4], Galvanic Skin Response and sources of anxiety that were nonexistent maybe 15 [17], and diaphragm expansions [18]. Although sensors years ago, such as social media exposure and a decrease ofer an objective measure towards the physical well- in socialization skills. We suggest further research rebeing of a patient, there is the possibility that an im- garding self-report questionnaires by working directly provement in physiological measures might not reflect with children and adolescents to explore how anxiety an improvement in a patient’s self-perceived mental state is experienced and what factors might trigger or aggra(e.g., patients do not perceive improvements in their cop- vate it by using a combination of up-to-date self-reported ing skills) [13]. On the other hand, self-report question- questionnaires and sensors to consolidate results. naires are more accurate regarding how the patient feels, Perform more studies with VRET and OCD in but they require a certain level of psychological matu- children. Although VRET in children has shown enrity and vocabulary that young children might lack [14]. couraging results, there is still a lack of research on other Furthermore, questionnaires’ results are not obtained mental health disorders, such as obsessive-compulsive instantaneously, as the patient needs to take time to an- disorder. This is mostly because this disorder is unpreswer the questions thoughtfully. Here, the creation of a dictable, and presents itself in various ways, making it system that combines these two types of measures might dificult to treat. The five most common types of OCD are help to mitigate some of the problems raised when sen- organization, contamination, intrusive thoughts, ruminasors and self-report questionnaires are used separately. tions, and checking. Usually, the obsessive and ritualistic By combining them, the therapist could correlate the behaviors (symptoms), can arise from an attempt by the physiological sensors’ data with the results of self-report patient to get more control of the surrounding environquestionnaires to have a more accurate evaluation of ment and, therefore, lower their anxiety levels. In the the patient’s progress, regardless of their age or lack of review conducted, we found some evidence validating vocabulary skills. the use of VRET for contamination-type symptoms [4].
Make the therapy well-suited for each patient. Focusing on one type of OCD symptom can make it easBy gathering data on how the patient is performing and ier to develop working exposure to mitigate some of the feeling in real time, sensors open another window of symptoms and dificulties patients live with, serving as a opportunity: changing the VR experience in real-time. By stepping stone to other types of this disorder. catering the therapy and changing it in real time, focusing Give the patient more control and autonomy over on data collected from each patient, the therapist can their therapy. Some children reported being afraid of perform a more tailored exposure therapy, which may losing control of the situation while engaged in the virincrease the SoP and, therefore, the efectiveness of the tual environment [13]. Control over the situation also treatment. improves SoP and makes the patient more engaged in the virtual environment, working as a catalyst to up the oficial Publication of The International society for efectiveness of the exposure. VRET opens the possibility Traumatic stress studies 21 (2008) 209–213. for a more nuanced experience regarding control, as it [4] A. J. Cullen, N. L. Dowling, R. Segrave, A. Carter, lets the virtual environment be completely changed to M. Yücel, Exposure therapy in a virtual environthe patient’s needs and/or actions. ment: Validation in obsessive compulsive disorder, Journal of Anxiety Disorders 80 (2021) 102404. [5] D. Opriş, S. Pintea, A. García-Palacios, C. Botella, 5. Conclusion Ş. Szamosközi, D. David, Virtual reality exposure therapy in anxiety disorders: a quantitative metaAs anxiety disorders in children become increasingly analysis, Depression and anxiety 29 (2012) 85–93. common, especially after the COVID-19 pandemic [21], it [6] B. O. Rothbaum, P. Anderson, E. Zimand, L. Hodges, is imperative that alternatives made for children become D. Lang, J. Wilson, Virtual reality exposure thermore available. apy and standard (in vivo) exposure therapy in the
By conducting this narrative review of the literature, treatment of fear of flying, Behavior therapy 37 it was possible to identify that VRET combined with (2006) 80–90. sensors is a promising approach for the development of [7] K. Stanney, J. Cohn, Virtual environments (2009). efective and accessible approaches to exposure therapy. [8] S. Q. Scapin, M. E. Echevarría-Guanilo, P. R. B. FuVRET allows the recreation of more intense scenarios culo, J. C. Martins, M. d. V. Barbosa, M. J. L. Pereima, that one would not typically find in in vivo. Moreover, Use of virtual reality for treating burned children, VRET is a less “invasive” option than traditional exposure Revista brasileira de enfermagem 70 (2017) 1291– therapy approaches, enabling the therapist to focus on 1295. the patient while having more control over the session. [9] S. Gradl, M. Wirth, T. Zillig, B. M. Eskofier, ViWhen sensors are combined with the VRET, the therapist sualization of heart activity in virtual reality: A can take some measures quickly, and change the virtual biofeedback application using wearable sensors, in: reality environment/experience in real time if needed. 2018 IEEE 15th international conference on wearFurthermore, the combination of sensors and self-report able and implantable body sensor networks (BSN), questionnaires seems a promising approach to further IEEE, 2018, pp. 152–155. knowledge on the efectiveness of VRET. [10] F. Dehghan, R. Jalali, H. Bashiri, The efect of vir
Performing more studies regarding VRET is of seminal tual reality technology on preoperative anxiety in importance, as it will make treatment more accessible, children: a solomon four-group randomized clinical afordable, and less frightening for patients (including trial, Perioperative Medicine 8 (2019) 1–7. adults). [11] M. Tennant, N. Anderson, G. J. Youssef, L. McMillan, R. Thorson, G. Wheeler, M. C. McCarthy, Efects Acknowledgments of immersive virtual reality exposure in preparing pediatric oncology patients for radiation therapy, This work was partially supported by FCT through Technical Innovations & Patient Support in RadiaLASIGE funding (ref. UIDB/ 00408/2020 and ref. tion Oncology 19 (2021) 18–25. UIDP/00408/2020) and the EU H2020 WideHealth project [12] O. D. Kothgassner, A. Felnhofer, Lack of research (grant agreement No 952279). on eficacy of virtual reality exposure therapy (vret) for anxiety disorders in children and adolescents: A systematic review, neuropsychiatrie 35 (2021) References 68–75.
[13] B. Buldur, M. Candan, Does virtual reality afect [1] A. Garcia-Palacios, H. G. Hofman, S. Kwong See, children’s dental anxiety, pain, and behaviour? a A. Tsai, C. Botella, Redefining therapeutic success randomised, placebo-controlled, cross-over trial, with virtual reality exposure therapy, CyberPsy- Pesquisa Brasileira em Odontopediatria e Clínica chology & behavior 4 (2001) 341–348. Integrada 21 (2020). [2] P. Anderson, B. O. Rothbaum, L. F. Hodges, Virtual [14] R. S. McGinnis, E. W. McGinnis, J. Hruschak, reality exposure in the treatment of social anxiety, N. L. Lopez-Duran, K. Fitzgerald, K. L. Rosenblum, Cognitive and Behavioral Practice 10 (2003) 240– M. Muzik, Rapid anxiety and depression diagno247. sis in young children enabled by wearable sensors [3] M. Gerardi, B. O. Rothbaum, K. Ressler, M. Heekin, and machine learning, in: 2018 40th Annual InA. Rizzo, Virtual reality exposure therapy using a ternational Conference of the IEEE Engineering in virtual iraq: case report, Journal of Traumatic stress: Medicine and Biology Society (EMBC), IEEE, 2018, pp. 3983–3986. [15] Y. Shiban, Virtuelle expositionstherapie bei angst
störungen., Der Nervenarzt (2018). [16] N. Ahmadpour, M. Keep, A. Janssen, A. S. Rouf,
M. Marthick, et al., Design strategies for virtual reality interventions for managing pain and anxiety in children and adolescents: scoping review, JMIR serious games 8 (2020) e14565. [17] A. C. Katz, A. M. Norr, B. Buck, E. Fantelli,
A. Edwards-Stewart, P. Koenen-Woods, K. Zetocha, D. J. Smolenski, K. Holloway, B. O. Rothbaum, et al., Changes in physiological reactivity in response to the trauma memory during prolonged exposure and virtual reality exposure therapy for posttraumatic stress disorder., Psychological Trauma: Theory,
Research, Practice, and Policy 12 (2020) 756. [18] M. Van Rooij, A. Lobel, O. Harris, N. Smit, I. Granic,
Deep: A biofeedback virtual reality game for children at-risk for anxiety, in: Proceedings of the 2016 CHI conference extended abstracts on human factors in computing systems, 2016, pp. 1989–1997. [19] B. O. Rothbaum, L. F. Hodges, The use of virtual reality exposure in the treatment of anxiety disorders,
Behavior Modification 23 (1999) 507–525. [20] P. Muris, H. Schmidt, H. Merckelbach, Correlations among two self-report questionnaires for measuring dsm-defined anxiety disorder symptoms in children: The screen for child anxiety related emotional disorders and the spence children’s anxiety scale, Personality and Individual Diferences 28 (2000) 333–346. [21] L. A. Lebrun-Harris, R. M. Ghandour, M. D. Kogan,
M. D. Warren, Five-year trends in us children’s health and well-being, 2016-2020, JAMA pediatrics 176 (2022) e220056–e220056.