Virtual reality technology in the treatment of anxiety – progress and future challenges

KEYWORDS:

• Virtual reality
• anxiety disorder
• clinical trials
• simple phobia
• social anxiety disorder
• post-traumatic stress disorder
• avatar

1. Background

Virtual reality (VR) applications present visual and auditory material (sometimes also tactile using joysticks or sensory gloves) via a headset which creates a 3-D immersive, real-like experience, achieved through simulated stereoscopy [1]. VR is increasingly affordable and commonly used in gaming, as well as other sectors including education, health, training, simulations, and retail and marketing [2,3].

Anxiety disorders are common across the globe including in low- and middle-income countries [4]. Treatment guidelines for anxiety disorders generally recommend psychological treatment as first line, with the addition of medications in some cases [5,6]. However, the availability, particularly of psychological treatment, is limited even in high-income countries [7]. This has led to an emphasis on online treatment packages in some guidelines [8].

VR technology has huge potential in many areas of health. In anxiety disorders, there has been a recent acceleration of research which has been well summarized by reviews and meta-analyses [2]. The aim of this editorial is not to review in detail the literature to date but to discuss the clinical issues which may be addressed by VR technology and to consider some of the clinical and research challenges in this field for the future.

2. VR for phobias

Phobias involve an irrational and uncontrollable fear of certain objects or situations. They are classified as ‘simple’ in which the feared stimulus is a single object or class of objects (e.g. spiders or dogs) or ‘complex’ in which the situation involved is not a simple object – as in the case of social anxiety disorder and agoraphobia. Exposure to the feared stimulus results in severe and unpleasant anxiety resulting in increased or maintained fear of the stimulus. If that anxiety can be attenuated during and after exposure, then the phobia can gradually be extinguished. Most studies to date have involved the use of VR to aid the process of graded exposure. In graded exposure, patients are exposed to increasing ‘levels’ of the phobic stimulus. At each level of exposure, anxiety management techniques (often based on cognitive behavioral therapy) are practiced to ensure that the anxiety induced is reduced to a manageable level. This therefore does not reinforce the phobia – and ultimately the phobia will be, at least partially, extinguished. One of the practical challenges in therapy is to produce a series of graded exposures, and this can require a high level of commitment and time, both from the patient and the therapist. This is probably one of the factors which results in exposure-based techniques being used much less commonly than might be expected [9]. There is potential for VR to improve this situation, since it allows the use of film clips or artificially produced (animated) scenarios transposed into a VR environment – and therefore the much easier construction of a hierarchy of exposures which ‘feel real’ and are controllable. Exposure is also much more easily repeated. VR scenarios are, of course, more controllable than real-life exposures – as Garcia-Palacios [10] note, ‘unlike a real spider, virtual spiders obey commands.’ There is evidence that therapy supported by VR is more acceptable than in-vivo exposure [11].

One of the important variables in this process is the degree to which VR can reduce the need for therapist input. Studies conducted to date, in simple phobic disorders, have varied from those which have been conducted in research centers, with in-person therapist support [10], to those which use phone apps with minimal in-person support in any part of the therapy [12]. Both have been found to be more effective than comparison treatments – usually wait list control [1]. Side effects, nausea being the most common, tend to be relatively infrequent. Practically, a stepped care approach may be possible, starting with a trial of VR without therapist support but with the option of engaging therapist support in the case of issues with the therapy or inadequate response.

An important issue for any new treatment is its availability in remote area and in low- and middle-income countries. While headsets are currently expensive, smartphones that can deliver the software packages are common and now cheap in LMICs. VR headsets are also likely to become significantly cheaper as their use for gaming increases.

Studies have also begun to examine the use of VR for social anxiety disorder and agoraphobia with promising preliminary results [1]. How the use of VR is supported in these more complex disorders is of course important. For less complex situations, it could be argued that even a low level of response to ‘self-guided’ VR therapy may reduce waiting lists. In the case of social anxiety disorder, the solitary nature of VR therapy (apart from the presence of ‘virtual people’) may be an advantage, at least in the early stages of therapy. However, as complexity and degree of co-morbidity increases, face-to-face therapist support may improve outcomes. In this situation, evidence suggests that augmenting standard (CBT) therapy with visual reality exposure does offer an advantage over CBT alone [13].

3. VR for Post-traumatic stress disorder (PTSD)

PTSD involves, among other symptoms, the reexperiencing of traumatic events, often in memories or ‘flashbacks’ with these re-experiences resulting in severe anxiety and becoming in effect a phobic stimulus which cannot be avoided. In PTSD, the nature of the ‘phobic’ experience is of course particularly variable. This, and the nature of the precipitating events, makes reproduction of the experience potentially impossible in vivo. Current treatment approaches often therefore include graded exposure to a narrative account by the sufferer or exposure to the situation ‘in sensu,’ that is, in the person’s imagination. VR, however, has the potential to produce personalized experiences, and therefore possibly graded exposure to elements of a traumatic experience. Where there are similar experiences of triggers for groups of people, VR scenarios have been constructed and used, for example, in the treatment of war veterans [14]. It will of course be more resource intensive to produce VR for more individual scenarios. The use of VR exposure for PTSD without the ready availability or presence of a therapist may not be appropriate for more severe PTSD, but it could significantly add to the therapeutic options.

4. Engaging patients in treatment

When considering the treatment of generalized anxiety, PTSD and more complex cases of social anxiety and agoraphobia, the use of VR is likely to be more complex, with a focus not only on desensitization to particular stimuli but also on reducing anxiety related to internal cognitive processes. In addition, anxiety disorders tend to occur co-morbidly with major depressive disorder and other disorders such as bipolar disorder, complicating their treatment. Anxiety is a common symptom in major depression and the point at which a separate diagnosis is made is contentious [15]. Treatment guidelines have generally recommended CBT as first-line treatment for most anxiety disorders in developed countries and in LMICs [16]. Some guidelines for treatment of anxiety disorders, acknowledging the issues of cost and access, have emphasized on-line computer programs which have good clinical trial evidence of effectiveness [8]. However, the degree of generalizability of these programs is not clear, with good engagement possibly limited to a subgroup of more motivated patients. In this area, the presentation of material in a VR environment may have the potential for better engagement. Other examples of VR supporting therapies in a novel way and possibly increasing engagement are its use to support mindfulness meditation for generalized anxiety [17], and in creating virtual environments in which therapists encourage patients to challenge their cognitions as they arise [18].

Intriguing new research aims to increase engagement in remote therapy by employing customizable therapists who act as guides in the therapy process. The degree to which these avatars are controlled by software or by actual therapists can vary depending on clinical state. It is also possible to link such avatars to real time physiological feedback (heart rate, galvanic skin response, actigraphic activity data) to link their response to the person’s current physiological state [19].

5. Expert opinion

While studies of VR in anxiety disorders and in depression have been published from the early 2000s the literature is still beset by issues such as small sample sizes, variable measurements, variable inclusion criteria, and a wide range of methodologies. Very few studies have followed patients up longer term. These issues are, however, common to research in most psychological treatments and there is no simple answer to these problems, with research necessarily encompassing more restrictive efficacy studies (highly controlled, tight inclusion/exclusion criteria, multiple measures) at one end of a spectrum to effectiveness trials (broader, more clinically oriented) at the other. In 2019, a group of experts described the current state of VR research (in mental health, not specifically in anxiety disorders) as ‘Wild West’ with a lack of clear guidelines and standards” [20]. The group produced a series of recommendations covering the stages from initial design to large-scale clinical trials, emphasizing collaboration with end users – patients and clinicians – from an early stage.

In our opinion, some of the most important recommendations of this group include increasing the input of people with lived experience in several areas. For example, they recommend obtaining user feedback at all stages of prototype development with iterative improvement in design, understanding how VR fits into different contexts in patient’s lives and understanding the perspectives of people from a wide range of ages and ethnicities [20].

VR is a rapidly advancing development in the treatment of anxiety disorders and other mental health conditions. Potential advantages are a reduction in therapist input and possible advantages in efficacy when VR is combined with existing treatments. Technology allows for a high degree of sophistication and development is rapid. However, care should be taken in translation into practice in the treatment of what are often complex and highly individual conditions.

Declaration of interest

R Porter has been provided with the use of computer software by SBT-Pro. He has also received support for travel to educational meetings from Servier and Lundbeck. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.