The efficacy of virtual reality exposure therapy (VRET) in treating specific phobias

By Glyn Hupalo

Virtual reality (VR) can be described as an “artificial, immersive three-dimensional (3D) environment with interactive sensory stimuli” (Andersen, 2023, p. 1). While VR technology was originally intended to target the gaming industry, it is now used in a range of fields from education to healthcare (Hamad & Jia, 2022). In psychotherapeutic settings, VR is often used to facilitate exposure therapy as the technology allows facilitators to create individualised scenarios that mimic real-life environments and situations (Andersen et al., 2023). One use case for this form of therapy is to treat specific phobias.

Specific phobias involve the experience of excessive or extreme distress, fear, or anxiety when exposed to, or thinking about, a specific stimulus or situation (Alvear-Suárez et al., 2019; American Psychiatric Association, 2013; Antony et al., 2006; Eaton et al., 2018; World Health Organization, 2022). Estimates indicate specific phobias are among the most common mental health disorders (Zsido, 2017), and are associated with a large number of comorbidities (such as depression, anxiety disorder and personality disorders) as well as elevated rates of attempts at suicide among individuals diagnosed with a specific phobia (American Psychiatric Association, 2013). Despite these alarming factors, only a small minority of people seek treatment even though there is a range of available therapy options (Eaton et al., 2018).

Virtual reality exposure therapy (VRET) is one treatment used to help those with specific phobias. It uses the principles of exposure techniques to help individuals face fear-inducing situations in a controlled, virtual setting (Cho et al., 2023). The first published study in which VR was used as a means of therapeutic treatment for specific phobias (acrophobia) was a pilot study conducted by Rothbaum et al. (1995). To understand the full impact of VRET, this literature review evaluates current research on its effectiveness in treating specific phobias. Diagnosis of specific phobias and common treatments will be outlined, and a range of exposure therapies will be detailed to show how VRET emerged. Four specific phobias will then be discussed in depth to investigate where VRET's strengths lie.

A systematic literature review was conducted using multiple keyword searches in Scopus, Google Scholar, PubMed, and Torrens University Library to find relevant research articles published between 1995 (the start of VR phobia treatments) and today. Bibliometric analysis was conducted on the search results using Biblioshiny to identify key authors and papers on the subject.

Diagnosis of Specific Phobias

Preliminary surveys and questionnaires such as The Severity Measure for Specific Phobia (Craske et al., 2013) can be administered to self-diagnose a specific phobia, but to receive treatment, an official medical diagnosis may be required. Medical professionals will refer to the Diagnostic and Statistical Manual of Mental Health Disorders Fifth Edition (DSM-5) or International Classification of Diseases 11th Revision (ICD-11) to ascertain the specific diagnostic criteria. For specific phobias, the criteria are: Excessive fear or anxiety when directly exposed to, or, in anticipation of exposure to a specific object or situation; active avoidance of the specific object or situation, or enduring it with intense fear or anxiety that has lasted longer than 6 months; and the symptoms experienced are not related to or explained by another mental disorder (American Psychiatric Association, 2013; World Health Organization, 2022).

The DSM-5 divides ‘specific phobia’ into five subtypes: animal, natural environment, blood-injection-injury, situational, and other, with each subtype containing distinct phobias. For example, the subtype ‘animal’ may contain various phobias specific to an individual type of animal such as fear of spiders (arachnophobia), fear of snakes (ophidiophobia), and fear of birds (ornithophobia) (American Psychiatric Association, 2013; Antony et al., 2006). A diagnosis of multiple specific phobias is common with around 75% of individuals fearing more than one specific object or situation (American Psychiatric Association, 2013). Whether officially diagnosed or not, individuals facing fear and anxiety concerning a specific phobia may experience significant disruption to their day-to-day lives (Antony et al., 2006). Often, individuals will implement avoidance tactics to reduce their anxiety and fear, however, this can reduce the overall quality of their lives (Eaton et al., 2018).

Treatment of Specific Phobias

Search results related to treatment methods for specific phobias highlighted Eye Movement Desensitization Reprocessing (EMDR), Hypnotherapy, Cognitive Behavioural Therapy (CBT), and Exposure Therapy as the most commonly used treatments. In a recent review of specific phobias, Eaton et al. (2018) noted that they were unaware of any studies that compared the effectiveness of different treatments. Therefore, the findings below demonstrate the use of each treatment type in comparison to a control group.

Eye Movement Desensitization Reprocessing (EMDR)

EMDR stands as an integrative form of client-centred psychotherapy, intending to reprocess traumatic life experiences by addressing images, thoughts, emotions, and other elements linked to distressing memories (Laliotis & Shapiro, 2022; Russell & Shapiro, 2021). To accomplish this, individuals are exposed to distressing stimuli while simultaneously employing EMDR techniques like eye movements, tapping, or auditory cues (EMDR Institute, 2020). Leeds (2016) suggested that while more research is required into EMDR as a treatment method for specific phobias, consideration could be given to using it as an initial treatment method if the specific phobia being treated has a traumatic origin.

Hypnotherapy

Hypnotherapy originates from hypnosis which is described as when an individual experiences reduced peripheral awareness while maintaining a focused state of attention in which they are highly susceptible to suggestion (Elkins et al., 2015). In a therapeutic setting, this highly susceptible state achieved by hypnosis is often combined with various therapies such as CBT and exposure therapy (Hirsch, 2018; Spiegel, 2014). It is this combination of hypnosis and therapy that enables the conscious imagination to absorb new information and bring about real therapeutic change (Robertson, 2013). Research on the use of hypnotherapy to treat specific phobias tended to focus on dental phobias (e.g., Gerhard Wolf et al., 2022; Venkiteswaran & Tandon, 2021).

Cognitive Behavioural Therapy (CBT)

CBT is a therapeutic model that posits people's behaviour is influenced by their emotions (American Psychological Association, 2017a). When discussing techniques used in CBT treatment, there are two types - cognitive and behavioural - which, as their names suggest, target specific cognitions and behaviours to modify or change them to create greater outcomes than are currently being experienced (Fenn & Byrne, 2013). When treating specific phobias with cognitive techniques, the therapist might work towards identifying and shifting the individual's thoughts and beliefs that occur when in direct contact with the source of their phobia. Alternatively, when treating specific phobias with behavioural techniques, the therapist deliberately exposes an individual to the source of the phobia to decrease and change the reactions and behaviours towards it.

Exposure Therapy

Exposure therapy is the process of progressively exposing an individual to the source of their phobia to desensitise and change their relationship with it. In the treatment of specific phobias, exposure therapy is considered one of the most effective and widely implemented treatments (Eaton et al., 2018). This may be because exposure therapy is based purely on the treatment of phobias and fears, whereas alternative treatments, while effective in their own ways, were not created intentionally for treating specific phobias (American Psychological Association, 2017b). Throughout its development, several variations of exposure therapy have emerged and are widely used today.

Evolution of Exposure Therapy and the Emergence of VRET

Based on Ivan Pavlov’s theory of classical conditioning (Vinograd & Craske, 2020), exposure therapy as a treatment first emerged in the 1950s during the rise of behaviourism. The earliest forms of exposure therapy created by Joseph Wolpe focused on the idea of systematic desensitisation (Jacquart et al., 2022). In this process, individuals dissect their phobia into a hierarchy to allow for gradual exposure. They are then taught relaxation techniques to be used during exposure, and finally, they receive gradual exposure to the source of their fear (Vinograd & Craske, 2020). Over time, the systematic desensitisation was replaced by the habituation model, which built on the idea of creating hierarchies of an individual's fear but also established the individual's level of fear during each exposure. Once an individual reached a mid to high level of fear, the exposure was terminated to avoid overwhelming the patient (Vinograd & Craske, 2020). Later, both the Emotional Processing Theory and the Inhibitory Learning Model were developed with a focus on the role memories of fear play in phobias, with the goal of creating new, less anxiety-inducing, memories associated with the source of fear. Through the course of exposure therapy development, the majority of exposures were conducted with real-life situations and objects (in vivo exposure). More recently, as exposure therapy has become synonymous with CBT, other types of exposure therapy have emerged. These include visualising the source of phobia rather than direct exposure to it (imaginal exposure), desensitisation of somatic experiences connected with specific phobias (interoceptive exposure), and most recently, the use of VR technology to indirectly expose an individual to the source of their fear in a simulated environment (virtual reality exposure therapy) (Jacquart et al., 2022).

In Vivo Exposure Therapy (IVET)

Considered the most common form of exposure therapy (Simos & Hofmann, 2013), IVET involves gradual real-life interaction with situations or stimuli that instil fear or anxiety in an individual diagnosed with a specific phobia (American Psychological Association, 2017b; Jiang et al., 2020; Simos & Hofmann, 2013). Exposures are often repeated over multiple sessions (Simos & Hofmann, 2013), however, some studies have demonstrated that single exposure sessions for specific phobias can also be effective (e.g., Odgers et al., 2022; Zlomke & Davis III, 2008). It is believed that by exposing individuals to fear-inducing situations or stimuli, they will slowly become desensitised to the experience and, over time, learn new information and create new beliefs that reduce or eliminate their fear (Jiang et al., 2020). For IVET to be successful, it is important that individuals undergoing treatment are not being aided by safety signals or behaviours as reliance on these will inhibit the individual's ability to learn the coping skills required to manage their fear on their own (Simos & Hofmann, 2013). IVET is currently regarded as effective in the treatment of multiple specific phobias such as microzoophobia (fear of small animals) (Botella et al., 2016), arachnophobia (fear of spiders) (Michaliszyn et al., 2010), and blood-injection-injury phobia (Jiang et al., 2020).

Imaginal Exposure Therapy

Imaginal exposure therapy involves an individual entering an extremely relaxed state to visualise interactions with objects and situations that when experienced in real life may induce fear and anxiety (American Psychological Association, 2017b). It is not uncommon for imaginal exposure therapy and hypnosis to be used in conjunction as hypnosis assists in creating the state of deep relaxation required for optimal visualisation (Robertson, 2013). Through the process of visualisation, an individual can control the conditions in which they experience their phobia as well as the level of exposure they have to it. While this provides an increased level of control in exposure, Difede & Hoffman (2002) and van Minnen et al. (2010) both stated that there is a possibility it can lead to an exacerbation of symptoms. Instead, it is better used as an additional treatment alongside more commonly used treatments for specific phobias (Wiederhold & Wiederhold, 2003).

Interoceptive Exposure Therapy

Unlike the aforementioned types of exposure therapy, interoceptive exposure therapy involves focusing on an individual's somatic experience rather than their cognitive experience. The experience of fear and anxiety when exposed to a specific object or situation will often be accompanied by physical sensations which then become associated with exposure to the specific object or situation. As a result, fear and anxiety can be experienced in situations unrelated to specific phobias if the physical sensations connected with the phobia are in some way present. To counteract this, interoceptive exposure therapy works to purposefully induce the associated physical sensations for an individual to reduce the sensitivity of experiencing them (American Psychological Association, 2017b; Boettcher et al., 2016). Through multiple experiences of these physical sensations without any negative outcomes, they slowly become disconfirmed as the expected outcome (Simos & Hofmann, 2013), leading to reduced anxiety levels, and making experiencing them more tolerable (Boettcher et al., 2016).

Virtual Reality Exposure Therapy (VRET)

The most recent of the listed exposure therapies, VRET leverages VR technology to allow phobic individuals to be exposed to fear and anxiety-inducing objects and situations that appear real but are computer-generated (Price et al., 2008). Exposure in this virtual world is facilitated through the use of VR components which began as a collection of sensors, cameras, and a special helmet (Simos & Hofmann, 2013), but as technology has evolved, this equipment has become smaller, lighter, and more portable. While similar to IVET, VRET allows for customisation and control of all elements of the exposure experience (Moldovan & David, 2014) meaning treatment can be tailored specifically to an individual's comfort levels and fully controlled by the therapist (Rothbaum et al., 2016). Two key elements that contribute to the VRET experience are presence and immersion. The greater the creation of presence, the more an individual will experience the virtual world where their exposure takes place as real, making them more likely to engage in the exposure experience (Witmer & Singer, 1998). Similarly, immersion is crucial to effective VRET as it determines the level at which an individual will become absorbed in the virtual world (Silva et al., 2016). VRET has been trialled as a treatment for a variety of specific phobias such as acrophobia (Coelho et al., 2008,2009; Moldovan & David, 2014), arachnophobia (Côté 2005; Garcia 2002; Bouchard 2006), and aviophobia (Baños et al., 2002; Freitas et al., 2021; Price et al., 2008; Rothbaum et al., 2000, 2006).

While each form of exposure therapy can be used to treat a range of conditions, research suggests that IVET and VRET have been most successful when it comes to specific phobias. Before the advent of VR technology, exposure therapy was only possible in vivo. However, with the introduction of VRET it is now possible to receive the same exposure experience as provided by IVET, but with a greater degree of safety, customisation, and control over the exposure than will ever be possible in IVET. In addition, as the world continues to become more digitally oriented, people may begin to prefer the use of VR treatment options such as VRET because they offer access to effective mental health services from virtually any location. Greater levels of access may lead to an increase in people seeking and receiving treatment for specific phobias, which they might otherwise have avoided if VRET was not available. It is for these reasons that VRET shows great promise as a treatment for specific phobias.

Treating Specific Phobias with VRET

To ensure a thorough investigation into the use of VRET in the treatment of specific phobias, four of the five subtypes of ‘specific phobia’ as per the DSM-5 (American Psychiatric Association, 2013) will be investigated. The subtype ‘other’ was omitted due to its close resemblance and connection to the other four subtypes. It is hoped that by investigating multiple subtypes of ‘specific phobia’, a more accurate conclusion can be drawn about VRET’s efficacy as a treatment for specific phobias in general.

Zoophobia

Definition

Zoophobia is defined as a severe fear of animals (Cleveland Clinic, 2022a). While considered a phobia in itself, the term zoophobia serves more as a general overarching term to describe a group of phobias relating to specific animals such as arachnophobia (fear of spiders), ophidiophobia (fear of snakes), and katsaridaphobia (fear of cockroaches) (Alvear Suárez et al., 2017). Of the five categories of specific phobia listed in the DSM-5 (American Psychiatric Association, 2013), ‘animal’ has been found to have the highest prevalence (Becker et al., 2007; Oosterink et al., 2009) and one study found that symptoms of zoophobia first occur around the age of 8 years old and predominantly among females (Ajdacic-Gross et al., 2016).

Diagnosis

Due to the multiple phobias comprising zoophobia, symptoms and methods used for diagnosis may vary greatly. Alvear Suárez et al. (2017) noted that when individuals are exposed to an animal they fear, they may exhibit physical symptoms such as sweating, trouble controlling muscles, elevated heart rate, and rapid breathing. In addition, they may also experience emotional symptoms like extreme anxiety. In addition, when exposed to a specific animal, an individual with zoophobia may experience revulsion rather than fear at the sight, smell, or touch of the animal (Anxiety UK, n.d.). In minor cases, zoophobia may result in a person avoiding places where they may encounter animals, such as parks or farms, however, in more extreme cases it may lead to agoraphobia, a condition in which people develop a fear of leaving their homes (Alvear Suárez et al., 2017; Anxiety UK, n.d.). Due to the broad nature of zoophobia, treatment is not commonly sought after (Alvear Suárez et al., 2017). The low rate of individuals seeking treatment may also be a result of a lack of tools to provide a diagnosis of zoophobia or any of the specific animal phobias that come under the banner of zoophobia (Zsido, 2017).

Efficacy of VRET

In gathering research, the majority of studies relating to the treatment of zoophobia using VRET focused on the fear of a specific animal rather than zoophobia itself. Therefore, the subsequent information in this section will refer to data gathered about specific animal phobias but will contribute to the overall area of zoophobia. The most commonly researched animal phobia was arachnophobia, which produced a disproportionately greater quantity of research results that can be split into three categories: studies conducted solely testing VRET (Bouchard et al., 2006; Côté & Bouchard, 2005; Garcia-Palacious et al., 2002), studies measuring VRET alongside IVET (Hoffman 2003; Michaliszyn 2010; Miloff 2019), and studies using VRET alongside additional treatment methods (Shiban 2013; 2015).

In all studies, VRET was shown to be effective at reducing the feelings of fear and anxiety experienced when exposed to spiders. When compared to IVET and other treatment types, VRET was found to be as effective and in some cases more effective than IVET, and in all cases more effective than other treatment methods. Similar levels of efficacy were recorded when investigating the use of VRET to treat a fear of snakes (Polák et al., 2016; Zsido, 2017), a fear of cockroaches (Alvear Suárez et al., 2017), and a fear of small animals (Suso-Ribera, 2019).

Acrophobia

Definition

Acrophobia is an extreme fear of heights that often involves physical symptoms and a strong inclination to avoid elevated situations such as stairs, balconies, mountains, and bridges (Coelho, 2008, 2009; Guo et al., 2023). While it is estimated that 1 in 20 adults suffer from acrophobia (Coelho, 2009), very little is known about the specific causes of this debilitating condition (Coelho, 2008).

Diagnosis

Acrophobia may be accompanied by physical symptoms or a strong inclination to avoid elevated situations, and this alone may provide enough evidence that an individual suffers from acrophobia. A recent study by Cheng et al. (2023) confirmed that the movements made by individuals with acrophobia are noticeably different to those without acrophobia and the study's findings provide a foundational basis for the preliminary screening of acrophobia. The more common treatment methods for acrophobia include desensitisation, IVET, VRET, neurolinguistic programming, negative practice, and oppositional action (Arroll et al., 2017). While each of these treatments demonstrates alleviation of acrophobia to some level, Arroll et al. (2017) noted that a movement away from desensitisation and IVET towards VRET is occurring.

Efficacy of VRET

According to Coelho et al. (2009), VRET has been used since 1995 to treat acrophobia and has become a dominant treatment for multiple anxiety disorders. Not only is VRET considered a preferred and effective treatment for acrophobia, but VR technology has also contributed to the ability to rapidly screen for and diagnose acrophobia (Cheng et al., 2023). From early pilot studies when VR technology was limited and expensive (e.g., Schuemie et al., 2000; Coelho et al., 2008, 2009; Emmelkamp et al., 2002) to more recent studies (e.g., Abdullah & Ahmed Shaikh, 2018; Donker et al., 2018,19; Raeder et al., 2019), VRET appears to have the evidence base required to support its efficacy as a treatment. The technology used allows for a high level of customisation, making it possible to control the degree of exposure in line with each individual's treatment needs (Moldoveanu et al., 2023). In addition, Schuemie et al. (2000) found a correlation between the level of fear displayed and the level of detail contained in the virtual world, indicating that exposure to heights may be more possible in VR than in vivo as long as the graphic content remains unrealistic. VRET can also be considered a time-effective treatment with Coelho et al. (2009) finding that patients receiving VRET required less exposure time than participants receiving traditional treatments, indicating not only the effectiveness of the treatment but also its potential to decrease the amount of time required for treatment. Finally, as VR technology improves, it becomes more affordable and accessible for use in the treatment of anxiety disorders such as acrophobia (Emmelkamp et al., 2002) and it may soon even become commonplace for individuals to self-administer these treatments, with some studies (e.g., Donker et al., 2019; Hong et al., 2017) trialling self-guided treatments for acrophobia which have shown large reductions in symptoms post-trial and at a three-month follow-up.

Blood-Injury-Injection Phobia

Definition

Blood-injection-injury phobia (BII) gained its name since individuals with BII often faint or experience anxiety when exposed to blood, injury, mutilation, needles, and injections (Ritz et al., 2010; Wani et al., 2014). It is considered one of the most widespread subtypes of specific phobia after zoophobia and acrophobia (Eaton et al., 2018) and is the only phobia of the subtypes which is experienced equally by men and women (American Psychiatric Association, 2013; Berg Johnsen et al., 2023). BII can result from anticipation of injury or being exposed to blood or medical procedures and can lead to avoidance behaviours (American Psychiatric Association, 2013; Çavuşoğlu & Dirik, 2011). As a result, individuals who experience BII are more likely to avoid hospitals, dental surgeries, and other medical-related locations (Kiss et al., 2022). This avoidance may be possible with other specific phobias such as zoophobia or acrophobia, however, in BII it may lead to individuals avoiding or refusing important medical check-ups or procedures that may in turn harm their overall health (Ritz et al., 2010; Wani et al., 2014). While fear resulting from exposure to blood, injection, or injury can trigger anxiety, Olatunji et al. (2007) and Tolin et al. (1997) posited that some individuals may experience disgust about these phenomena rather than fear.

Diagnosis

According to the DSM-5 (American Psychiatric Association, 2013), individuals with BII may often experience fainting or near-fainting, elevated blood pressure, and accelerated heart rate when exposed to triggering situations.

Efficacy of VRET

In the process of researching VRET in the treatment of BII, very little evidence was available compared to the other subtypes of specific phobia. This appears to be in line with the work of Jiang et al. (2020) and Gujjar et al. (2019) who both stated that limited evidence of the efficacy of VRET in treating BII exists. Gujjar and colleagues have produced three studies (Gujjar et al., 2017; 2018; 2019) that demonstrated the efficacy of VRET as a treatment. All patients in the 2019 study who received VRET as a treatment showed a reduction in anxiety levels, however, the sample sizes of each study may be considered too small to demonstrate efficacy, with the respective studies containing two, 10 and 30 subjects. Jiang et al. (2020) who studied the efficacy of single-session VRET for treating BII found that it may be better as an interim treatment before implementing IVET. They further stated their belief that VRET is insufficient to be implemented as a standalone treatment (Jiang et al., 2020). With a lack of research, it is difficult to conclude that VRET is an effective treatment for BII, indicating that the currently recommended treatments, namely IVET and applied tension, may be more appropriate and effective (Ayala et al., 2009; Mednick & Claar, 2012; Wannemueller et al., 2018). While VRET studies into the treatment of BII yielded few research results, a growing body of research into using VR technology for treating pain when receiving needles (e.g., Chad et al., 2018; Gao et al., 2023; Lluesma-Vidal et al., 2022) adds further weight to the suggestion that VR may be effective as a distraction technique rather than a treatment.

Aviophobia

Definition

Aviophobia, also referred to as aerophobia or fear of flying, is a specific phobia in which individuals have an immense fear of flying in an aeroplane (Cleveland Clinic, 2022b). It is estimated that 10 - 35% of the people residing in North America and Western Europe experience aviophobia to some extent (Oakes & Bor, 2010). Classified in the DSM-5 as a situational phobia, a subtype of specific phobia, it is likely an individual with aviophobia will also experience additional specific phobias within the same subtype (Laker, 2012). This may be explained by Oakes & Bor (2010) who suggested that anxiety experienced while flying may be caused by phobias other than aviophobia, such as acrophobia (a fear of heights) or claustrophobia (fear of small or confined spaces). Cleveland Clinic (2022b) further dissected aviophobia into specific aspects of flying which may induce the anxiety and fear responsible for aviophobia. These include boarding a plane, take-off, turbulence, and landing. While flying may not be an activity most individuals are required to undertake regularly, aviophobia has the potential to impede an individual's ability to visit family or travel for specific reasons such as work (Trumpf et al., 2010).

Diagnosis

When considering the diagnosis of aviophobia, the Flight Anxiety Situations Questionnaire (FAS) and the Flight Anxiety Modality Questionnaire (FAM) are the two currently most utilised diagnosis questionnaires (Laker, 2012). Other indicators that an individual may have aviophobia are demonstrated via cognitive responses such as fear of crashing or dying while flying, and somatic responses such as elevated blood pressure and heart rate, hyperventilation, and gastric upset (Bor, 2007; Oakes & Bor, 2010).

Efficacy of VRET

When compared to IVET, VRET is more cost-effective and individuals have a higher degree of control over the exposure experience such as weather conditions and take-off and landing times (Baños et al., 2002; Freitas et al., 2021; Price et al., 2008; Rothbaum et al., 2000, 2006). VRET also provides the ability to experience multiple flight exposures within a single session (Baños et al., 2002) in the privacy of a therapist's office or patient's home (Price et al., 2008). Studies aimed at determining the efficacy of VRET as a treatment for aviophobia appear to be decreasing in number, with most of the available research having been produced between 2001 and 2006. Between 2006 and 2013, only two studies were published (Cárdenas et al., 2009; Rus-Calafell et al., 2013). This trend could suggest that while VR technology is constantly evolving, current VRET treatment methods may not be. Of the four articles written post-2013, three (Donker et al., 2022; Fehribach et al., 2021; Lacey et al., 2023) focused on self-administered VRET treatment via a mobile phone app, detailing successful reductions of fear and anxiety connected to aviophobia. This may eliminate the need for therapist-supervised VRET and indicate a new trend in self-administered VRET research.

The majority of other studies tested VRET’s effectiveness alongside IVET (Anderson et al., 2006; Maltby et al., 2002; Ribé-Viñes et al., 2023; Rothbaum et al., 2006), imaginal exposure therapy (Rus-Calafell et al., 2013; Wiederhold et al., 2002), relaxation techniques (Mühlberger et al., 2001), and CBT (Mühlberger et al., 2003, 2006). In all cases, VRET was found to be effective or as effective as other aviophobia treatments.

Conclusion

This literature review aimed to understand the full impact of VRET in treating specific phobias in comparison to other forms of exposure therapy and alternative treatment methods. It has highlighted the benefits of VRET as a treatment method and demonstrated the promise VRET has shown in providing effective exposure to phobic stimuli in controlled and customisable environments. In addition, VRET’s time and cost-effectiveness and potential for self-administered therapy are strong benefits, as well as its ability to address numerous specific phobias.

While it has demonstrated effectiveness in treating specific phobias such as acrophobia, zoophobia, and aviophobia, the existing research on VRET's efficacy for specific phobias is not uniform across all subtypes. For example, the evidence for its use in treating BII remains limited, with some suggesting it may work better as an interim treatment rather than a standalone therapy. To fill some gaps in current research, future studies should focus on larger sample sizes and more rigorous methodologies to provide a more comprehensive understanding of VRET's effectiveness.

With a growing body of empirical studies demonstrating its effectiveness (Price et al., 2008), and rapid advancements in technology allowing for constant improvements to already existing treatment methods, VRET appears to have many advantages over standard treatments (Baños et al., 2002). In the future, VRET may play an even greater role in the treatment of specific phobias, especially when combined with traditional therapeutic approaches. As technology continues to advance, we can anticipate further refinement and expansion of VRET's applications, potentially revolutionising the way specific phobias are treated. Researchers and clinicians must collaborate to explore its full potential and address unanswered questions to improve the well-being of individuals struggling with specific phobias.

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