Technology is revolutionising psychological therapies. From mobile apps to virtual reality therapies (VRT), gamifying the therapy experience. It all sounds futuristic and exciting, but beyond the buzz, can these tools make a practical difference in people’s lives? Smith et al. are expanding on previous research to find out whether immersive VRT can do just that for people diagnosed with schizophrenia.
Schizophrenia is a mental illness characterised by hallucinations, delusions, and differences in thinking and perception. A large majority of people who are diagnosed with schizophrenia hear distressing voices. However, hearing voices is not unique to schizophrenia and is not always a distressing or negative experience. Treatment options for people who find their voices distressing are very limited. Medication and cognitive behavioural therapy (CBT), while helpful for some, are less effective at treating this than we would hope.
Research has shown that some people report that their voices are personified, with names, identities, and opinions of their own. Based on this knowledge, relational psychotherapies were developed. This approach involves voice-hearers interacting and conversing with their voices. Challenge-VRT is based on a relational approach called AVATAR therapy (read about the AVATAR therapy in this Mental Elf Blog), where a therapist helps the voice-hearer stand up to their dominant voice and develop confidence using a tailored digital avatar.
Previous pilot small-scale studies of relational VRTs (e.g., Leff et al., 2014; du Sert et al., 2018; Dellazzizo et al., 2021) indicated potential benefits, but these studies weren’t large enough for the results to be reliable. A recent well powered UK based trial of Avatar therapy found a reduction in voice-related distress at 12 weeks but not at 28 weeks compared to treatment as usual, suggesting initial gains may not be maintained (Garety et al., 2024).
Danish researchers have now conducted a fully powered multi-site randomised controlled trial of an approach that allowed for more careful adjustment of the avatar by the therapist in real time to refine and personalise the approach.
There have been a number of studies of Avatar therapy for voices for which new treatments are badly needed, but is the hype justified?
Methods
The study recruited 271 adults diagnosed with a schizophrenia spectrum disorder (ICD-10) from mental health services across three regions in Denmark. To take part, people had to be experiencing distressing voices for at least three months that hadn’t responded to antipsychotic medication. All participants were receiving ongoing psychiatric care and had no changes in medication in the 4 weeks leading up to the trial. People were excluded if they couldn’t identify a dominant voice, were involved in substance misuse, had neurological, or vision problems, or were unable to engage in assessments.
They were randomly assigned to receive the intervention (Challenge-VRT) or enhanced treatment as usual, to test if the intervention is more effective at reducing the severity of voices at 12 weeks (end of treatment). Those assigned to the intervention received seven sessions and two booster sessions of the manualised Challenge-VRT therapy model, which included three phases (reclaiming power, self-worth, recovery).
They created a digital avatar which was controlled by the therapist in real time when they interacted with it in the 3D environment through a VR headset. During avatar therapy, the participant wore an Oculus Rift VR headset and noise-cancelling headphones to create an immersive experience of engaging with the representation of their voice.
Enhanced treatment-as-usual was the participants’ normal psychiatric outpatient care, which was either early intervention services that provide 2 years of intensive treatment or community teams with less frequent sessions. Those under community teams were asked to provide at least seven additional supportive counselling sessions in order to try and match treatment intensity across groups. The sessions did not follow a structured therapy manual and were managed by the mental health services.
The outcome assessments were conducted by research assistants who did not know which group participants were allocated to, and measures were taken to ensure they remained blinded to the allocation. The primary outcome (severity of the auditory hallucinations) was measured by the Psychotic Symptoms Rating Scales for Auditory Hallucinations (PSYRATS-AH). They also used other measures to assess secondary outcomes, including voice frequency and distress, perceived power of the voice, social functioning and coping and assertiveness in responding to voices. Assessments were conducted before starting the therapy, at 12 weeks and 24 weeks.
Participants wore an Oculus Rift VR headset and noise-cancelling headphones to create an immersive experience of engaging with the representation of their voice.
Results
The authors state:
Compared with the control group, Challenge-VRT significantly reduced the severity of auditory hallucinations as measured by PSYRATS-AH total score at 12 weeks and significantly reduced voice frequency compared with enhanced treatment-as-usual.
The -2.26 reduction in severity on the PSYRATS-AH scale falls below what the authors suggested would demonstrate a clinically meaningful difference (3 to 5 points). The finding was statistically significant (p=0.027), meaning that it is unlikely to be due to chance. However, the effect size is small (Cohen’s d= 0.27) and the confidence interval narrowly excluded zero (95% CI= –4.26 to –0.25), suggesting marginal statistical robustness. As with the last UK based trial (Garety et al., 2024), the change was no longer significant at the 24-week follow-up, meaning that it is unlikely that the therapy had lasting effects in reducing voice severity.
There was also a very small reduction of -0.84 (p=0.027) in voice frequency compared with the control group. This result was also observed at the 24-week follow-up in a similar -0.86 difference in voice frequency (p=0.034). [95% CI –1·65 to –0·07]. While it was sustained at the follow-up, the effect size was again small (Cohen’s D 0.29).
In the VR group, four people reported their voices had stopped completely at 12 weeks and eleven at 24 weeks. Participants rated higher satisfaction with VR therapy compared with the enhanced treatment-as-usual group, suggesting that the intervention was engaging and acceptable. The authors did not find any other (significant) differences between the VR therapy and enhanced treatment-as-usual group.
The authors state that overall, Challenge-VRT was well tolerated but 37% participants experienced temporary worsening of symptoms. During the 12-week intervention, 30% of participants in the Challenge-VRT group were admitted to inpatient wards, compared with 22% in the enhanced control group. Serious adverse events potentially linked to the intervention included five hospital admissions due to worsening auditory verbal hallucinations and one episode of self-harm in a participant with a history of repeated self-injury, possibly triggered by therapy participation. The number of suicide attempts was similar across groups, and none were considered related to the trial. Female participants reported more adverse events than males, including higher rates of psychiatric admissions, suicide attempts, and greater simulator sickness scores. This suggests that the treatment can be emotionally intense and potentially destabilising.
Safety findings suggest the approach can be intense and potentially destabilising.
Conclusions
The Challenge-VRT trial showed that immersive VR therapy can reduce the severity and frequency of distressing voices in people with schizophrenia who haven’t responded well to medication. More people in the VR group stopped hearing voices, but this is not always everyone’s goal. What matters most is how therapy changes a person’s relationship with their voices and improves their quality of life, and unfortunately, this paper doesn’t provide any detailed insight into this. While the results are promising, they are not game-changing.
Strengths and limitations
Strengths
- Large and well powered trial. The assessor-blind, multi-site randomised controlled trial included over 250 participants and was well powered, which supports the reliability of the findings.
- High engagement and completion rates (79%). The authors demonstrated that the majority of participants were willing and able to engage with Challenge-VRT when supported, indicating that this immersive technology might be acceptable for people diagnosed with schizophrenia.
- Lived experience input. The intervention was refined with people who have lived experience of hearing voices, to ensure the design, content and delivery of the intervention were relevant and acceptable.
- Intervention length. The intervention was brief, including 7 sessions with the option of two booster sessions, which could make Challenge-VRT easier to complete and more cost-effective than a longer intervention.
- Delivered in routine services. The intervention was delivered in local clinics by professionals with varying levels of experience, providing evidence that it can be implemented without the need for experienced VR therapists. However, further research is needed to see if the intervention could be scaled by being delivered by a wide range of professionals. 8 out of the 11 people who delivered the intervention were psychologists, so the groups were not balanced or powered enough to find out if this moderated the effects.
Limitations
- Limited generalisability and lack of diversity. The authors recruited patients with schizophrenia from Danish clinical services, limiting generalisability. The sample was 61% female with a mean age of 33, and there was no data gathered on ethnicity, so we can’t apply the findings to the broader population of voice hearers.
- Not all voices are personified. From my experience working on a trial for distressing voices, not all voice hearers have personified or conversational voices, yet this is central to how Challenge-VRT works. This wasn’t an inclusion criterion so participants who didn’t have conversational voices may have struggled to engage meaningfully with the avatar dialogues, potentially explaining the modest findings. This undermines the study’s internal validity and may have overlooked patients who might have benefited most.
- Unclear adverse event monitoring framework. It’s not clear how thoroughly the safety data was collected and analysed, so it’s difficult to determine whether the spikes in symptoms reported caused genuine harm. If Challenge-VRT had been regulated as a medical device, the authors would have needed to use a standardised system for reporting and monitoring adverse events and their causality. This would give much more confidence in ensuring patient safety and scientific transparency.
- Technology issues. Therapists reported that almost half (48%) of participants had technological issues in at least one of the seven therapy sessions. This raises questions about how easily this could be delivered in routine care. If technological issues interrupted the sessions from running smoothly, it also may have limited how effective they were overall.
- Anxiety-inducing environment. Some patients were initially overwhelmed by the immersive 3D technology and had to have additional time to manage anxiety. This reduced the time participants were exposed to the treatment and may have limited its effectiveness.
- Missing data. Some measures couldn’t be completed by everyone. For example, people who stopped hearing voices or didn’t experience command voices couldn’t fill in certain questionnaires. This left gaps in the data, making it harder to get a full picture of how the therapy worked for everyone.
- Variation in enhanced treatment-as-usual. The (enhanced) treatment-as-usual group did not follow a set manual and the frequency and type of support received varied between participants. Therefore, we can’t be certain how much of the difference in outcomes is because of the therapy.
- Lack of digital control condition. The inclusion of a more active, potentially digital, control condition may have allowed for a clearer assessment of effectiveness by reducing potential placebo and expectation effects.
While the study had many strengths including being well powered, there were also a number of limitations.
Implications for practice
VRTs certainly have potential, for example, they have been shown to help people with psychosis overcome agoraphobia (Freeman et al., 2022). This technology is potentially a powerful and relatively novel tool for assessing, understanding, and treating mental health problems. However, in services already stretched for time and resources, investing in expensive equipment, software, and therapist training doesn’t seem realistic unless those tools are clearly proven to deliver real, lasting change.
Smith et al. have provided new evidence that an immersive 3D AVATAR VRT for distressing voices can, in theory, be delivered within local mental health services and may be acceptable for some people with schizophrenia. While some early pilot and smaller-scale studies showed promising results, these have not been replicated in the current trial.
AVATAR studies have all produced similar small to medium effects that aren’t maintained after the therapy ends (Garety et al., 2024; Craig et al., 2018). Perhaps it is time to ask how much more should be invested in this area of research, without strong indications that this approach could provide clinically meaningful differences for patients? That is not to diminish the need to develop new, safe and effective interventions given the limited therapies available that make a meaningful difference to recovery, daily functioning, or quality of life for people living with psychosis.
To move beyond the hype and understandable excitement surrounding VR approaches for voices, future research needs to determine whether this approach can truly be effective long-term, safe, and accessible for the diverse communities that need it. This requires more compelling evidence that effectively addresses current limitations in the field.
Statement of interests
I am a Research Assistant working on a trial in a similar area of research, called the Talking with Voices (TwV) II trial. The TwV trial is testing a novel dialogical therapy to find out whether it is effective in improving personal recovery in people who hear distressing voices. I work within the Oxford Cognitive Approaches to Psychosis (O-CAP) research team, which has been conducting trials of immersive VRTs for over 20 years, one of which is referenced in this blog.
Links
Primary paper
Smith, L. C., Vernal, D. L., Mariegaard, L. S., Christensen, A. G., Jansen, J. E., Schytte, G., Stokbro, L. A., Albert, N., Christensen, M. J., Thomas, N., Hjorthøj, C., Nordentoft, M., & Glenthøj, L. B. (2025). Immersive virtual reality-assisted therapy targeting persistent auditory verbal hallucinations in patients diagnosed with schizophrenia spectrum disorders in Denmark: The Challenge assessor-masked, randomised clinical trial. The Lancet Psychiatry, 12(8), 557–567.
Other references
Craig, T. K., Rus-Calafell, M., Ward, T., Leff, J. P., Huckvale, M., Howarth, E., Emsley, R., & Garety, P. A. (2018). AVATAR therapy for auditory verbal hallucinations in people with psychosis: A single-blind, randomised controlled trial. The Lancet Psychiatry, 5(1), 31–40.
Dellazizzo, L., Potvin, S., Phraxayavong, K., & Dumais, A. (2021). One-year randomized trial comparing virtual reality-assisted therapy to cognitive–behavioral therapy for patients with treatment-resistant schizophrenia. NPJ Schizophrenia, 7, 9.
Freeman, D., Lambe, S., Kabir, T., Petit, A., Rosebrock, L., Yu, L.-M., Dudley, R., Chapman, K., Morrison, A., O’Regan, E., Aynsworth, C., Jones, J., Murphy, E., Powling, R., Galal, U., Grabey, J., Rovira, A., Martin, J., Hollis, C., … West, J. (2022). Automated virtual reality therapy to treat agoraphobic avoidance and distress in patients with psychosis (gameChange): A multicentre, parallel-group, single-blind, randomised, controlled trial in England with mediation and moderation analyses. The Lancet Psychiatry, 9(5), 375–388.
Garety, P. A., Edwards, C. J., Jafari, H., Emsley, R., Huckvale, M., Rus-Calafell, M., Fornells-Ambrojo, M., Gumley, A., Haddock, G., Bucci, S., McLeod, H. J., McDonnell, J., Clancy, M., Fitzsimmons, M., Ball, H., Montague, A., Xanidis, N., Hardy, A., Craig, T. K. J., & Ward, T. (2024). Digital AVATAR therapy for distressing voices in psychosis: The phase 2/3 AVATAR2 trial. Nature Medicine, 30(12), 3658–3668.
Leff, J., Williams, G., Huckvale, M., Arbuthnot, M., & Leff, A. P. (2014). Avatar therapy for persecutory auditory hallucinations: What is it and how does it work? Psychosis, 6(2), 166–176.
Percie Du Sert, O., Potvin, S., Lipp, O., Dellazizzo, L., Laurelli, M., Breton, R., Lalonde, P., Phraxayavong, K., O’Connor, K., Pelletier, J.-F., Boukhalfi, T., Renaud, P., & Dumais, A. (2018). Virtual reality therapy for refractory auditory verbal hallucinations in schizophrenia: A pilot clinical trial. Schizophrenia Research, 197, 176–181.
