Virtual Reality Relaxation for Insomnia

The objective of this study is to evaluate the feasibility and acceptability of a virtual-reality relaxation intervention for individuals with insomnia disorder, and to assess its effects on pre-sleep arousal, sleep quality, mental health, and sleep depth. The intervention is expected to lead to high feasibility and acceptability, a reduction in cognitive and somatic pre-sleep arousal, a decrease in sleep latency, wake after sleep onset, and number of awakenings, as well as an increase in sleep efficiency. Reductions in insomnia severity, anxiety symptoms, and depressive symptoms are also expected. In addition, variables derived from the Odds Ratio Product (ORP)-a validated index of sleep depth ranging from 0 (deep sleep) to 2.5 (wake)-will be computed. It is anticipated that the intervention will increase the total time spent in deep sleep (ORP 0-0.5) and decrease gamma power (\>35 Hz), alpha intrusion (i.e., the number of three-second epochs with alpha power \> 30 µV²), and the time required for sleep depth to recover following an awakening (ORP-9).

An open-label, parallel-group, randomized controlled trial will be conducted to evaluate the feasibility, acceptability, and efficacy of the intervention. Thirty participants (15 women) aged 25 to 50 will be recruited following a diagnostic interview for insomnia (EDI-A) and psychiatric disorders (MINI). Insomnia severity (ISI), somatic and cognitive arousal (PSAS), and symptoms of anxiety (BAI) and depression (BDI-II) will be assessed using validated questionnaires. Participants will complete a daily sleep diary, and the Prodigy 2 Sleep Monitor, which enables home-based polysomnography (PSG), will be used to assess sleep quality and sleep depth. Feasibility outcomes (recruitment, retention, and adherence) and acceptability of the intervention, assessed through a self-reported questionnaire based on the Theoretical Framework of Acceptability, will complement the study measures.

The virtual-reality intervention consists of a 15-minute guided meditation adapted for sleep and combined with slow breathing (\~6 breaths per minute) to promote immersive relaxation. Sessions will be performed in a seated position before bedtime, aligned with each participant's usual sleep schedule. The guided meditation, developed in collaboration with the McGill Mindfulness Research Lab, aims to enhance present-moment awareness and reduce negative sleep-related thoughts. The immersive environment was created in partnership with OVA, a Quebec-based company specializing in relaxing immersive environments, using visuals (starry night), ambient neutral soundscapes, and gender-neutral, accessible narration. Immersion will be delivered using a Meta Quest 3 headset configured to minimize exposure to blue light.

After providing informed consent and completing the diagnostic interview, eligible participants will complete psychological questionnaires, a two-week sleep diary, and four nights of home PSG at baseline \[T1\]. Participants will then be randomly assigned to the intervention group or the waitlist control group. The intervention group will complete the daily VR intervention for four weeks, after which both groups will undergo a second assessment \[T2\]. The waitlist group will then receive the VR intervention for four weeks, followed by its own post-intervention assessment. A three-month follow-up assessment will be conducted for both groups to evaluate whether the effects of the intervention are sustained over time.

• Insomnia severity [Срок оценки: Baseline (Day 1), end of intervention (Week 4), and 12 weeks after end of intervention (Week 16).]
• Anxiety [Срок оценки: Baseline (Day 1), end of intervention (Week 4), and 12 weeks after end of intervention (Week 16).]
• Depression [Срок оценки: Baseline (Day 1), end of intervention (Week 4), and 12 weeks after end of intervention (Week 16).]
• Sleep health [Срок оценки: Baseline (Day 1), end of intervention (Week 4), and 12 weeks after end of intervention (Week 16).]
• Positive and negative emotions [Срок оценки: Baseline (Day 1), end of intervention (Week 4), and 12 weeks after end of intervention (Week 16).]
• Sleep characters recorded by sleep diary [Срок оценки: Baseline (Day 1), intervention (Weeks 1-4), end of intervention (Week 4), and 12 weeks after end of intervention (Week 16).]
• Sleep characters recorded by a portable sleep monitor [Срок оценки: Four consecutive nights at baseline and four consecutive nights at the end of the intervention (Week 4).]