Impact of CAVE automatic virtual environment (CAVE) on user experience and health outcomes: A systematic review

Many virtual reality systems, including the fully immersive Cave Automatic Virtual Environment (CAVE), have been developed over the years. Although CAVE has been used primarily in domains such as research, training, and visualisation, its application in therapeutic interventions has also been explored. However, the extent to which specific characteristics of CAVE shape user experience and contribute to measurable health outcomes, including motor function, psychological well-being, and cognitive performance, in neurological, developmental and psychiatric conditions requires further review.

This review aims to identify CAVE's characteristics and to synthesise the user experience and health outcomes reported for interventions delivered through these systems in neurological, developmental, and psychiatric conditions.

Eligible studies were sourced across six electronic databases, grey literature, trial registries, and hand-searching from 2014 to October 2024. Randomised controlled trials and quasi-experimental studies were eligible. Because of substantial heterogeneity in populations, system configurations, intervention content, and outcome measures, meta-analysis was not appropriate and a narrative synthesis was conducted. A narrative synthesis was conducted. Quality appraisal was conducted using Cochrane's Risk of Bias (RoB) tool and Joanna Briggs Institute (JBI) Checklist for Quasi-Experimental Studies.

Fifteen studies (552 participants) were analysed, and most were appraised as moderate quality. Interventions were delivered through CAVE systems for diverse age groups, including children aged 6 months to 14 years, adults aged 18 and older, and older adults over 60. Interventions delivered through CAVE were associated with improvements in gait and balance in most studies, whereas findings for psychological well-being and cognitive function were drawn from a small number of small, heterogeneous studies and were inconsistent. Where user experience was assessed (four studies), participants generally described the environment as enjoyable and reported few side effects such as cybersickness, although one study rated presence and involvement lower than with a head-mounted display (HMD).

Interventions delivered through CAVE systems have demonstrated preliminary evidence of improving clinical outcomes in users with neurological, developmental, and psychiatric conditions. However, the current evidence base is small, heterogeneous in system configuration and intervention content, and largely of moderate quality. Compared to HMDs, CAVE systems may offer a less isolating experience due to their open, projection-based design. However, evidence on relative immersion is mixed. The risk of cybersickness appeared low across most included studies, though this varied by system design and participant population. Adequately powered trials, together with further development of CAVE for portability and group therapy, are needed to establish effectiveness and optimise scalability.