Metaverse for mental health disorders: Opportunities and challenges

Table 1 Metaverse: Structure and functions[7,9,11,14,15]

Core technologies	Features	Functions
Virtual reality involves immersion of the user in real-life like virtual environments employing headmounted displays, haptic device simulators and computerbased simulations. It creates a sense of presence and allows interaction with the environment	Three-dimensional experience. Virtual environment- non-tangible and digitally created. Immersive experience - complete transportation to and sensory engagement in virtual environments. Multimodal representations, content, and interactions involving all types of sensory stimuli. Interoperable network - the ability of components to work together and exchange information. Multi-user capability - in theory, unlimited number of users. Scalable – ability to expand to meet demands of users. Shared, interactive and collaborative. Decentralized - control lies in the hands of users. Avatars – digital representations of the user, controlled by users. Embodiment – sensing and feeling of ownership of avatars. Real-time - events are portrayed at the same rate at which the characters experience them. Integrity and data security – provided by blockchain technology. “Mirror world” – a virtual world that reflects an expanded version of the real world. “Virtual world” - a metaverse world peopled by avatars that is separate from reality. Fusion of the physical and virtual worlds – real and virtual world actions impact each other. Synchronous experience. Sustainable and persistent experience. Continuity – identity, experience, functions remain the same. “Lifelogging” – captures and shares daily life experiences of users. Individual sense of presence – sense of being there. Socially meaningful content- content that incorporates social values, which promotes user immersion	Basic functions: Socialization - social networking, social connectedness, social influence. Learning – social and other forms of digital learning. Cognitive and physical activation. Emotion regulation. Self-determination – autonomy, self-efficacy, sense of achievement and competence, self-awareness, control of self and environment
Augmented reality superimposes digital information on to the physical world using smartphones, smart glasses, or head-mounted displays. It allows users to interact with virtual objects in the real world
Mixed reality fuses elements from both the physical and digital worlds and allows interactions between these worlds during immersion. It enables greater control over the virtual objects than augmented reality
Extended reality includes virtual, augmented and mixed realities
Artificial Intelligence, machine learning, and big data analysis create dynamic, interactive, and user-responsive environments, predict user behavior, and guide user choices
Blockchain technology refers to secure storage of data in blocks linked together in a chain. The stored information is accessible but cannot be changed		Functions that impact mental health: Stress reduction. Social acceptance and support. Induces positive affect and improves life satisfaction. Improves wellbeing. Improves coping skills. Improves behavioral and social skills. Group interactions improve self-expression, understanding of self and others, communication and social skills
Edge/cloud computing: The process of bringing computation and storage elements closer to the network edge using cloud architecture
Internet of Things refers to the collective network of connected devices and the technology that facilitates communication between these devices and the cloud
Digital twin technology establishes a virtual twin of a real-world object, connects the digital representation to the real object, and predicts the behavior of the real-world object by real-life simulations
Non-fungible tokens are digital certificates of ownership and authenticity for digital or physical assets
Digital economy includes digital wallets and cryptocurrency to carry out secure digital transactions
Fifth generation internet with high bandwidth and low latency enables rapid and secure access and transactions

Table 2 Metaverse-based interventions in psychiatric disorders: Examples

Ref.	Study	Findings
Yellowlees and Cook[28], 2006	Pilot study using the Second Life metaverse platform to simulate auditory and visual hallucinations of patients with schizophrenia. Five hundred seventy-nine users competed the tour and recorded their responses	The majority of users reported that the virtual tour improved their understanding of hallucinations and that they would recommend it for others
Hoch et al[29], 2012	Mindfulness and relaxation-based resiliency training using the Second Life metaverse platform in 24 healthy participants	The intervention was feasible and acceptable to the participants. It led to reduction in stress, depression, and anxiety. The effects were comparable to in-person interventions
Yuen et al[30], 2013	Feasibility, acceptability, and efficacy of an acceptance-based therapy using the Second Life metaverse platform in 14 people with social anxiety disorder	Participants and therapists rated the intervention as feasible and acceptable. The intervention led to improvements in social anxiety, depression, disability, and quality of life
Matsangidou et al[31], 2022	Feasibility trial of a “Multi-User Virtual Reality”-based remote psychotherapy in 13 participants with eating disorders	Feasibility, acceptability, and the usefulness of the application was demonstrated. High levels of immersion and sense of presence were the key to success
Lee et al[32], 2023	Open-label, single-center, pilot parallel randomized controlled trial of 15 children with high-functioning autistic spectrum disorder. Treatment consisted of a metaverse-based social skills intervention delivered via the metaverse platforms (Roblox) and Zoom	The intervention was significantly more effective than the control treatment in improving social interaction, social cognition, social communication, and autistic mannerisms. The intervention enhanced mental health, reduced emotional and behavioral problems in children, and distress among parents
Vila et al[33], 2024	Randomized controlled trial of avatar-based psychotherapy using the Second Life metaverse platform in 31 women with female orgasmic disorder. The intervention consisted of 12 weekly sessions based on cognitive behavioral and acceptance and commitment therapy	Compared to the control group, participants in the avatar-based intervention showed a significant improvement in reduction of a sexual disorder diagnosis, improved sexual satisfaction, sexual function, initiative and sexual communication, and sexual self-esteem, reduced guilt about sex, and sexual anxiety, and enhanced adherence
Vila et al[34], 2024	Qualitative analysis of attitudes to metaverse-based psychotherapy for psychiatric and sexual disorders among 21 participants of either gender	Attitudes towards metaverse-based treatment were favorable for both psychiatric and sexual disorders. The main reason was improved access to psychological treatments through the metaverse