This systematic review synthesizes evidence on immersive technologies for cognitive rehabilitation across the MCI-dementia continuum, with an explicit focus on usability, therapeutic efficacy, and limitations spanning VR, AR, and CAVE-like embodied systems. Overall, the literature indicates that immersive interventions are feasible and frequently engaging, with signals of benefit across multiple cognitive domains (eg, attention, memory, executive functions, and spatial navigation), but the strength of conclusions remains constrained by substantial heterogeneity in technology, protocols, and outcomes, as well as the predominance of small-sample and early-phase designs.
A key implication is that outcome interpretation cannot be separated from usability and tolerability. In cognitively impaired older adults, interface complexity, onboarding requirements, comfort, and adverse effects can influence adherence and delivered exposure (ie, the effective "dose"), thereby shaping observed performance and functional outcomes. Future studies should therefore treat usability, safety, and acceptability as core outcomes, report them transparently (including adverse events and reasons for withdrawal), and analyze them alongside cognitive and functional measures.
For the next generation of research, priorities include (1) clearer specification and reporting of intervention components (tasks, feedback, progression, and supervision), (2) better alignment of outcomes with clinically meaningful goals, including functional end points (ADL or IADL) and quality-of-life measures, (3) adequately powered comparative trials with well-justified control conditions, and (4) explicit evaluation of implementation and scalability, particularly for home and community deployment. Advancing methodological standardization and reporting consistency will be essential to enable cumulative synthesis and to support translation of immersive cognitive rehabilitation into dependable, real-world care pathways across the MCI-dementia continuum.
