## 2 Literature Review and Theoretical Framework  
### Perceived Immersion  
The concept of immersion is frequently regarded as the objective level of sensory fidelity offered by a VR system [43; 44]. However, when perceived as a subjective experience, it reflects the extent to which the user feels physically (sensory) and mentally absorbed in the virtual world experience [35; 36; 45]. This paper focuses exclusively on subjectively perceived immersion, utilising the term immersion defined by [46]: \"a psychological state characterised by perceiving oneself to be enveloped by, included in, and interacting with an environment that provides a continuous stream of stimuli and experiences\". Though perceived immersion and presence are often used as having the same meaning and origin, the latter is associated with a psychological state in which users recall virtual reality experiences as though they occurred in reality (e.g., [47; 48]).  
The influence of perceived immersion on various attitudinal, behavioural and experiential constructs has been extensively studied in the context of Educational Virtual Environments [20; 24; 35; 49]. The empirical findings of different studies suggest that when evaluated as a subjective experience, immersion can serve as a significant predictor of various outcomes, including attitudes toward perceived learning benefits [36; 37; 49], future intentions to engage with VR technology [35], and overall satisfaction [38; 45].  
For instance, ref. [36] utilised immersive virtual field trips for science learning to investigate the relationship between students' perceived immersion and the advantages of VR learning. They categorised perceived immersion into basic attention, temporal dissociation, transportation, emotional involvement, and enjoyment, observing that students' immersive experiences, such as their level of attention, positively predict their attitudes towards VR-based learning.  
Employing Structural Equation Modelling (SEM) [35] examined the associations between self-efficacy, perceived immersion, and intention to use VR training systems among high school students in Western China. Among others, they discovered that the student's intention to use VR training systems in the future was directly affected by the quality of the immersion experience.  
The study [37] applied a constructivist approach to understanding university students' behaviour when engaged in a VR learning environment. Their research findings indicated a positive correlation between perceived immersion and students' problem-solving capability, collaborative learning, and the intention to utilise VR technology in the future.  
Using a flow-based conceptualisation of immersion, ref. [45] found that the experience quality (i.e., satisfaction) with VR technology is directly linked to the perceived immersion experiences, indicating that immersion, viewed as a subjective experience, stands as a reliable element in understanding users' overall experience in the context of VR-based learning.  
Similarly, ref. [38] investigated the potential of VR technology for environmental education at the Marine Life Center in the West of France. They discovered that perceived immersion played a significant role in shaping visitors' experience quality and future behavioural intentions (e.g., recommending VR to others).