Virtual Reality Full Immersion Techniques for Enhancing Workers Performance, 20 years Later: A Review and a Reformulation <s> C. Immersion <s> In this paper, I address the question as to why participants tend to respond realistically to situations and events portrayed within an immersive virtual reality system. The idea is put forward, based on the experience of a large number of experimental studies, that there are two orthogonal components that contribute to this realistic response. The first is ‘being there’, often called ‘presence’, the qualia of having a sensation of being in a real place. We call this place illusion (PI). Second, plausibility illusion (Psi) refers to the illusion that the scenario being depicted is actually occurring. In the case of both PI and Psi the participant knows for sure that they are not ‘there’ and that the events are not occurring. PI is constrained by the sensorimotor contingencies afforded by the virtual reality system. Psi is determined by the extent to which the system can produce events that directly relate to the participant, the overall credibility of the scenario being depicted in comparison with expectations. We argue that when both PI and Psi occur, participants will respond realistically to the virtual reality. <s> BIB001 </s> Virtual Reality Full Immersion Techniques for Enhancing Workers Performance, 20 years Later: A Review and a Reformulation <s> C. Immersion <s> We studied two interactive (functional and intentional interactivity) and immersive (technical and psychological immersion) devices with a personal 3D viewer (360° vision and environmentally ego-centered) and their effects on the explicit long-term memories of the subjects (4 groups of 30 students for a total of 120 subjects) (2007 and 2012). We have tested memory, communication and feeling of presence in our virtual environment with a canonic test of presence (Witmer and Singer, 1998). In our first experiment (2007), the results showed that there was no improvement in mnemonic performances compared with other types of media (PowerPoint classes without taking notes, with the taking of notes and a lecture class with no other medium). Our second experiment (2012) used a total-immersion device with the ability for the subjects to share their emotions and sensations through a network, results in progress). This article is a reflection on immersion and the presence sensation in a virtual environment in these 3D devices. <s> BIB002
This is a feature of VR in which users are in a simulated environment. An immersive VR system seeks the user to lose contact with reality by exclusively perceiving the stimuli of the virtual world. However, the immersion achieved so far in VR systems is restricted only to spatial immersion; that is, the perception of being physically present in a virtual world  . Psotka  , states that the fact that a user is in a simulated virtual environment has a huge emotional factor that facilitates cognition and improves information retention, because the user feels that they are part of software. In addition, immersion broadens the user's range of vision, including their displace- Slater BIB001 distinguishes two ways of experiencing immersive VR: an HMD VR helmet (acronym for head-mounted display) and a three-dimensional cave-like environment . For this purpose, immersion has been achieved through different configurations, for example, a single giant screen may be used as well as anaglyph lenses. Another configuration is that of a CAVE environment, which consists of four or 6 walls of almost 3m3, which function as stereo projection screens. The images are determined as a head tracking function so that, at least with respect to the visual system, participants can physically move through a limited space and orient their head arbitrarily to be able to perceive. Usually, the audio is delivered by a set of speakers in discrete positions around the CAVE  . In this investigation, the immersion will be used based on a VR helmet, which is one of the most comfortable compared to the others and because it gives a greater sense of presence that helps memory and other cognitive processes BIB002 . But one of the main drawbacks of this configuration is that it can cause dizziness in certain users.