# High-Functioning Autism and Virtual Reality Applications: A Scoping Review
### Immersive VR: Technology Overview and Potential  
ASD is a lifelong condition [15]; although there is no particular accepted treatment for ASD, a growing consensus on behavioral and educational intervention programs is flourishing [16], and technology might offer useful solutions. Virtual reality (VR) is one of the emerging and most promising technologies for interventions in healthcare [17] and for training, education, and support for ASD individuals, particularly in children [18]. VR can be defined as a three-dimensional (3D) computer-simulated environment [19], incorporating visual, auditory, and sometimes haptic feedback [20]. According to [PERSON] and colleagues, VR can be classified into three categories [21]: non-immersive, semi-immersive, and fully immersive systems. The level of immersion refers to the extent to which the displays are extensive and able to surround the user, stimulating the senses [22]. The more extensive the displays, the more the user's sensory systems are accommodated [22; 23]. Higher levels of immersion might lead to an increased sense of presence [24], defined as the psychological consequence of immersion [23]. Non-immersive systems are desktop-based (e.g., PC or tablet) and use joypads or keyboards for interaction. Semi-immersive systems consist of large screens or surface projections with moderate levels of immersion and interaction. Lastly, immersive systems comprise Head-Mounted Displays (HMDs) and Cave Automatic Virtual Environment (CAVE) systems, both enabling high levels of interaction and immersion [21]. HMD devices include a head motion tracking system that generates two graphical displays, one for each eye, according to the user's point of view. HMDs are rapidly growing as a consumer product [25], as they are becoming more affordable and easier to use. Several products are available on the market, both for gaming and for educational and training purposes [25]. CAVE technology consists of a four-screen room (three walls and a floor) equipped with four stereoscopic projectors, a tracking system, and stereoscopic glasses provided with markers to change the point of view in VR accordingly [26; 27]. In recent years, the number of applications of VR for the ASD population has escalated [16; 28; 29], and VR has become one of the most suitable tools for addressing the psychological needs of individuals with ASD [16]. This is because of the possibility of practicing in a safe and controlled environment endowed with higher degrees of realism, making VR interventions or assessments more enjoyable and clinical outcomes more reliable and transferrable in the real world [30]. The majority of the studies on ASD and VR focus on strategies to learn and practice social skills [28; 31; 32]. A recent scoping review [33] discusses the use of VR- and augmented reality (AR)-based social interventions for ASD individuals, outlining that there are still gaps to be addressed. Among these, limits include the paucity of studies with HMDs, the methodological lack of rigorous design, and the scarce number of participants enrolled in the experimental studies. Alongside social skills, life skills (e.g., shopping, driving, and street crossing) have also been found to be worthy of VR training applications [16; 18] given the fact that these real-world scenarios might be challenging for ASD individuals. To date, several reviews have been conducted to evaluate VR technology as a support for individuals with ASD. Due to the pervasive difficulties in the social domain, [PERSON] and [PERSON] reviewed the potential of VR in social skills training, outlining some perspectives on the most common interventions [34]. In 2013, [PERSON] conducted a review of single-user virtual environments to teach social communication skills [35]. [PERSON] and colleagues provided a state-of-the-art review about immersive VR as a learning tool for ASD students [31], resulting in social or emotional skills as the most targeted ones.