۱٫۱٫ Virtual Reality for Anatomy Learning.

Virtual reality (VR) aims to provide its users with an illusory environment by completely replacing direct sensory stimuli for artificially generated (or mediated) sensory stimuli. Complete immersion in a virtual environment would enable interaction with virtual objects similar to interaction with real objects [1]. In addition to this, VR allows the development of interaction modalities for which no real-world analog exists. For the study of human anatomy, this promises extraordinary versatility and flexibility in the presentation and exploration of anatomical objects, at a fraction of the cost of maintaining dissection facilities [2–۴]. However, full VR is technologically challenging and has not yet been implemented. The ongoing development of virtual reality is reflected in the lack of consensus in the literature as to the effectiveness of digital 3D representations for human anatomy learning. Older studies often report ambiguous or negative findings (e.g., [5, 6]). These studies however do not utilize the full potential of virtual reality, using 3D computer models in a “desktop VR” setting. In desktop VR, sources of spatial information such as physical size and tactile/force feedback are lost, and there is no direct interaction or sense of sharing space with virtual anatomical objects. Navigating such an environment might add to the cognitive load of the participants experienced during those experiments, which in turn could have biased the results of those studies. This is corroborated by studies working with a more complete implementation of virtual reality principles, which report a positive contribution of virtual reality for anatomy learning (the study of [2] provides a review and meta-analysis; [7, 8]). Despite uncertainty as to its effectiveness, virtual human anatomy has become an integral part of the medical curriculum [9]. 1.2. Stereopsis in Digital Anatomy Learning. Besides the loss of tactile and force feedback, desktop VR anatomy comes with another limitation: the spatial information provided by the visual depth cue of stereopsis is also lost. Stereopsis refers to the experience of spatial depth based on the brain’s comparison of synchronous and overlapping visual information provided by an organism’s paired eyes. Stereopsis is one of the most important depth cues for estimating distance and size for objects in close proximity to oneself ([10]; see also [11]). The loss of spatial information caused by digital mediation makes it harder to interpret spatially complex objects or contexts [12], especially for people of low visuospatial ability [13]. Human anatomy is spatially complex, and people of high visuospatial ability have an advantage in anatomy learning ([14] provides a review).