Medical assessment test of extrapersonal neglect using virtual reality: A preliminary study

The research work presents a preliminary study to create a virtual reality platform for the medical assessment of spatial extrapersonal neglect, a syndrome affecting human awareness of a hemi-space that may be caused by cerebral lesions. Nowadays, the extrapersonal neglect is assessed by using real objects positioned in the space around the patient, with a poor capability of repetition and data gathering. Therefore, the aim of this research work is the introduction of a virtual reality solution based on consumer technology for the assessment of the extrapersonal neglect. By starting from the needs of the involved medical personnel, an online serious-game platform has been developed, which permits to perform a test and a real-time evaluation by means of objective data tracked by exploited technologies, i.e. an HTC Vive Pro head mounted display and ad-hoc IT solutions. The test is based on a virtual environment composed by a table on which twenty objects have been placed, ten on the right side and ten on the left side. The whole 3D virtual environment has been developed using low-cost and free development tools, such as Unity and Blender. The interaction with the virtual environment is based on voice recognition technology, therefore the patient interact with the application by pronouncing the name of each object aloud. The VR application has been developed according to an online gaming software architecture, which permits to share the 3D scene by exploiting a Wi-Fi hotspot network. Furthermore, the on-line gaming software architecture allows sending and receiving data between the doctor's laptop and the VR system used by the patient on another laptop. The therapist can see through his/her personal computer a real time faithful replica of the test performed by the patient in order to have a fast feedback on patient’s field of view orientation during the evaluation of 3D objects. A preliminary test has been carried out to evaluate the ease of use for medical personnel of the developed VR platform. The big amount of recorded data and the possibility to manage the selection of objects when the voice commands are not correctly interpreted has been greatly appreciated. The review of the performed test represents for doctors the possibility of objectively reconstructing the improvements of patients during the whole period of the rehabilitation process. Medical feedback highlighted how the developed prototype can already be tested involving patients and thus, a procedure for enrolling a group of patients has been planned. Finally, future tests have been planned to compare the developed solution with the Caterine Bergero Scale to define a future standardization.