Virtual Reality Interface Built Using Unity3D for Rehabilitation with BCI Systems Based on Motor Imagery

摘要

An approach to rehabilitation therapy of stroke patients is to promote neuronal plasticity by providing users with information that allows them to re-learn motor skills. To this mean, systems combining Brain Computer Interface based on motor imagery (MI-BCI) with virtual reality (VR) have been developed. These systems translate the user's motor intention detected in the electroencephalography recording into a control signal, which activates a feedback module. This module should provide patients with visual feedback in realtime immersive environments, in order to motivate them during therapy and make them feel part of the virtual environment. This article describes the design and development of a VR interface, which could be used as visual feedback in a MI-BCI system during the upper and lower limbs rehabilitation of stroke patients. In order to design the VR feedback interface, characteristics that would promote the patients neuronal plasticity were considered: (a) a motivating and attractive VR interface presenting an avatar that resembles to the patient; (b) the possibility of executing functional tasks related to the skills that need to be rehabilitated; (c) real time communication between the user and the virtual environment. In addition, technical design requirements were considered: (a) real time communication between the MI-BCI system and the VR interface; (b) a VR interface that could be used in a computer device with limited resources. As a result, the VR interface, which was developed using Unity3D and satisfied the design requirements, is presented.