Seeing the world by hearing: Virtual Acoustic Space (VAS) a new space perception system for blind people.

Virtual Acoustic Space (VAS) is a research and development project on the perception of space using only sound. A portable electronic prototype that allows blind people to receive spatial information of their surroundings has been developed. This information is perceived via an audible image using Head Related Transfer Function (HRTFs) processed sounds. The main goal is to create for the user the illusion that the surrounding objects are covered by small sound continuously emitting sources in a particular and sustained way. Therefore, a virtual acoustic world is generated, where a physical object emit sounds from all the coordinates of its surface. Our results validate the hypothesis that, it is possible to generate an experience of global and sustained presence of different objects inside the perception field from these stimuli, with the same shape, dimensions and location as the real environment. Our objectives are now focused on: a better delimitation of the observed capabilities, the study of the developed prototype in everyday life conditions, on exploring how blind people learn to use new strategies to improve their perception of the environment and the exploration of the possible cortical brain areas involved in this process, using functional imaging techniques