Spatial Perception Under Visual Prosthetic Vision

In the research direction of artificial vision,as a research hotspot,visual prosthesis has played an important role in the development of visual recovery and the study of visual pathways.It brings the gospel to the rehabilitation of the blind.By stimulating surviving neurons,signals are transmitted to the visual center,which induces photophantoms in the visual center,thereby generating artificial vision.Close-space perception is very important for target location,guidance and navigaion of various daily activities(walking,obstacle avoidance).Spatial perception is an important research direction to explore the effectiveness of visual prostheses.At present,the research on spatial perception under simulated prosthetic vision has not achieved relatively effective results.By studying the effect of prosthetic vision on spatial cognition,the research results can help visual prostheses to find out the current problems of visual prostheses and facilitate.The design of the visual prosthesis has made some improvements and optimizations,and it also provides data support and theoretical guidance for the rehabilitation training of future implant implanters.In this paper,whether the perception of spatial stereo vision by the wearer of the prosthesis is affected by performing monocular ranging experiments and speed measurement tasks under simulated prosthetic vision were analyzed.Firstly,the monocular distance measurement experiment under simulated prosthetic vision was carried out in a real scene.The experiment uses blindfold ranging method.Participants weared head-mounted displays to simulate and visualize target objects placed on different positions on the floor(3.51 m,4.92 m,6.33 m)under the three visual conditions of the simulated prosthetic monocular,the simulated prosthetic eyes,and the normal monocular.Then they walked blindly to the place he / she judges by blindfolding.The walking distance were recorded and statistically analysed.The experimental results showed that under three observation conditions,the normal monocular perception accuracywas the highest,and the artificial prosthesis perception accuracy was the lowest.As the distance the object increased,the accuracy also decreased slightly.Statistical analysis of experimental data found that there was no significant difference in distance judgment between the simulated prosthesis monocular and normal monocular observation conditions.It is indicating that the implantation of the prosthesis had no significant effect on the distance judgment of objects placed on the ground.Secondly,a study of speed measurement tasks under simulated prosthetic vision was performed.A virtual model was constructed through Unity 3D.The uniformly moving ball passed through a block of a fixed distance,the subject was allowing to estimate the time of passing time and the distance.The estimated time were recorded.By comparing the estimated time and the actual passing time under the vision of the artificial prosthesis,it is is verified whether the speed perception ability still exists in the prosthesis implanter and the relationship between the strength of the speed perception ability and other factors.The experimental results showed that the speed perception ability of the prosthesis implanter still exists,and the increase of the speed of the moving object could also lead to the improvement of the estimation accuracy.The change in the width of the obstruction has no significant difference in the impact on speed perception.