Usability and Cognitive Impact of the Interaction with 3D Virtual Interactive Acoustic Environments by Blind Children

It is known that blind children represent spatial environments with cognitive difficulty. This can be decreased if they are exposed to interactive experiences with acoustic stimuli delivered through spatialized sound software. A few studies have approached this issue by using interactive applications that integrate virtual reality and cognitive tasks to enhance spatial orientation skills. The aim of this research was to implement a field study to detect and analyze cognitive and usability issues involved in the use of an aural environment and the issues of representing navigable structures with only spatial sound. This experimental study has arisen from a challenging pilot research project to a full fledged field-testing research with eleven children during six months in a Chilean school for blind children. The research was implemented by using a kit of cognitive representation tasks, which includes exposure to the 3D acoustic environment, corporal exercises, and experiences with concrete representation materials such as sand, clay, storyfoam, and Lego bricks. The cognitive kit also included activities to represent the perceived environment, the organization of the space, and problem solving related to the interactions with the software. The usability testing of the environment was an explicit issue in the research by using both qualitative and quantitative methods including interviews, survey methods, logging actual use, still pictures, and video tape recording session analysis. The idea was to motivate and engage blind children to explore and interact with virtual entities in challenge-action software and to construct invisibly cognitive spatial mental representations. The results of the study revealed that blind children can achieve the construction of mental structures rendered with only 3D sound and that spatial imagery is not purely visual by nature, but can be constructed and transferred through spatialized sound. Our hypothesis was fully confirmed revealing that each blind child passes four clear stages in their interaction with the sound environment and performing cognitive tasks: entry, exploration, adaptation, and appropriation. We also conclude that the child possesses both unique skills and pace referred to mental and spatial development, impacting directly on the quality of the topological features obtained in comparison to the ideal reference spatial structure embedded in the software.