Moving Towards and Reaching a 3-D Target by Embodied Guidance: Parsimonious Vs Explicit Sound Metaphors

Sensory Substitution Devices (SSDs) assist Visually Impaired People (VIP) by providing information usually acquired vision through another functional sensory modality. Here, we evaluate a SSD that aims to guide visually impaired people target converting spatial into sound. A balance must be struck between parsimonious and explicit guidance, so it is precise but not imposing an excessive cognitive load. express the deviation from participant’s hand. We compared three sound metaphors: 1) Binary (BI) gives only right direction white noise, 2) Angle-to-Pitch (AP) converts 3-D angular pointed pitch according continuous function, 3) Dissociated Vertical-Horizontal (DVH) dissociates two dimensions, using provide projected on horizontal plane (a metaphor) superimposed noise indicate height binary metaphor). conducted “hot cold game” type tests in environment. Participants, with eyes closed, moved search reach virtual spheres their index finger. Each metaphor was evaluated time taken target, questionnaire. The results show advantage of AP over BI: allowed faster hit considered easier use, more efficient, comfortable than BI. They also DVH AP: times were shorter, use AP. good trade-off (use information) (dissociation axes) guidance. It first step towards smartphone SSDs applications help find objects situation visual impairment.