The assessment of non visual maritime cognitive maps of a blind sailor: a case study

Please click here to download the map associated with this article. Nowadays, thanks to the accessibility of GPS, sighted people widely use electronic charts to navigate through different kinds of environments. In the maritime domain, it has considerably improved the precision of course control. In this domain, blind sailors can not make a compass bearing, however they are able to interact with multimodal electronic charts. Indeed, we conceived SeaTouch, a haptic (tactilekinesthetic) and auditory virtual environment that allows users to perform virtual maritime navigation without vision. In this study we attempt to assess if heading or northing "haptic" views during virtual navigation training influences non-visual spatial knowledge. After simulating a navigation session in each condition, a blind sailor truly navigated on the sea and estimated seamark bearings. We used the triangulation technique to compare the efficiency of northing and heading virtual training. The results are congruent with current knowledge about spatial frames of reference and suggest that getting lost in heading mode forces the blind sailor to coordinate his current "view" with a more global and stable representation.