This was the seminal paper showing that spatialized audio is less effected by increased working memory demands than spatial language when being guided along routes without vision. This finding speaks to the importance of perceptual vs. cognitively mediated nonvisual interfaces. It also showed the efficacy of a new type of secondary working memory task, namely a Vibrotactile N-back task, where participants had to monitor vibrations from three finger stimulators as they performed the route guidance task (see Klatzky et al., 2008 (above) for more on this Vibrotactile N-back paradigm).