| Successful navigation generally requires an accurate spatial representation of the environment. However, under guided navigation (i.e. route directions are provided by a GPS system or car passenger) no detailed representation of space is necessary because one only needs to follow directions. The first experiment separated components of navigation, spatial decision-making (planning and selection of routes) and navigational control (executing complex actions such as stopping and steering) for environmental learning. Spatial knowledge was assessed using multiple measures (spatial updating using immersive, head-mounted virtual reality and map construction). More accurate environmental knowledge was acquired when spatial decision-making was present at learning, ps < .001, ds > .81. No difference in spatial knowledge was found between active navigation and spatial decision-making by itself, ps > .83, ds < .07. This finding indicates that the weakened spatial knowledge with control alone (guided navigation) can be explained by the absence of spatial decision-making. Experiments 2 and 3 investigated the use of aids for ameliorating the loss of spatial knowledge for guided navigation with auditory directions. In Experiment 2, guided navigation was augmented using visual aids (primarily egocentric) which reinforced the locations of landmarks. In Experiment 3, guided navigation was augmented by adding cardinal directions (e.g. north), which are exocentric, to the auditory guidance, presented either with monaural sound or stereo sound which corresponded to environmental headings. Spatial knowledge in Experiments 2 and 3 was assessed using route replication, novel route execution, and map construction. Contrary to the hypotheses, the aids did not improve all measures of environmental knowledge. Instead, there was a match between the particular reference frame reinforced by the aid and the relevant frame of reference for the measure of spatial knowledge. In Experiment 2, the visual aids improved accuracy for replicating routes, p = .01, d = .75, this measure is egocentric. In Experiment 3, the stereo and monaural cardinal directions improved accuracy for executing a novel route, a directional measure of survey knowledge, ps < .06, ds > .52, which is egocentric and exocentric. |
