When your border and my border differ: Spatial regionalisation and route choice depends on perceived landmark categorization

Humans spontaneously structure spatial environments into a hierarchy of regions. Besides connectivity and boundaries, sensory or functional similarities of landmarks have been shown to influence construction of regions. In natural spaces, regions and places are usually named and these names provide additional cues for the cognitive construction of regions. In this study we investigate the role of semantic similarities of place names in the formation of regions in a virtual environment with homogeneous connectivity. Place names were selected and distributed in a way that two alternative semantic categorizations were possible which corresponded to two equally valid regionalisations of the same environment. Region perception was assessed by having subjects choose between two equidistant routes crossing different numbers of region boundaries (classification consistent route choice). In a priming phase, subjects were biased to sort the landmark names in one or the other categorization scheme. In the test phase, subjects preferably selected routes with a lower number of region crossings according to the categorization previously discovered. The results show that perceived semantic similarity of place names does affect route choice and the formation of spatial regions.