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Recent studies have used spatial reorientation task paradigms to identify underlying cognitive mechanisms of navigation in children, adults, and a range of animal species. Despite broad interest in this task across disciplines, little is known about the brain bases of reorientation. We used functional magnetic resonance imaging to examine neural activity in adults during a virtual reality version of the reorientation task. Three environments that varied in the cues provided were studied: a rectangular room with 4 identical gray walls (Geometry), a square room with 3 gray walls and 1 red wall (Feature), and a rectangular room with 3 gray walls and 1 red wall (Feature + Geometry). Multiple areas within the medial temporal lobe (MTL) showed increased activation when a feature was present compared with when reorientation was based only on geometric cues. In contrast, reliance on geometric cues significantly activated a number of non-MTL structures, including the prefrontal cortex and inferior temporal gyrus. These results provide neural evidence for processing differences between the 2 types of cue as well as insight into developmental and comparative aspects of reorientation. [ABSTRACT FROM AUTHOR]

There are marked individual differences in the formation of cognitive maps both in the real world and in virtual environments (VE; e.g., Blajenkova, Motes, & Kozhevnikov, 2005; Chai & Jacobs, 2010; Ishikawa & Montello, 2006; Wen, Ishikawa, & Sato, 2011). These differences, however, are poorly understood and can be difficult to assess except by self-report methods. VEs offer an opportunity to collect objective data in environments that can be controlled and standardized. In this study, we designed a VE consisting of buildings arrayed along 2 separated routes, allowing for differentiation of between-route and within-route representation. Performance on a pointing task and a model-building task correlated with self-reported navigation ability. However, for participants with lower levels of between-route pointing, the Santa Barbara Sense of Direction scale (Hegarty, Richardson, Montello, Lovelace, & Subbiah, 2002) did not predict individual differences in accuracy when pointing to buildings within the same route. Thus, we confirm the existence of individual differences in the ability to construct a cognitive map of an environment, identify both the strengths and the potential weaknesses of self-report measures, and isolate a dimension that may help to characterize individual differences more completely. The VE designed for diis study provides an objective behavioral measure of navigation ability that can be widely used as a research tool. [ABSTRACT FROM AUTHOR]

The geometry formed by the walls of a room is known to be a potent cue in reorientation, yet little is known about the use of geometric information gleaned from other contexts. We used functional magnetic resonance imaging to examine neural activity in adults while reorienting in 3 different environments: the typical rectangular walled room, a rectangular configuration of pillars in an open field, and a rectangular floor in an open field. Behavioral response patterns for the 3 environments were similar, but pairwise contrasts of brain activation revealed differences at the neural level. We observed greater medial temporal lobe (MTL) involvement when reorienting with the pillars versus the walls and floor. In addition, the walled room selectively engaged areas of posterior parahippocampal cortex corresponding to the parahippocampal place area, when compared with the floor. Finally, a conjunction analysis of the 3 geometry conditions, compared with a control task, revealed activation in the primary auditory cortex that was common to all geometry conditions. These findings add to growing evidence that adults use verbal processes to encode environment geometry and that the reorientation tasks that young children find difficult are particularly hippocampus-dependent. [ABSTRACT FROM AUTHOR]