Neurofunctional correlates of geometry and feature use in a virtual environment.

There are mixed results regarding the differentiation of neurofunctional correlates of spatial abilities. Previous studies employed complex environments or alternate memory tasks which could potentially add to inconsistencies across studies of navigation. To help elucidate the existing mixed findings, we conducted a study in a simplistic environment without a supplemental memory task in order to examine navigationally relevant neural function using fMRI. Participants completed a virtual navigation task where they learned the relationship between landmarks, environmental features, and a goal. The goal was a distinct landmark, or feature, consistently situated in one corner, or a geometric cue, of a rectangular room. Test trials varied the relationship of featural and geometric cues allowing insight into navigational strategies when using these cues and when the cues are in conflict. Behavioral results showed participants learned the task rapidly and utilized both landmark feature-based and environmental geometry-based strategies to locate the goal; preferring the feature-based strategy. Neuroimaging results provided evidence for activation in navigationally relevant regions, including the parahippocampus, caudate, and retrosplenial cortex. These results demonstrate the importance of these structures and their relation to environmental geometry and feature use while navigating an enclosed simplistic environment. The results provide clarification regarding the role of the parahippocampus and caudate when using geometric- or landmark-based strategies and demonstrate the prerequisite of environmental novelty to elicit hippocampal activation. (PsycINFO Database Record (c) 2018 APA, all rights reserved).