Mapping the Evolutions and Trends of Literature on Wayfinding in Indoor Environments

Research on indoor wayfinding has increased in number and significance since the 1980s. Yet, the information on wayfinding literature is now difficult to manage given its vast scope and spread across journals, institutions, disciplines, and themes. While there is an increasing number of publications within this rapidly growing field of research, there are limited review studies in the field, and there is still missing an overall analysis of the current state of wayfinding literature and its evolution. The main objective of this study is to present a bibliometric analysis of about forty years of research on indoor wayfinding to provide an overview of the research landscape. The final database of the study contained 407 publications. VOSviewer was used as a science mapping software tool to identify major focus areas and to identify influential authors, publications, and journals using various network analysis techniques, such as term co-occurrence, co-citation, and bibliographic coupling. Similar co-occurrence analysis was used to understand how the intellectual base of the field has evolved over time and what the major themes are that have contributed to this evolution. The results show that this field has initially been mainly focused on few themes but has later become more diversified to acknowledge the multi-dimensional characteristics of indoor wayfinding. While spatial knowledge acquisition and cognitive maps are still dominant core areas, there are topics, such as signage, isovists, and the use of eye-tracking and virtual reality, that still need to be further investigated.

Age-Related Changes in Spatial Navigation Are Evident by Midlife and Differ by Sex

Accumulating evidence suggests that distinct aspects of successful navigation—path integration, spatial-knowledge acquisition, and navigation strategies—change with advanced age. Yet few studies have established whether navigation deficits emerge early in the aging process (prior to age 65) or whether early age-related deficits vary by sex. Here, we probed healthy young adults (ages 18–28) and midlife adults (ages 43–61) on three essential aspects of navigation. We found, first, that path-integration ability shows negligible effects of sex or age. Second, robust sex differences in spatial-knowledge acquisition are observed not only in young adulthood but also, although with diminished effect, at midlife. Third, by midlife, men and women show decreased ability to acquire spatial knowledge and increased reliance on taking habitual paths. Together, our findings indicate that age-related changes in navigation ability and strategy are evident as early as midlife and that path-integration ability is spared, to some extent, in the transition from youth to middle age.

Embodied Spatial Knowledge Acquisition in Immersive Virtual Reality: Comparison to Map Exploration

Investigating spatial knowledge acquisition in virtual environments allows studying different sources of information under controlled conditions. Therefore, we built a virtual environment in the style of a European village and investigated spatial knowledge acquisition by experience in the immersive virtual environment and compared it to using an interactive map of the same environment. The environment was well explored, with both exploration sources covering the whole village area. We tested knowledge of cardinal directions, building-to-building orientation, and judgment of direction between buildings in a pointing task. The judgment of directions was more accurate after exploration of the virtual environment than after map exploration. The opposite results were observed for knowledge of cardinal directions and relative orientation between buildings. Time for cognitive reasoning improved task accuracies after both exploration sources. Further, an alignment effect toward the north was only visible after map exploration. Taken together, our results suggest that the source of spatial exploration differentially influenced spatial knowledge acquisition.

Toward a Subject-Independent EEG-Based Neural Indicator of Task Proficiency During Training

This study explores the feasibility of developing an EEG-based neural indicator of task proficiency based on subject-independent mental state classification. Such a neural indicator could be used in the development of a passive brain-computer interface to potentially enhance training effectiveness and efficiency. A spatial knowledge acquisition training protocol was used in this study. Fifteen participants acquired spatial knowledge in a novel virtual environment via 60 navigation trials (divided into ten blocks). Task performance (time required to complete trials), perceived task certainty, and EEG signal data were collected. For each participant, 1 s epochs of EEG data were classified as either from the “low proficiency, 0” or “high proficiency, 1” state using a support vector machine classifier trained on data from the remaining 14 participants. The average epoch classification per trial was used to calculate a neural indicator (NI) ranging from 0 (“low proficiency”) to 1 (“high proficiency”). Trends in the NI throughout the session—from the first to the last trial—were analyzed using a repeated measure mixed model linear regression. There were nine participants for whom the neural indicator was quite effective in tracking the progression from low to high proficiency. These participants demonstrated a significant (p < 0.001) increase in the neural indicator throughout the training from NI = 0.15 in block 1 to NI = 0.81 (on average) in block 10, with the average NI reaching a plateau after block 7. For the remaining participants, the NI did not effectively track the progression of task proficiency. The results support the potential of a subject-independent EEG-based neural indicator of task proficiency and encourage further research toward this objective.

Landmark-Based Turn-by-Turn Instructions Enhance Incidental Spatial Knowledge Acquisition

The augmentation of landmarks in auditory navigation instructions had been shown to improve incidental spatial knowledge acquisition during assisted navigation. Here, two driving simulator experiments are reported that replicated this effect even when adding a three-week delay between navigation and spatial tasks and varying the degree of detail in the provided landmark information. Performance in free- and cued-recall of landmarks and driving the route again without assistance demonstrated increased landmark and route knowledge when navigating with landmark-based compared to standard instructions. The results emphasize that small changes to existing navigation systems can foster spatial knowledge acquisition during every-day navigation.