Spatial navigation by congenitally blind individuals

Abstract

Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our understanding of spatial knowledge acquisition by blind individuals, including their abilities, strategies, and corresponding mental representations. In this review, we propose a framework for investigating differences in spatial knowledge acquisition by blind and sighted people consisting of three longitudinal models (i.e., convergent, cumulative, and persistent). Recent advances in neuroscience and technological devices have provided novel insights into the different neural mechanisms underlying spatial navigation by blind and sighted people and the potential for functional reorganization. Despite these advances, there is still a lack of consensus regarding the extent to which locomotion and wayfinding depend on amodal spatial representations. This challenge largely stems from methodological limitations such as heterogeneity in the blind population and terminological ambiguity related to the concept of cognitive maps. Coupled with an over-reliance on potential technological solutions, the field has diffused into theoretical and applied branches that do not always communicate. Here, we review research on navigation by congenitally blind individuals with an emphasis on behavioral and neuroscientific evidence, as well as the potential of technological assistance. Throughout the article, we emphasize the need to disentangle strategy choice and performance when discussing the navigation abilities of the blind population. For further resources related to this article, please visit the WIREs website.

Figure 1

Four possible outcomes of studying the interaction between spatial strategies and performances in spatial tasks. The two left cells lead to inconclusive or uninterpretable results with respect to the abilities of the blind and sighted. Future research should focus on the outcomes in the two right cells.

Figure 2

Three models of differences in spatial knowledge acquisition between blind and sighted individuals. On the x‐axis is the amount of experience with a particular environment or task. On the y‐axis is the extent of spatial knowledge acquisition. Because of the lack of vision, blind individuals start at a disadvantage in each of these models. (a) Convergent model: the difference between blind and sighted individuals decreases over time until reaching a similar level of spatial knowledge. (b) Cumulative model: the difference between blind and sighted individuals increases with experience. (c) Persistent model: blind and sighted individuals continue to acquire spatial knowledge with experience, but differences in spatial knowledge remain constant.

Figure 3

A schematic depiction of the neural correlates (i.e., functional and structural) of navigation by the blind. Indicators are organized by study and task. The color of each indicator represents study, and the shape represents type of task. Indicators are placed over the approximate regions corresponding to each study.