Spatial navigation is an integral part of many daily life activities, such as visiting friends or relatives and grocery shopping. Every activity that relies on changing locations, even if it is just walking down the street to a neighbor, relies on how well we can navigate. Therefore, a strong link has been found between spatial navigation ability and measures of QOL, autonomy, and mobility.
Numerous studies have looked at spatial navigation among people who have experienced stroke or other forms of acquired brain injury, but data on spatial navigation in patients with MS is highly limited. There are some indications in the literature that visuospatial processing may be affected in MS. Moreover, the contribution of locomotion to quality of spatial navigation may also lead to lower navigation skills.
For a paper published in Multiple Sclerosis and Related Disorders, we aimed to explore spatial navigation impairment in people with MS in a large, representative sample. We included measures of self-reported cognition and locomotion as potential contributors to navigation performance.
Measuring Spatial Navigation Ability
Creating an objective, standardized measure of spatial navigation ability is a difficult task, given the neurocognitive complexity of this cognitive function. To successfully navigate, a good memory of landmarks is necessary, as well as the ability to construct and use mental representations and to process route information. In previous work, we developed an online test battery for spatial navigation ability, the Leiden Navigation Test, that allows us to measure this function in just a few minutes.
Using a video depicting a virtual environment, we assessed knowledge of landmarks and locations and paths between landmarks, to cover all relevant navigation domains. We also included a subjective measure of navigation ability to reflect the perceived navigation performance level of participants. We used our Wayfinding Questionnaire to assess subjective navigation performance, with subscales reflecting Navigation and Orientation, Distance Estimation, and Spatial Anxiety.
A total of 359 people with MS took part in the study and we matched this group with 359 healthy control participants from our existing database from the Leiden Navigation Test, controlling for age, gender, and education level.
Spatial Anxiety Higher Among Patients With MS
Our results indicate that people with MS have substantially lower subjective levels of navigation ability (Table). Earlier findings that MS is linked to lower visuospatial functions is confirmed by a lower ability to memorize landmarks, as established with our objective measures.
Furthermore, higher levels of spatial anxiety were found among patients with MS, meaning that they have greater levels of anxiety when having to find the way by themselves if they walk somewhere alone or when they visit new places. This could certainly impact their well-being when engaging in daily life activities that require active navigation. In other neurological groups, we have often found compensatory behavior in case of severe spatial anxiety, like always bringing a companion when going outdoors or avoiding travel unless necessary. Our additional measures of locomotion and self-reported cognition indicated that selfreported cognition in particular was linked to the occurrence of navigation problems in patients with MS.
Our findings illustrate the need for more knowledge about spatial navigation in MS. Specifically, landmark recognition is lower in this patient population compared with healthy controls, which may hinder the ability to orient oneself or to memorize specific elements of routes. For example, a patient might say: “When I see the old church, I am near the town square.” As this study was set up as a large online study, with limited measurements, a follow-up project with more elaborate cognitive and neuroanatomical measures would be highly informative. That would allow us to connect the particular pattern of navigation performance to other cognitive functions and, possibly, neurological variables in more detail.
