The contribution of visual attention and declining verbal memory abilities to age-related route learning deficits 2015-2018

DOI

Our ability to learn unfamiliar routes declines in typical and atypical ageing. The reasons for this decline, however, are not well understood. Here we used eye-tracking to investigate how ageing affects people’s ability to attend to navigationally relevant information and to select unique objects as landmarks. We created short routes through a virtual environment, each comprised of four intersections with two objects each, and we systematically manipulated the saliency and uniqueness of these objects. While salient objects might be easier to memorise than non-salient objects, they cannot be used as reliable landmarks if they appear more than once along the route. As cognitive ageing affects executive functions and control of attention, we hypothesised that the process of selecting navigationally relevant objects as landmarks might be affected as well. The behavioural data showed that younger participants outperformed the older participants and the eye-movement data revealed some systematic differences between age groups. Specifically, older adults spent less time looking at the unique, and therefore navigationally relevant, landmark objects. Both young and older participants, however, effectively directed gaze towards the unique and away from the non-unique objects, even if these were more salient. These findings highlight specific age-related differences in the control of attention that could contribute to declining route learning abilities in older age. Interestingly, route-learning performance in the older age group was more variable than in the young age group with some older adults showing performance similar to the young group. These individual differences in route learning performance were strongly associated with verbal and episodic memory abilities.Knowing where we are and how to get to places are fundamental features of successful everyday living. Although most of us rely automatically and unquestioningly on our wayfinding abilities, they are markedly impaired in people with Alzheimer's disease (AD), the most prevalent form of dementia. This project will identify the features of buildings that make them relatively harder or easier for people with AD to navigate. The knowledge gained will allow us to create dementia-friendly architectural guidelines for use in the design of residences for people with AD. Many people with AD eventually move from their familiar home environments into unfamiliar care homes. Unfortunately, the dramatic reduction in wayfinding skills commonly seen at the onset of AD is particularly marked when it comes to learning unfamiliar environments. Thus, people with AD would have an easier transition to new residences if these larger - and often more institutional - environments were designed to be dementia-friendly in terms of wayfinding. A psychological understanding of orientation and navigation could play a major role here but, unfortunately, current design-guidelines are mainly based on custom and practice, not theory and research. This project aims to improve matters through a series of experiments on navigation in people with AD. Our research is innovative in several ways: We will use Virtual Reality (VR) technology to simulate unfamiliar care home environments. VR lets us change environmental features and structures systematically, to monitor how these changes impact on learning to way-find over a period of several weeks. This would be impractical in real world settings. Additionally, by using state-of-the-art eye tracking technology to record gaze direction, we can pinpoint the types of cues people use to find their way through unfamiliar environments (www.spatial-cognition.org). Finally, our experiments will allow us not only to measure the way in which navigation abilities decline in people with AD, but also to identify the mechanisms underlying these declines. Successful navigation depends on learning to recognise places by identifying and remembering landmarks, environmental cues that are unique to each location. We will investigate this process in more detail. Our experiments will examine how AD impacts on landmark selection by comparing the performance of people with AD and healthy adults of a similar age (age-matched controls). Our participants will learn routes through virtual residences that include multiple intersections. We will systematically vary the features present at the intersections to determine whether people with AD have particular difficulties when the same distractor cues are present at more than one intersection, and/or when uninformative cues are nevertheless particularly noticeable (salient). Next, we will use VR to simulate what happens when people move into unfamiliar residences. Over several weeks, we will (a) teach people with AD and age-matched controls to navigate a number of different routes through the same environment, and (b) compare their ability to discover new routes through the same environment, based on knowledge of the routes they have just learned. VR allows for systematic comparisons of different floor plans, so we will be able to establish the kinds of architectural structure that either help or hinder wayfinding in people with AD. A key output of the research will be a set of empirically validated design guidelines that support effective wayfinding in people with AD. Because these principles will be widely applicable, we will work with architects, building standards agencies and care commissioning bodies to ensure that they are used to develop national standards for residential care home design. Our research will thus help to increase or preserve the independence and well-being of people with AD, avoiding a further loss of autonomy, dignity and control that is, in theory, preventable.

A total of 80 participants (32 younger adults [17 females; mean age 24.25 +- 6.38 years; range, 18-40] and 48 older adults [24 females; mean age 73.28 +- 4.82 years; range, 66-82]) took part in the experiment. Participants were first administered a battery of cognitive tests to assess overall cognitive function, verbal and visual memory, and working memory. Thereafter, we tested the participants' route learning performance and measured their eye movements. Participants were shown videos of the routes through the virtual environment in the training phases. In the subsequent test phases, full-screen images of the four intersections were presented in a random order and participants had to indicate the movement direction required to continue along the route by pressing the corresponding arrow key using a standard keyboard.

Identifier
DOI https://doi.org/10.5255/UKDA-SN-853592
Metadata Access https://datacatalogue.cessda.eu/oai-pmh/v0/oai?verb=GetRecord&metadataPrefix=oai_ddi25&identifier=126db7b72f7eb49c65fcd60712d793e83a85cdf3378709f8d3b68432a17b69ad
Provenance
Creator Wiener, J, Bournemouth University; Grzeschik, R, Leibniz Institute for Neurobiology
Publisher UK Data Service
Publication Year 2019
Funding Reference Economic and Social Research Council
Rights Jan Wiener, Bournemouth University. Ramona Grzeschik, Leibniz Institute for Neurobiology; The Data Collection is available to any user without the requirement for registration for download/access.
OpenAccess true
Representation
Resource Type Numeric
Discipline Psychology; Social and Behavioural Sciences
Spatial Coverage Bournemouth; United Kingdom