Route repetition and route retracing: effects of cognitive aging

Retracing a recently traveled route is a frequent navigation task when learning novel routes or exploring unfamiliar environments. In the present study we utilized virtual environments technology to investigate age-related differences in repeating and retracing a learned route. In the training phase of the experiment participants were guided along a route consisting of multiple intersections each featuring one unique landmark. In the subsequent test phase, they were guided along short sections of the route and asked to indicate overall travel direction (repetition or retracing), the direction required to continue along the route, and the next landmark they would encounter. Results demonstrate age-related deficits in all three tasks. More specifically, in contrast to younger participants, the older participants had greater problems during route retracing than during route repetition. While route repetition can be solved with egocentric response or route strategies, successfully retracing a route requires allocentric processing. The age-related deficits in route retracing are discussed in the context of impaired allocentric processing and shift from allocentric to egocentric navigation strategies as a consequence of age-related hippocampal degeneration. - See more at: http://journal.frontiersin.org/Journal/10.3389/fnagi.2012.00007/abstract#sthash.xK4Htsfy.dpu

Maladaptive bias for extrahippocampal navigation strategies in aging humans.

Efficient spatial navigation requires not only accurate spatial knowledge but also the selection of appropriate strategies. Using a novel paradigm that allowed us to distinguish between beacon, associative cue, and place strategies, we investigated the effects of cognitive aging on the selection and adoption of navigation strategies in humans. Participants were required to rejoin a previously learned route encountered from an unfamiliar direction. Successful performance required the use of an allocentric place strategy, which was increasingly observed in young participants over six experimental sessions. In contrast, older participants, who were able to recall the route when approaching intersections from the same direction as during encoding, failed to use the correct place strategy when approaching intersections from novel directions. Instead, they continuously used a beacon strategy and showed no evidence of changing their behavior across the six sessions. Given that this bias was already apparent in the first experimental session, the inability to adopt the correct place strategy is not related to an inability to switch from a firmly established response strategy to an allocentric place strategy. Rather, and in line with previous research, age-related deficits in allocentric processing result in shifts in preferred navigation strategies and an overall bias for response strategies. The specific preference for a beacon strategy is discussed in the context of a possible dissociation between beacon-based and associative-cue-based response learning in the striatum, with the latter being more sensitive to age-related changes

Gaze Behaviour during Space Perception and Spatial Decision Making

A series of four experiments investigating gaze behavior and decision making in the context of wayfinding is reported. Participants were presented with screen-shots of choice points taken in large virtual environments. Each screen-shot depicted alternative path options. In Experiment 1, participants had to decide between them in order to find an object hidden in the environment. In Experiment 2, participants were first informed about which path option to take as if following a guided route. Subsequently they were presented with the same images in random order and had to indicate which path option they chose during initial exposure. In Experiment 1, we demonstrate (1) that participants have a tendency to choose the path option that featured the longer line of sight, and (2) a robust gaze bias towards the eventually chosen path option. In Experiment 2, systematic differences in gaze behavior towards the alternative path options between encoding and decoding were observed. Based on data from Experiments 1 & 2 and two control experiments ensuring that fixation patterns were specific to the spatial tasks, we develop a tentative model of gaze behavior during wayfinding decision making suggesting that particular attention was paid to image areas depicting changes in the local geometry of the environments such as corners, openings, and occlusions. Together, the results suggest that gaze during a wayfinding tasks is directed toward, and can be predicted by, a subset of environmental features and that gaze bias effects are a general phenomenon of visual decision making

(Dis)orientation and Design Preferences Within an Unfamiliar Care Environment: A Content Analysis of Older Adults’ Qualitative Reports After Route Learning

© The Author(s) 2020. Ensuring that environments are designed to cater for those with decreasing orientation, perceptual and mobility skills, is an example of how environments are being changed to become more age and dementia friendly. However, environmental design should directly involve potential users of the environment to ensure that their views are accounted for. Four open-ended questions, focusing on orientation strategies, reasons for disorientation, and design preferences, were given to 32 older adults after they had completed a route learning task through an unfamiliar environment. A Content Analysis found a strong focus on participants’ ability to memorize routes based on verbally encoding the route and on their ability to remember landmarks, with the reports linking closely to cognitive theories of navigation. Design suggestions included the importance of a homely and welcoming environment, memorable features, and access to the outdoors. The findings can be used inform age and dementia friendly design principles

Impairment in active navigation from trauma and Post-Traumatic Stress Disorder.

The study investigated the impact of trauma exposure and of Post-Traumatic Stress Disorder (PTSD) on spatial processing and active navigation in a sample (n = 138) comprising civilians (n = 91), police officers (n = 22) and veterans (n = 27). Individuals with previous trauma exposure exhibited significantly poorer hippocampal-dependent (allocentric) navigation performance on active navigation in a virtual environment (the Alternative Route task) regardless of whether or not they had PTSD (scoring above 20 on the PTSD Diagnostic Scale). No performance differences were found in static perspective taking (the Four Mountains task). Moreover, an associative information processing bias in those with PTSD interfered with ability to use hippocampal-dependent processing in active navigation. This study provides new evidence of impaired active navigation in individuals with trauma exposure and highlights the importance of considering the relationship between trauma and spatial processing in clinical and occupational settings

Age-related differences in visual encoding and response strategies contribute to spatial memory deficits.

Successful navigation requires memorising and recognising the locations of objects across different perspectives. Although these abilities rely on hippocampal functioning, which is susceptible to degeneration in older adults, little is known about the effects of ageing on encoding and response strategies that are used to recognise spatial configurations. To investigate this, we asked young and older participants to encode the locations of objects in a virtual room shown as a picture on a computer screen. Participants were then shown a second picture of the same room taken from the same (0°) or a different perspective (45° or 135°) and had to judge whether the objects occupied the same or different locations. Overall, older adults had greater difficulty with the task than younger adults although the introduction of a perspective shift between encoding and testing impaired performance in both age groups. Diffusion modelling revealed that older adults adopted a more conservative response strategy, while the analysis of gaze patterns showed an age-related shift in visual-encoding strategies with older adults attending to more information when memorising the positions of objects in space. Overall, results suggest that ageing is associated with declines in spatial processing abilities, with older individuals shifting towards a more conservative decision style and relying more on encoding target object positions using room-based cues compared to younger adults, who focus more on encoding the spatial relationships among object clusters

Ageing- and dementia-friendly design: theory and evidence from cognitive psychology, neuropsychology and environmental psychology can contribute to design guidelines that minimise spatial disorientation.

Many older people, both with and without dementia, eventually move from their familiar home environments into unfamiliar surroundings, such as sheltered housing or care homes. Age-related declines in wayfinding skills can make it difficult to learn to navigate in these new, unfamiliar environments. To facilitate the transition to their new accommodation, it is therefore important to develop retirement complexes and care homes specifically designed to reduce the wayfinding difficulties of older people and those with Alzheimer's disease (AD). Residential complexes that are designed to support spatial orientation and that compensate for impaired navigation abilities would make it easier for people with dementia to adapt to their new living environment. This would improve the independence, quality of life and well-being of residents, and reduce the caregivers' workload. Based on these premises, this opinion paper considers how evidence from cognitive psychology, neuropsychology and environmental psychology can contribute to ageing- and dementia-friendly design with a view to minimising spatial disorientation. After an introduction of the cognitive mechanisms and processes involved in spatial navigation, and the changes that occur in typical and atypical ageing, research from the field of environmental psychology is considered, highlighting design factors likely to facilitate (or impair) indoor wayfinding in complex buildings. Finally, psychological theories and design knowledge are combined to suggest ageing- and dementia-friendly design guidelines that aim to minimise spatial disorientation by focusing on residual navigation skills

The Aging Navigational System

The discovery of neuronal systems dedicated to computing spatial information, composed of functionally distinct cell types such as place and grid cells, combined with an extensive body of human-based behavioral and neuroimaging research has provided us with a detailed understanding of the brain's navigation circuit. In this review, we discuss emerging evidence from rodents, non-human primates, and humans that demonstrates how cognitive aging affects the navigational computations supported by these systems. Critically, we show 1) that navigational deficits cannot solely be explained by general deficits in learning and memory, 2) that there is no uniform decline across different navigational computations, and 3) that navigational deficits might be sensitive markers for impending pathological decline. Following an introduction to the mechanisms underlying spatial navigation and how they relate to general processes of learning and memory, the review discusses how aging affects the perception and integration of spatial information, the creation and storage of memory traces for spatial information, and the use of spatial information during navigational behavior. The closing section highlights the clinical potential of behavioral and neural markers of spatial navigation, with a particular emphasis on neurodegenerative disorders

Evidence for age-related deficits in object-location binding during place recognition.

Deciding whether a place is the same or different than places encountered previously is a common task in daily navigation which requires to develop knowledge about the locations of objects (object-location binding) and to recognize places from different perspectives. These abilities rely on hippocampal functioning which is susceptible to increasing age. Thus, the question of the present study is how they both together impact on place recognition in aging. Forty people aged 20-29, 44 aged 60-69, and 32 aged 70-79 were presented with places consisting of four different objects during the encoding phase. In the test phase, they were then presented with a second place and had to decide whether it was the same or different. Test places were presented from different perspectives (0°, 30°, 60°) and with different object conditions (same, a swap of two objects, a substitution with a novel object). The sensitivity for detecting changes (d') decreased from 20-29 to 60-69 and to 70-79 years old, and with increasing perspective shifts. Importantly, older adults were less sensitive to object swapping than to object substitution, while young participants did not show any difference. Overall, these results suggest specific age-related difficulties in object-location binding in the context of place recognition