Lateralisation of spatial processing and age

The Road More Travelled: The Differential Effects of Spatial Experience in Young and Elderly Participants

Our spatial mental representations allow us to give refined descriptions of the environment in terms of the relative locations and distances between objects and landmarks. In this study, we investigated the effects of familiarity with the everyday environment, in terms of frequency of exploration and mode of transportation, on categorical and coordinate spatial relations, on young and elderly participants, controlling for socio-demographic factors. Participants were tested with a general anamnesis, a neuropsychological assessment, measures of explorations and the Landmark Positioning on a Map task. The results showed: (a) a modest difference in performance with categorical spatial relations; (b) a larger difference in coordinate spatial relations; (c) a significant moderating effect of age on the relationship between familiarity and spatial relations, with a stronger relation among the elderly than the young. Ceteris paribus, the role of direct experience with exploring their hometown on spatial mental representations appeared to be more important in the elderly than in the young. This advantage appears to make the elderly wiser and likely protects them from the detrimental effects of aging on spatial mental representations.

The impact of age and familiarity with the environment on categorical and coordinate spatial relation representations

Retrieving spatial information is a crucial everyday ability that is affected by age-related changes. Previous research has shown that this change is mediated by familiarity with an environment. The present research uses a series of landmark location tasks to extend and deepen our understanding of the role of aging in spatial mental representations of more or less familiar environments, also disentangling the contribution of coordinate and categorical spatial relations. The study tested the following hypotheses: (1) younger adults only have an advantage over the elderly in less familiar environments; (2) the advantage for categorical over coordinate spatial relations is mainly found for less familiar environments; and finally; (3) interactions between age, familiarity, and spatial relations might reveal that the effects of age and familiarity take different trajectories for coordinate and categorical spatial relations. Results confirmed that: (1) young people outperform the elderly only in less familiar environments; (2) there is a reduction in the difference between coordinate and categorical accuracy with increasing familiarity with the environment; while (3) the interaction between age and level of familiarity did not significantly differentiate coordinate from categorical spatial relations. In conclusion, the present study provides new evidence for the role of familiarity with geographical areas and its impact on the representation of categorical and coordinate relations, with practical implications for the assessment of topographical disorientation in aging.

Studying Individual Differences in Spatial Cognition Through Differential Item Functioning Analysis

Background: In the field of spatial cognition, the study of individual differences represents a typical research topic. Gender and age have been prominently investigated. A promising statistical technique used to identify the different responses to items in relation to different group memberships is the Differential Item Functioning Analysis (DIF). The aim of the present study was to investigate the DIF of the Landmark positioning on a Map (LPM) task, across age groups (young and elderly) and gender, in a sample of 400 healthy human participants. Methods: LPM is a hometown map completion test based on well-known and familiar landmarks used to assess allocentric mental representations. DIF was assessed on LPM items two times: on categorical (i.e., positions) and coordinate (i.e., distances) scores, separately. Results: When positions and distances were difficult to assess with respect to the intended reference point, the probability to endorse the items seemed to get worse for the elderly compared to the younger participants. Instead other features of landmarks (high pleasantness, restorativeness) seemed to improve the elderly performance. A gender-related improvement of probability to endorse distance estimation of some landmarks, favoring women, emerged, probably associated with their repeated experiences with those landmarks. Overall, the complexity of the task seemed to have a differential impact on young and elderly people while gender-oriented activities and places seemed to have a differential impact on men and women. Conclusions: For the first time DIF was applied to a spatial mental representation task, based on the schematic sketch maps of the participants. The application of DIF to the study of individual differences in spatial cognition should become a systematic routine to early detect differential items, improving knowledge, as well as experimental control, on individual differences.

Age-Related Deficits in Visuospatial Memory Are due to Changes in Preparatory Set and Eye-Hand Coordination

OBJECTIVES

Healthy aging is associated with a decline in visuospatial working memory. The nature of the changes leading to this decline in response of the eye and/or hand is still under debate. This study aims to establish whether impairments observed in performance on cognitive tasks are due to actual cognitive effects or are caused by motor-related eye-hand coordination.

METHODS

We implemented a computerized version of the Corsi span task. The eye and touch responses of healthy young and older adults were recorded to a series of remembered targets on a screen.

RESULTS

Results revealed differences in fixation strategies between the young and the old with increasing cognitive demand, which resulted in higher error rates in the older group. We observed increasing reaction times and durations between fixations and touches to targets, with increasing memory load and delays in both the eye and the hand in the older adults.

DISCUSSION

Our results show that older adults have difficulty maintaining a "preparatory set" for durations longer than 5 s and with increases in memory load. Attentional differences cannot account for our results, and differences in age groups appear to be principally memory related. Older adults reveal poorer eye-hand coordination, which is further confounded by increasing delay and complexity.

Spatial judgments in patients with retinitis pigmentosa

Previous investigations into cortical plasticity in the presence of ocular disease have focused on central retinal damage. Perceptually, patients often report distortions of visual space which can be partially explained by perceptual filling-in. The mechanisms involved could also apply to peripheral field loss. Spatial interval discrimination was tested in 28 retinitis pigmentosa (RP) patients and a control group. When stimuli were presented to both hemispheres, bias did not differ whereas threshold was poorer in RP patients. When presenting the task to only one hemifield, bias was related to field asymmetry, but only in the left visual field, r(2)=.59. Brain laterality may be an important factor when examining changes in cortical function in response to peripheral system damage.