Place learning in aging women.

Abstract

Place learning, a function of the hippocampus (HPC) in the brain, is the ability to make mental maps of environments; it is a critical cognitive function needed to learn new or changed environments. Place learning is often impaired with aging, possibly due to changes in HPC function. Due to factors such as hospitalization and relocation, elders frequently must learn new places. Environmental conditions that influence elders' ability to learn new or changed environments are not known. It was hypothesized that salient (prominent and meaningful) and stable cues (unchanging) would be particularly important for place learning in elders as compared to young women. Socialization in the form of larger social networks, and increased exposure to new and varied environments (life space mobility) were also hypothesized to improve place learning performance. Twenty healthy older (over 65) and 6 younger (18--35) women were recruited from senior centers, churches, and independent senior living centers. Pre-tests for visual acuity, cognition (MMSE), verbal and spatial working memory were conducted. Place learning was measured by the Computer Generated (CG) Arena, a virtual reality task, which required subjects to use constellations of environmental cues to find a hidden platform in four different environments, which varied with respect to stability and salience of cues. Subjects received 6 learning trials in each environment. Place learning was measured as time to target, directional heading error, time spent in the target quadrant, and path length to target. Linear mixed model analysis revealed a significant effect of age (F = 4.083, p = .044), cue properties (F = 6.880, p ≤ .0001), trial (F = 6.394, p = .012), attentional capacity (F = 2.843, p ≤ .037), social networks (F = 4.550, p ≤ .033) and life space mobility (F = 8.233, p = .004) on place learning measures. Subjects learned the best under highly salient and stable cue conditions. In contrast to young, older women did not learn in nonsalient or unstable cue conditions. These data support the hypothesis that older women can learn new places, but learning is slow and depends on high degrees of salience and stability in the environmental surround. This study adds to the understanding of nursing considerations for environmental modifications to promote independence for older individuals.