Perceptual learning improves spatial contrast sensitivity in older adults

Yong Tang¹Ju Liang²Yifeng Zhou^3*

• ¹Anhui Institute of Medicine, Hefei, China
• ²Sichuan Fine Arts Institute, Chongqing, China
• ³Hefei National Laboratory for Physical Science at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China

Abstract Widespread visual deficits accompany normal aging, and most of these deficits are attributed to a functional degradation of the visual cortex. However, many visual functions in older adults can be improved through perceptual learning, suggesting a potential approach to counteract age-related declines. Yet, it remains unclear whether perceptual learning can improve the spatial contrast sensitivity, a fundamental visual function known to decline significantly from around age forty, in older adults. To address this question, we trained 29 older adults and 18 young controls using contrast perceptual learning at seven spatial frequencies, ranging from low to high, and/or at the cut-off spatial frequency. Spatial contrast sensitivity function and visual acuity were measured before and after training. We found that training could induce substantial improvements in spatial contrast sensitivity function and visual acuity of older adults, which could be retained at least several months. Additionally, analyses of transfer effects of perceptual learning revealed that, compared to young controls, older adults exhibited a characteristic low-frequency shift in peak improvement and a slightly broader bandwidth, which might be associated with age-related alterations in neuronal response properties within the primary visual cortex. These findings indicated a substantial neural plasticity in the aging visual system, and support the potential of perceptual learning as a clinically viable intervention for mitigating age-related visual decline.