Alzheimer’s disease and related dementias is the collective term for a progressive neurodegenerative disease for which there is presently no cure. This paper focuses on two symptoms of the disease, sleep disturbances and depression, and discusses how light can be used as a non-pharmacological intervention to mitigate their negative effects. Bright days and dark nights are needed for health and well-being, but the present components of the built environment, especially those places where older adults spend most of their days, are too dimly illuminated during the day and too bright at night. To be effective light needs to be correctly specified, implemented and measured. Yet, without the appropriate specification and measurement of the stimulus, researchers will not be able to successfully demonstrate positive results in the field, nor will lighting designers and specifiers have the confidence to implement lighting solutions for promoting better sleep and mood in this population.

阿尔茨海默病和相关痴呆症是目前无法治愈的进行性神经退行性疾病的统称。本文重点介绍该疾病的两个症状，睡眠障碍和抑郁症，并讨论如何将光用作非药物干预来减轻其负面影响。健康和幸福需要白天和黑夜，但建筑环境的现有组成部分，尤其是老年人度过大部分时间的地方，白天照明太暗，晚上太亮。要想成为有效的光，需要正确地指定、实施和测量。然而，如果没有对刺激进行适当的规范和测量，研究人员将无法在该领域成功展示积极的结果，