Psychosocial responses to outdoor artificial light at night (ALAN): a scoping review

Artificial light at night (ALAN) has sharply increased due to urbanization and expanded nighttime activities. Given its ecological, health, and energy impacts, several countries and cities have begun implementing lighting reductions. Understanding the psychosocial processes and determinants shaping individuals' responses to ALAN is essential for policy acceptance and effectiveness. The objective of this review is to map and synthesize the scientific literature on psychosocial processes and determinants underlying responses to outdoor ALAN, drawing on concepts from environmental psychology.

Following PRISMA-ScR guidelines, 75 (N = 75) studies from seven databases were analyzed to examine psychosocial responses associated with ALAN. Included articles met the following criteria: (1) the article should examine psychosocial responses to outdoor ALAN, such as perceptions, emotions, attitudes, or behaviors, as captured by a wide range of terms used in the literature, (2) present an empirical design, (3) be written in English. This review examines (1) methodological approaches, (2) main psychosocial dimensions, and (3) reported findings.

Four main findings emerged from this review: (1) ALAN research is recent and concentrated in a few countries, (2) studies mainly use quantitative and cross-sectional designs, but varied measures limit comparability, (3) perceptual and emotional responses dominate the literature, while cognitive, motivational, and behavioral dimensions are less studied, and (4) theoretical frameworks, particularly in environmental psychology, are rarely used.

Research on psychosocial responses associated with ALAN is dominated by perceptual and emotional approaches, while key psychosocial processes and determinants (e.g., norms, values, and constraints), central to environmental psychology frameworks, remain underexplored. Future work should adopt environmental psychology models to examine how beliefs, emotions, and routines shape individuals' responses to ALAN and inform acceptable lighting policies.