Perceptions of lighting, perceived restorativeness, preference and fear in outdoor spaces

This thesis considers outdoor lighting as a fundamental factor affecting environmental experiences after dark. It explores the restorative potential of outdoor lighting within the framework provided by attention restoration theory (ART). Also, perceived safety and preference variables are included in the research work. These factors may have a major effect on outdoor space use after dark and on the level of satisfaction with the neighbourhood in which a person lives. The modern way of living calls for a capacity for long and intense periods of concentration, the ability to direct attention. However, this mental effort is susceptible to fatigue and a restorative period is needed before a person can be effective again. Thus, the need for restoration may be considerable during the evening, and public lighting environments should promote opportunities for restoration. This thesis explores how the perception of different lighting attributes is connected with the perception of restorative potential. The research method was based on subjective assessments of simulated environments as well as field assessments. The results were obtained by applying quantitative analysis methods to the assessment data. In studies III and IV, the quantitative data was supplemented with qualitative data obtained from free responses. Both hypothesis testing with ANOVA and linear regression were used for quantitative data analysis. The main finding is that the perceived quality of the lighting environment correlates with perceptions about the potential for restoration, thus providing a new framework for lighting research. The results indicate that perceived restorativeness is positively connected with the perception of such lighting attributes as the focus of light on natural scene contents and the perception of a pleasant colour quality, whereas the connection may be negative when the light is focused on urban scene contents. The results also indicate that perceptions of safe and a pleasant lighting environment are connected with the perception of a pleasant colour quality. Also, changes in the focus of the lighting affected preferences and feelings of safety, so that when the light was focused on natural scene contents, the preferences and perceptions of safety were higher, whereas they were lower when the light was focused on parking lots and roads. Thus, the results suggest putting more weight on the quality of lighting.