An Arousal Optimization Model of Lighting Level Preferences: An Interaction of Social Situation and Task Demands

Both the lighting level of a setting and the social situation can affect arousal. If individuals attempt to maintain an optimal arousal level, then preferred lighting levels for a particular setting should vary with social variables. The purpose of this study was to examine this hypothesis. Male and female subjects (N = 105) were presented with 48 hypothetical situations and were asked to indicate their lighting level preferences for each. Some of the situations involved activities requiring a high degree of visual attention, while the other situations involved activities of a nonvisual nature. Activities were crossed with a social variable: a platonic friend present, a romantic partner present, or a group of platonic friends present. Across all activities, brightness preferences for the romantic partner situations were significantly lower than preferences for either the platonic friend situations or the group of friends situations. The effect of the social situation was very strong for nonvisual activities, but it was considerably weakened for visual activities. Also, brightness preferences were lower for situations with a group of friends than with one friend, but only for complex tasks. The results are consistent with arousal optimization theory.