Effects of spatio-temporal features of Komorebi dappled light on human responses

Komorebi, the dappled sunlight filtering through trees, has shown restorative potential in both outdoor and indoor settings, yet which specific properties of these dynamic light patterns drive human responses remains unclear. This study examined how six spatio-temporal features of Komorebi, characterising brightness dynamics, movement patterns, and light patch organisation, relate to subjective and physiological responses. In a controlled experiment, 115 participants viewed eight Komorebi video projections and a static Venetian blind baseline while subjective ratings and physiological measures were recorded, followed by interviews at the end of the experiment. Quantitative analysis revealed that brightness tempo (!) and spatial brightness heterogeneity (Moran’s I I I) were each associated with both subjective and physiological outcomes, while patch dispersion (NNI) and direction consistency (D ∀) showed broad associations across subjective measures. Slower brightness fluctuations, heterogeneous brightness distributions, clustered patches, and varied movement directions each enhanced distinct aspects of the Komorebi experience, from calmness and pleasantness to parasympathetic cardiac activity. Interview data provided additional support for these quantitative patterns. These findings provide a useful set of parameters for translating the restorative qualities of natural dappled light into indoor biophilic lighting applications.