Blue Matters: Using EEG Technology to Measure Impacts of Various Bluescapes on Human’s Psycho-Physiological Restoration

Abstract

Water is an essential ecological and landscape element. Bluescape in this study refers to all visible, outdoor, naturalistic environments that prominently feature surface water, including rivers, canals, lakes, streams, ponds, and wetlands. We exclude outdoor swimming pools and fountains. A growing body of literature suggests that bluescapes are potentially beneficial to human health and well-being. While current studies mostly use coarse categories of bluescapes and focus on the method and frequency of exposure, we do not know whether and to what extent landscape type and exposure duration impact the restoration effects of bluescapes. This study examined peoples’ psycho-physiological responses (N=30) to diverse types of bluescapes. We selected three common types of bluescapes found in inland natural open spaces: Falling bluescapes (e.g., waterfalls), Flowing bluescapes (e.g., rivers, streams, and canals); and Static bluescapes (e.g., lakes, basins and ponds). We also included a completely human-made, unnatural urban street setting (Cityscape). Participants experienced four conditions, Falling, Flowing, Static bluescape, and Cityscape (control), by viewing a four-minute slideshow for each landscape, consisting of a one-minute white blank slide (baseline) and three-minute landscape images, in random order. We applied portable Electroencephalograms technology to record participants’ brainwaves continuously as they viewed the slides and adopted the Restorative Components Scale to measure restoration potential. Alpha and beta waves are strongly relevant to the present study. Increased alpha waves are associated with calmness, relaxation and a meditate state. Lower beta is associated with recovery from stress and mental fatigue. There are three main findings in this within-subject experimental study. First, results show that all three bluescape conditions evoked significantly physiological restoration compared to cityscapes. We argue that visual exposure to bluescapes does offer significant psycho-physiological restoration compared to the cityscape. Second, results show that different bluescapes elicit significantly different psycho-physiological resotrativeness, with the Falling eliciting the highest restorative effects. We suggest that the restorative effects are different among different types of bluescapes, and the Falling was the most restorative. Third, results show that landscape type produced significant effects on α1, α2, and β2 waves, exposure time was only significant for β1 waves. So we suggest that the differences between restorative benefits among the four landscapes might mainly resulted from differences in landscape type, and less from exposure time. These results can offer guidance for designers and citizens in terms of bluescape types and exposure duration to achieve optimal restoration effects.