A study on the impact of Visible Green Index and vegetation structures on brain wave change in residential landscape

Visible Green Index (VGI) reflects the degree of greening from human vision to affect human health and well-being that has gradually become a new type of urban green space index. But few studies show how human re-acts to VGI under different vegetation structures. This study designed and conducted an experiment to evaluate human's response to scenes which were panoramic pictures of residential green spaces and projected by Virtual Reality. Participants (n = 97) were asked to do deep breath training and then they immersed in the VR experience of three groups scenes with different VGI and vegetation structure for five minutes, during which we collected Electroencephalography data, which indicated that the most suitable scene for human brain is a VGI of 60% to 80% with a three-layer vegetation structure by multiple comparisons. But the two-layer vegetation structure with a VGI above 80% can have the greatest instantaneous weakening effect. Besides, residential landscape is most significant in reducing brain waves of delta and theta, and we propose that a VGI of 60% can be used as a VGI grading indicator. The study provides a certain theoretical basis for the landscape planning of residential areas, which is helpful to improve the theory of VGI and promote its establishment as a new type of urban green spaces indicator. Our findings also further verify the relationship between landscape and human health.

Automated summary

Through a virtual reality experiment, the study found that a VGI of 60% to 80% with a three-layer vegetation structure is most beneficial for the human brain, while a two-layer vegetation structure with a VGI above 80% has the greatest instantaneous weakening effect. Additionally, residential landscapes significantly reduce delta and theta brain waves in humans.