Ma and colleagues evaluated the repercussions of viewing indoor green walls. They found a link between looking at green walls of certain sizes and mental state: “Subjects’ cognitive performance was highly improved in the presence of a large green wall [green view index (GVI) = 15%]. Systolic blood pressure and heart rate were reduced . . . most significantly in the presence of a large green wall. Diastolic blood pressure decreased significantly . . . in the presence of a small green wall [GVI = 5%].” GVI is defined as “the percentage of green area within the human line of sight.” Also, when the larger green walls were in place temperatures felt more comfortable.
Xiaoyan Ma, Meng Du, Pei Deng, Tianhong Zhou, and Bo Hong. “Effects of Green Walls on Thermal Perception and Cognitive Performance: An Indoor Study.” Building and Environment, in press, https://doi.org/10.1016/j.buildenv.2024.111180