In 1986 Judith Heerwagen and Gordon Orians walked through 75 offices on the University of Washington campus and counted what hung on the walls. The windowless offices carried 195 pieces of visual material, the windowed ones 82. The content differed as well. People without a window put up landscapes, people with one put up cityscapes, and the nature themes clustered in the rooms that had no outside to look at.
The substitutes have since become electronic. In 2025 Shuhan Liu compared a real window, an artificial window and no window at all, with heart rate variability recorded alongside cognitive tests. Against the windowless condition the artificial window raised the nLF/nHF focus ratio by about 22.2 per cent and cut attention test times by 14.4 per cent. On lighting comfort and acceptability it beat the real window.
Fariba Mostajeran built the same question in virtual reality in 2023. Thirty-nine people worked in a virtual office with plants and in one without, and scored higher on short-term memory and creativity with the plants there. Asked afterwards which office they preferred, 32 of the 39 chose the planted one and none chose the empty one. Mostajeran also passes on two of the most-quoted figures in this literature, Lohr’s 12 per cent and Nieuwenhuis’s 15 per cent. Neither original is open to us.
The most isolated test of the idea ran at the South Pole. Stijn Thoolen put 25 overwintering crew members through 16 variations of sensory stimulation at the end of their mission in 2025, varying delivery, content, duration and temperature cues. State anxiety fell by 1.7 points after nature scenes and rose by 1.0 after city scenes on a scale running from 20 to 80, with t = 4.805 and p below 0.001. Preferences beyond that split by person rather than by rule.
Michael Varkovetski’s 12 per cent, the difference between 54.33 seconds and 62.04 on an attention task, was published in an undergraduate research journal. And Nathalie Gerner’s feasibility study in 2025 found no significant interaction at all between cognitive state and nature-inspired design across five established EEG ratios, working with 20 people and consumer-grade equipment whose limits Gerner names.