−43%
adding indoor plants nearly halved students' simple reaction times
Exact: from 527.9 ms to 301.4 ms
Simple reaction time improved from 527.9 ms to 301.4 ms with indoor plants
In the post-renovation classroom, students' average simple response time (SRT) was 527.9 milliseconds without plants and 301.4 milliseconds with plants present. This substantial improvement suggests that biophilic elements such as indoor plants enhance cognitive performance and concentration beyond the gains achieved by thermal renovation alone.
the average response time for simple tasks decreasing from 527.9 milliseconds to 301.4 milliseconds and for choice tasks, from 589.5 milliseconds to 439.1 milliseconds.
Related findings
90%
people in modern societies spend nine-tenths of their time indoors in built environments
Modern humans spend about 90% of their time indoors
Tonia Gray et al., 2014, International Journal of Environmental Research and Public Health
82.0%
high perceived impact of environmental design on children's behavioral and academic outcomes
Inclusive architectural design is perceived to strongly support behavioral and academic outcomes for children with neurodevelopmental disorders
Heba M. Abdou et al., 2026, Architecture
90%
people spend most of their lives indoors
People spend nearly 90% of their time indoors
Hessa Humaid Aljarwan Alshamsi et al., 2026, Indoor and Built Environment
Read more in
Education What school spaces do to children
Where the evidence on classroom air, acoustics, light and green is robust, where it is thin, and what to measure before the build.
Healthcare 
Workplace What your office costs
Four design variables that move cognitive performance and who pays for them
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