Upstate, Harvard, Syracuse study shows how better indoor environments enhance cognitive function
“The Impact of Green Buildings on Cognitive Function” study found that employees’ cognitive performance scores averaged 101 percent higher in green building environments with enhanced ventilation compared to a conventional building environment.
“When it comes to the decision-making ability of green building occupants, intelligence is in the air,” said John Mandyck, chief sustainability officer for United Technologies. “We know green buildings conserve natural resources, minimize environmental impacts and improve the indoor environment, but these results show they can also become important human resource tools for all indoor environments where cognitive abilities are critical to productivity, learning and safety. Given that, once built, more than 90 percent of the costs associated with a building are related to the people who work within it, the payback for improved indoor environmental quality far outweighs the investment.”
Led by public health professionals, the double-blind study evaluated the cognitive performance of 24 participants exposed to conditions in a laboratory setting that simulate those found in conventional and green buildings, as well as green buildings with enhanced ventilation. Researchers measured cognitive function for nine functional domains including basic, applied and focused activity levels; task orientation; crisis response; information seeking; information usage; breadth of approach; and strategy.
The largest improvements in cognitive function occurred with crisis response, information usage and strategy.
- Crisis response scores were 97 percent higher for the green environment and 131 percent higher for the enhanced green environment compared to the conventional environment.
- Information usage scores for green and enhanced green environments were 172 and 299 percent higher than in the conventional environment, respectively.
- For strategy, green and enhanced green scores were 183 and 288 percent higher than the conventional environment.
“This study demonstrates that indoor environments can have a profound impact on the decision-making performance of workers, which is a primary indicator of worker productivity,” said Dr. Joseph Allen, assistant professor of exposure assessment science at the Harvard T.H. Chan School of Public Health, and principal investigator for the study. “These results are powerful for three reasons. First, they suggest that the levels of carbon dioxide and volatile organic compounds that we commonly encounter in conventional office buildings are associated with decreases in worker performance compared to when those same workers are in green building environments. Second, when we enhance ventilation and optimize indoor environmental conditions, we see improvements in the cognitive function of workers. And third, these results fill important knowledge gaps in existing research about the relationship between green buildings and occupant health.”
The study was conducted in the environmentally controlled Total Indoor Environmental Quality Laboratory at the Syracuse Center of Excellence in Environmental and Energy Systems in Syracuse, and took place over the course of six workdays spread across a two-week period.
“Participants spent each day during the test period conducting their normal work activities in indoor environments that are encountered every day by large numbers of workers,” said Dr. Suresh Santanam, associate professor of biomedical and chemical engineering at Syracuse University and study co-investigator. “Because of the controlled way in which the study was designed and conducted within the state-of-the-art lab, we’re confident of the results, which are very significant.”
At the end of each six-hour workday, participants completed a 1.5 hour cognitive assessment using a well-validated, computer-based cognitive assessment. “The Strategic Management Simulation evaluates decision making and has been used by more than 70,000 participants worldwide over the last seven decades,” said study co-investigator Dr. Usha Satish, professor of psychiatry and behavioral sciences at Upstate Medical University. “It gives participants the freedom to make decisions based on their own cognitive styles and is reflective of their performance in the real world. The gains in performance output under conditions of improved indoor environments could be seen in areas such as the handling of day-to-day workplace challenges, where they were better able to understand and use their resources with optimal task prioritization.”
Due to the study’s groundbreaking findings, Harvard and Upstate with the support of United Technologies are launching a second phase of research, which will move from the lab into real buildings across the United States.
Caption: Study investigators are, from left, Joseph Allen, Harvard University; Suresh Santanam, Syracuse University; Usha Satish, SUNY Upstate Medical University; and project manager Piers MacNaughton, Harvard University.